Diaphragm, Sound Generating Device, and Electronic Device

Abstract

The present invention discloses a diaphragm, a sound generating device and an electronic device. The diaphragm includes a main body portion and a conductive portion. Among them, the main body portion includes a rubber material layer, the conductive portion is disposed on the rubber material layer and at least a part of the conductive portion is exposed from the main body portion to be electrically connected to the voice coil and an external circuit. The conductive portion includes a matrix and conductive particles dispersed in the matrix, and the matrix is composed of a heterochain polymer with a -NH-COO- characteristic group. In the matrix of the conductive portion of the diaphragm of the present invention, there is a heterochain polymer with a -NH-COO- characteristic group, which not only enables the conductive portion to have good adhesion to the main body portion, but also can enhance the bonding force between the matrix and the conductive particles, ensuring the consistency of the diaphragm during the stretching process, thereby achieving good resilience of the diaphragm and ensuring the sound quality stability of the diaphragm during long-term use.

Description

Technical Field

[0001] The present invention relates to the field of electro-acoustic technologies, and more specifically, to a diaphragm of a sound generating device, a sound generating device using the diaphragm, and an electronic device using the sound generating device. Background Art

[0002] A sound generating device generally includes a diaphragm, a voice coil combined on one side of the diaphragm, and an electrical connector for electrically connecting an internal circuit and an external circuit of the sound generating device. Among them, the voice coil includes two voice coil leads, and the two voice coil leads are electrically connected to two pads of the electrical connector by spot welding or the like. The electrical connector is simultaneously electrically connected to the external circuit to control the electrical signal in the voice coil through the electrical signal of the terminal product. Generally speaking, the leads of the voice coil need to extend a certain length of wire, and are suspended to achieve electrical connection with the electrical connector. Although the suspended lead structure can achieve high sensitivity, due to the limitation of the suspended leads, the amplitude of the voice coil cannot be too large, and the risk of wire breakage is relatively high, and the low-frequency effect is not significant enough to provide a better auditory experience for users.

[0003] In existing products, some sound generating devices also include a centering washer. The centering washer is usually combined on one side of the diaphragm, and the centering washer can be used as an electrical connector between the voice coil and the outside. Specifically, the leads of the voice coil are connected to the centering washer, and the centering washer is connected to the external circuit to achieve electrical connection. In fact, although the application of the centering washer effectively solves the hidden danger of wire breakage of the voice coil leads, the presence of the centering washer will occupy the internal space of the sound generating device, thereby losing the acoustic performance of the product to a certain extent, and further reducing the audio experience of users. Moreover, since the centering washer needs to be connected to the diaphragm / voice coil, the vibration consistency of the vibration system is affected, and large-amplitude vibration cannot be achieved. In addition, the centering washer has a relatively high hardness compared to the diaphragm material, thereby affecting the resilience of the diaphragm. Summary of the Invention

[0004] An object of the present invention is to provide a diaphragm having the advantages of high resilience and good vibration consistency.

[0005] Another object of the present invention is to provide a sound generating device composed of the above diaphragm.

[0006] Still another object of the present invention is to provide an electronic device composed of the above sound generating device.

[0007] In order to achieve the above objects, the present invention provides the following technical solutions.

[0008] The diaphragm according to an embodiment of the first aspect of the present invention includes a main body portion and a conductive portion. Among them, the main body portion includes a rubber material layer, the conductive portion is disposed on the rubber material layer and at least a part of the conductive portion is exposed outside the main body portion to be electrically connected to a voice coil and an external circuit. The conductive portion includes a matrix and conductive particles dispersed in the matrix, and the matrix is composed of a heterochain polymer with a -NH-COO- characteristic group.

[0009] For the diaphragm according to an embodiment of the first aspect of the present invention, the combination of the main body portion and the conductive portion is adopted for the diaphragm, which not only realizes the electrical connection between the voice coil and the external circuit, but also avoids the problems of loss of internal space caused by connecting components such as centering washers and easy breakage of leads. In addition, the matrix of the conductive portion contains a heterochain polymer with a -NH-COO- characteristic group, and the main body portion adopts a rubber material, which not only enables the conductive portion to have good adhesion to the main body portion, but also can enhance the bonding force between the matrix and the conductive particles, ensuring the consistency of the diaphragm during the stretching process, thereby realizing good resilience of the diaphragm and ensuring the sound quality stability of the diaphragm during long-term use. This diaphragm is suitable for sound generating devices with requirements of large displacement and high resilience (such as high loudness, deep waterproofing, etc.).

[0010] According to some embodiments of the present invention, the thickness of the diaphragm is 30μm to 200μm, and the thickness of the conductive portion is 0.5μm to 50μm.

[0011] According to some embodiments of the present invention, a part of the main body portion opposite to the conductive portion and the conductive portion together form a composite portion. When the composite portion has a tensile strain of 20%, there is no delamination between the conductive portion and the main body portion, and the elastic recovery rate of the composite portion is greater than 70%.

[0012] According to some embodiments of the present invention, the heterochain polymer of the conductive portion includes at least one of polyurethane, polyurethane acrylate copolymer, epoxy modified polyurethane, polyurethane modified epoxy resin, etc.

[0013] According to some embodiments of the present invention, the rubber material of the main body portion is a carbon chain polymer, and the main body portion includes at least one of nitrile rubber, hydrogenated nitrile rubber, acrylate rubber, polyurethane rubber, ethylene acrylate rubber, ethylene propylene diene monomer rubber, fluororubber, etc.

[0014] According to some embodiments of the present invention, the particle size of the conductive particles is not greater than 20μm; and / or, the conductive particles include at least one of metal particles and carbon-containing particles.

[0015] According to some embodiments of the present invention, the content of the conductive particles in the conductive portion is not less than 50%wt and not greater than 95%wt.

[0016] According to some embodiments of the present invention, a part of the conductive portion is embedded in the rubber material layer; alternatively, the conductive portion is disposed on the outer surface of the main body portion.

[0017] According to some embodiments of the present invention, there are a plurality of the conductive portions, and the plurality of conductive portions are spaced apart and located on the same side or opposite sides of the main body portion.

[0018] According to some embodiments of the present invention, the main body portion includes a surround portion, an outer edge portion disposed outside the surround portion, and an inner edge portion disposed inside the surround portion, and the conductive portion is disposed on the surround portion, the inner edge portion, and the outer edge portion.

[0019] According to some embodiments of the present invention, the conductive portion includes a first electrical connection portion located on the inner edge portion and a second electrical connection portion located on the outer edge portion, the first electrical connection portion is electrically connected to the voice coil, and the second electrical connection portion is electrically connected to the external circuit.

[0020] According to some embodiments of the present invention, the conductive portion further includes a third electrical connection portion disposed on the surround portion, and the first electrical connection portion, the second electrical connection portion, and the third electrical connection portion are all exposed on the outer surface of the main body portion.

[0021] According to some embodiments of the present invention, the main body portion is formed as a single-layer structure composed of the rubber material layer; alternatively, the main body portion is formed as a multi-layer composite structure, the main body portion includes the rubber material layer and the damping layer stacked, the rubber material layer is located on the outermost layer of the main body portion, and the damping layer includes at least one of acrylate pressure-sensitive adhesive, silicone pressure-sensitive adhesive, and polyurethane.

[0022] The sound generating device according to the second aspect embodiment of the present invention includes the diaphragm of any one of the above embodiments.

[0023] The electronic device according to the third aspect embodiment of the present invention includes any one of the above sound generating devices.

[0024] Other features and advantages of the present invention will become clear through the following detailed description of the exemplary embodiments of the present invention with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The drawings incorporated in the specification and constituting a part of the specification illustrate embodiments of the present invention and, together with the description, are used to explain the principles of the present invention.

[0026] Figure 1 It is a partial cross-sectional view of a diaphragm according to an embodiment of the present invention;

[0027] Figure 2Partial cross-sectional view of the diaphragm according to yet another embodiment of the present invention;

[0028] Figure 3 Top view of the sound generating device according to an embodiment of the present invention;

[0029] Figure 4 Schematic structural diagram of the sound generating device according to still another embodiment of the present invention;

[0030] Figure 5 Partial cross-sectional view of the sound generating device according to an embodiment of the present invention;

[0031] Figure 6 Partial cross-sectional view of the sound generating device according to another embodiment of the present invention;

[0032] Figure 7 Comparison graph of the frequency response curves of the comparative example and Example 3 according to the present invention;

[0033] Figure 8 Comparison graph of the total harmonic distortion curves of the comparative example and Example 3 according to the present invention.

[0034] Reference numerals

[0035] Diaphragm 10;

[0036] Main body portion 11; Folded edge portion 111; Outer edge portion 112; Inner edge portion 113; Rubber material layer 114; Damping layer 115;

[0037] Conductive portion 12; Substrate 121; Conductive particles 122;

[0038] Voice coil 20; First diaphragm 21; Second diaphragm 22. Detailed description of the specific embodiments

[0039] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that: Unless otherwise specifically stated, the relative arrangements, numerical expressions, and numerical values of the components and steps set forth in these embodiments do not limit the scope of the present invention.

[0040] The following description of at least one exemplary embodiment is merely illustrative in nature and in no way serves as a limitation on the present invention or its application or use.

[0041] Technologies, methods, and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such technologies, methods, and devices should be regarded as part of the specification.

[0042] In all the examples shown and discussed here, any specific value should be construed as merely exemplary and not as a limitation. Thus, other examples of the exemplary embodiments may have different values.

[0043] It should be noted that like reference numerals and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

[0044] The diaphragm 10 according to an embodiment of the present invention will be specifically described below with reference to the drawings.

[0045] As Figure 1 and Figure 2 shown, the diaphragm 10 according to an embodiment of the present invention includes a main body portion 11 and a conductive portion 12. Among them, the main body portion 11 includes a rubber material layer 114, the conductive portion 12 is disposed on the rubber material layer 114 and at least a part of the conductive portion 12 is exposed outside the main body portion 11 to be electrically connected to the voice coil 20 and an external circuit. The conductive portion 12 includes a matrix 121 and conductive particles 122 dispersed in the matrix 121, and the matrix 121 is composed of a heterochain polymer with -NH-COO- characteristic groups.

[0046] In other words, the diaphragm 10 according to an embodiment of the present invention mainly consists of a main body portion 11 and a conductive portion 12. Among them, the main body portion 11 can serve as the main structure. The main body portion 11 includes a rubber material layer 114 and can be prepared from a rubber material. Since the rubber material has better heat resistance and a lower modulus compared with conventional thermoplastic materials (such as PEEK, TPU, TPEE, etc.), that is to say, the rubber material not only has good high-temperature resistance, weather resistance and high elasticity, but also has a relatively low modulus and can achieve large vibration displacement. Therefore, the diaphragm 10 with the rubber material layer 114 in the main body portion 11 can obtain higher loudness and can meet the requirements of high power and high temperature resistance of the sound generating device products, making the sound generating device have higher loudness, sensitivity and waterproof effect.

[0047] Among them, the conductive part 12 includes a matrix 121 and conductive particles 122. Therefore, the conductive part 12 has electrical conductivity and can achieve circuit conduction. Specifically, at least a part of the surface of the conductive part 12 can be exposed on the surface of the main body part 11 and is electrically connected to the voice coil 20 and the external circuit, solving the problems such as loss of internal vibration space caused by connecting parts such as centering washers in the prior art and easy breakage of the leads of the voice coil 20. Thus, by exposing at least one surface of the conductive part 12 on the surface of the main body part 11, the circuit connection operation is simple. At the same time, due to the existence of the matrix 121 of the conductive part 12, it can protect the conductive particles 122 to a certain extent, and the conductive part 12 has better antioxidant and corrosion resistance properties. Moreover, in the present invention, by combining the matrix 121 and the conductive particles 122, compared with solutions such as pure conductors or surface coatings or coatings, the matrix 121 and the rubber material of the main body part 11 have a strong bonding ability, which is beneficial to the vibration consistency during the operation of the diaphragm 10.

[0048] In addition, the matrix 121 of the conductive part 12 can be used as a binder between the conductive particles 122. The matrix 121 contains a heterochain polymer with a -NH-COO- characteristic group. Since the main chain of the heterochain polymer contains other atoms besides carbon atoms, the material of the conductive part 12 has relatively high polarity and relatively excellent toughness. The heterochain polymer in the conductive part 12 is selected with a -NH-COO- characteristic group because the -NH-COO- characteristic group has strong polarity, which can enhance the binding force between the heterochain polymer and the conductive particles 122. The obtained diaphragm 10 has higher flexibility and better vibration consistency, and can meet the requirements of large displacement, high loudness, high sensitivity and other requirements of the sound generating device products.

[0049] That is to say, by using a heterochain polymer with a -NH-COO- characteristic group as the matrix 121 in the conductive part 12, a better binding effect between the matrix 121 and the conductive particles 122 in the conductive part 12 can be achieved, increasing the interaction force between the matrix 121 and the conductive particles 122, and ensuring the consistency and conductive stability during the vibration process. Specifically, when the diaphragm 10 vibrates at a high temperature, since the matrix 121 of the conductive part 12 contains a heterochain polymer with a -NH-COO- characteristic group, the heterochain polymer in the matrix 121 can play a good role as a link, be able to connect the conductive particles 122 into a whole, so as to achieve the uniform arrangement of the conductive particles 122, and at the same time ensure the conductive consistency and stability of the conductive part 12.

[0050] Thus, the diaphragm 10 according to the embodiment of the present invention combines the main body portion 11 and the conductive portion 12, which not only realizes the electrical connection between the voice coil 20 and the external circuit, but also avoids the problems of loss of internal space caused by connecting members such as centering washers and easy breakage of the lead wires. In addition, the matrix 121 of the conductive portion 12 contains a heterochain polymer with a -NH-COO- characteristic group, and the main body portion 11 is made of a rubber material, which not only enables the conductive portion 12 to have good adhesion to the main body portion 11, but also can enhance the bonding force between the matrix 121 and the conductive particles 122, ensuring the consistency of the diaphragm 10 during the stretching process, thereby realizing good resilience of the diaphragm 10 and ensuring the sound quality stability of the diaphragm 10 during long-term use. The diaphragm 10 is suitable for sound generating devices with requirements of large displacement and high resilience (such as high loudness, deep waterproofing, etc.).

[0051] According to an embodiment of the present invention, the thickness of the diaphragm 10 is 30 μm to 200 μm, which can ensure the stiffness and conductivity of the conductive portion 12. It should be noted that since the main body portion 11 is made of a rubber material, the modulus of the main body portion 11 is generally lower than 100 MPa. In this embodiment, by controlling the thickness of the diaphragm 10 to be 30 μm to 200 μm, it is beneficial for the diaphragm 10 to obtain a suitable resonance frequency.

[0052] In addition, since the conductive portion 12 is exposed on one surface of the main body portion 11 and is part of the vibration of the diaphragm 10, the stiffness of the conductive portion 12 is likely to affect the compliance of the diaphragm 10. If the thickness of the conductive portion 12 is too thick, although the conductivity of the conductive portion 12 is high, the rigidity of the conductive portion 12 is too large, which makes the vibration consistency of the diaphragm 10 liable to deteriorate, and in addition, it limits the stretching deformation of the diaphragm 10. If the thickness of the conductive portion 12 is too thin, it is liable to be limited by the processing technology, and it is difficult to effectively ensure the thickness consistency and uniformity of the diaphragm 10, resulting in unstable conductivity of the conductive portion 12, and cracks are also liable to appear during the vibration of the diaphragm 10, causing the risk of increased resistance.

[0053] Moreover, since the main body portion 11 of the diaphragm 10 is made of a rubber material and the rubber material has a relatively low modulus, to meet the stiffness required for the product F0 and vibration, a certain thickness is required. However, the thicker the thickness, the more the vibration space of the product will be lost, which does not meet the development trend of product ultra-thinness. At the same time, since the conductive portion 12 contains conductive particles 122, the flexibility of the conductive portion 12 is insufficient. If an embedded structure is adopted, if the thickness of the main body portion 11 is too thin, it is liable to cause insufficient toughness of the diaphragm 10 at the conductive portion 12 and the risk of membrane breakage.

[0054] Therefore, in this embodiment, by controlling the thickness of the conductive part 12 to be 0.5 μm to 50 μm, such as 0.5 μm, 5 μm, 20 μm, 30 μm, 40 μm, 50 μm, etc., the influence of the conductive part 12 on vibration is reduced, and good vibration consistency is ensured.

[0055] Optionally, the thickness of the conductive part 12 is 2 μm to 25 μm, which is not only convenient for processing and manufacturing, ensures the thickness consistency and uniformity of the diaphragm 10, but also can ensure the conductivity of the conductive part 12, while avoiding excessive rigidity of the conductive part 12. When the conductive part 12 with this thickness is applied to the diaphragm 10, the service life of the diaphragm 10 can be extended, and cracks and other situations can be avoided when the diaphragm 10 is used for a long time.

[0056] Optionally, while the thickness of the diaphragm 10 is 30 μm to 200 μm, the thickness of the conductive part 12 is 0.5 μm to 50 μm, which can further ensure the toughness and conductivity of the conductive part 12.

[0057] In some specific embodiments of the present invention, the part of the main body part 11 facing the conductive part 12 and the conductive part 12 together form a composite part. When the composite part is under a tensile strain of 20%, there is no delamination between the conductive part 12 and the main body part 11, and the elastic recovery rate of the composite part is greater than 70%.

[0058] In other words, the orthographic projection area of the conductive part 12 on the main body part 11 is defined as the first area. A composite part is formed between the part of the main body part 11 in the first area and the conductive part 12. After the composite part is stretched by 20% strain, there is no delamination between the conductive part 12 and the main body part 11, and the elastic recovery force is greater than 70%. It can be seen that by using the material of the main body part 11 and the heterochain polymer in the conductive part 12 in combination, good interfacial adhesion can be achieved, ensuring consistency during the vibration stretching process, thereby realizing good resilience of the diaphragm 10 and ensuring the sound quality stability of the diaphragm 10 during long-term use.

[0059] In some specific embodiments of the present invention, the heterochain polymer of the conductive part 12 includes at least one of polyurethane, polyurethane acrylate copolymer, epoxy modified polyurethane, polyurethane modified epoxy resin, etc. In this embodiment, by using the conductive part 12 including the above heterochain polymer, it is beneficial for the conductive part 12 and the main body part 11 to have a strong bonding force, thereby realizing the vibration consistency of the diaphragm 10 during vibration.

[0060] According to an embodiment of the present invention, the rubber material of the main body part 11 is a carbon chain polymer, and the main body part 11 includes at least one of nitrile rubber, hydrogenated nitrile rubber, acrylate rubber, polyurethane rubber, ethylene acrylate rubber, ethylene propylene diene monomer rubber, fluororubber, etc.

[0061] In this embodiment, the rubber material is a carbon chain polymer. Using a carbon chain polymer for the main body 11 can achieve good adhesion with the heterochain polymer in the conductive part 12, ensuring the adhesion of the conductive part 12, and thus realizing the vibration consistency of the diaphragm 10 during vibration and the reliability of the diaphragm 10 product.

[0062] In some specific embodiments of the present invention, the particle size of the conductive particles 122 is not greater than 20 μm, which can enable the conductive part 12 to have both high conductivity and flexibility. It should be noted that the particle size of the conductive particles 122 affects the resistivity and flexibility of the conductive part 12. If the particle size of the conductive particles 122 is too large, it will lead to insufficient toughness of the conductive part 12 and is prone to breakage during vibration.

[0063] Among them, when the diaphragm 10 is made of the rubber material of the main body 11 of the diaphragm 10, if the conductive part 12 itself has insufficient toughness and insufficient bonding force with the rubber material of the main body 11, it will result in insufficient flexibility of the diaphragm 10 and the risk of cracks or even breakage of the conductive part 12 during vibration, leading to circuit connection failure.

[0064] Therefore, in this embodiment, by controlling the particle size of the conductive particles 122 to be not greater than 20 μm, for example, the particle size of the conductive particles 122 is 5 μm, 10 μm, 12 μm, 15 μm, 20 μm, etc., it can ensure the toughness and conductivity of the conductive part 12, so that the diaphragm 10 can have both good conductive effect and conductive stability, and improve the toughness of the diaphragm 10 and extend the service life of the diaphragm 10.

[0065] In some specific embodiments of the present invention, the conductive particles 122 include at least one of metal particles and carbon-containing particles. Among them, the metal particles can be at least one of gold, silver, copper, nickel, zinc, aluminum, etc. The carbon-containing particles can be at least one of graphene, carbon black, carbon nanotubes, etc. In this embodiment, by using metal particles and / or carbon-containing particles as the conductive particles 122, it is beneficial to ensure the high conductivity of the conductive particles 122.

[0066] According to an embodiment of the present invention, the content of the conductive particles 122 in the conductive part 12 is not less than 50% wt and not greater than 95% wt, which can enable the conductive part 12 to have both toughness and conductivity. The number of the conductive particles 122 also affects the resistivity and flexibility of the conductive part 12. If the content of the conductive particles 122 is too large, although the resistance of the conductive part 12 is reduced and the conductive performance of the diaphragm 10 is improved, with the increase of the conductive particles 122, it is easy to cause insufficient toughness of the conductive part 12. Therefore, the content of the conductive particles 122 ≤ 95% wt.

[0067] Therefore, in this embodiment, by controlling the content of the conductive particles 122 in the conductive part 12 to be not less than 50% wt and not greater than 95% wt. For example, the content of the conductive particles 122 is 50% wt, 55% wt, 60% wt, 70% wt, etc., it is possible to make the conductive part 12 have both flexibility and high conductivity.

[0068] Optionally, the conductive particles 122 include at least one of metal particles and carbon-containing particles. The conductive particles 122 can be at least one of spherical, quasi-spherical, linear, flaky, dendritic, etc. Among them, the flaky shape is beneficial to controlling the arrangement direction and extension direction of the conductive particles 122, and the flaky conductive particles 122 also have a large surface area. The spherical shape is beneficial to processing and has good conductivity.

[0069] In some specific embodiments of the present invention, a part of the conductive part 12 is embedded in the rubber material layer 114; or, the conductive part 12 is provided on the outer surface of the main body part 11.

[0070] Wherein, when the conductive part 12 is embedded in the main body part 11, a groove can be provided on the main body part 11. A part of the conductive part 12 is provided in the groove of the main body part 11, and the other part of the surface is exposed outside the main body part 11, and the outer surface of the conductive part 12 can be flush with or protrude from the outer surface of the main body part 11. Thus, the diaphragm 10 with this structure can effectively ensure the assembly stability of the conductive part 12 on the main body part 11, and the conductive part 12 is embedded in the main body part 11, which can reduce the thickness of the diaphragm 10 to a certain extent and increase the design space of the product. In addition, the conductive part 12 is embedded in the main body part 11, which can improve the vibration consistency between the conductive part 12 and the main body part 11 and improve the sound production effect of the diaphragm 10.

[0071] That is to say, when adopting the structural design of embedding a part of the conductive part 12 in the rubber material layer 114, the rubber material of the main body part 11 plays a protective role for the conductive part 12 during the vibration process, which can effectively reduce the risk of fracture of the conductive part 12 during vibration and large displacement, and meet the requirements of the diaphragm 10 product for large displacement, high loudness and high sensitivity.

[0072] When the conductive part 12 is provided on the surface of the main body part 11, the conductive part 12 can be coated or adhered to the surface of the main body part 11; alternatively, the main body part 11 and the conductive part 12 are integrally injection-molded. That is to say, when the conductive part 12 is provided on the surface of the main body part 11, there can be various bonding methods between the conductive part 12 and the main body part 11. For example, the conductive part 12 is provided on the surface of the main body part 11 by coating, or the conductive part 12 is provided on the surface of the main body part 11 by bonding, or the conductive part 12 is provided on the surface of the main body part 11 by integral injection molding. Thus, the diaphragm 10 according to the embodiment of the present invention has a simple structure, is convenient to prepare, and can facilitate the electrical connection between the conductive part 12 and the voice coil 20 of the sound generating device or an external circuit.

[0073] According to an embodiment of the present invention, there are a plurality of conductive parts 12, and the plurality of conductive parts 12 are arranged at intervals, and the plurality of conductive parts 12 are located on the same side or opposite sides of the main body part 11. For example, there are two conductive parts 12, the two conductive parts 12 are arranged at intervals, and the two conductive parts 12 are provided on the same side surface or both side surfaces of the main body part 11, and the number and arrangement position of the conductive parts 12 can be selected according to actual usage requirements.

[0074] In other words, the diaphragm 10 of this embodiment may include two or more mutually separated conductive parts 12, and each conductive part 12 is located at the surround part 111 of the diaphragm 10 and the outer edge part 112 and the inner edge part 113 connected thereto. The positive and negative electrodes of the circuit are respectively connected to different conductive parts 12. At the same time, because the conductive part 12 communicates with the surround part 111 and the outer edge part 112 and the inner edge part 113 connected thereto, the circuit connection is easier to operate and has stronger mass production performance. It should be noted that when the number of conductive parts 12 is multiple, some conductive parts 12 can play a balancing role, that is to say, the circuit can selectively electrically connect at least one of the multiple conductive parts 12. Adjacent two conductive parts 12 on the same side can also be connected by leads to control the series-parallel situation and achieve the control of the total resistance.

[0075] According to the actual usage situation of the diaphragm 10, the conductive parts 12 at different parts can be provided on the same surface of the diaphragm 10, or can be designed to be distributed on two surfaces of the diaphragm 10. This is because the design of the conductive part 12 is equivalent to adding a rib structure to the main body part 11 for the main body part 11. When all the conductive parts 12 are distributed on the same side surface of the diaphragm 10, a problem of compliance asymmetry may occur, resulting in a large difference in the up and down amplitudes.

[0076] In some specific embodiments of the present invention, the main body portion 11 includes a surround portion 111, an outer edge portion 112 provided outside the surround portion 111, and an inner edge portion 113 provided inside the surround portion 111. The conductive portion 12 is provided on the surround portion 111, the inner edge portion 113, and the outer edge portion 112. For example, the main body portion 11 is composed of the outer edge portion 112, the surround portion 111, and the inner edge portion 113 from outside to inside, and the conductive portion 12 is provided on the main body portion 11 through the outer edge portion 112, the surround portion 111, and the inner edge portion 113. Thus, in this embodiment, by adopting the surround portion 111, the inner edge portion 113, and the outer edge portion 112, it is convenient to realize the electrical connection of the diaphragm 10 to the voice coil 20 and the external circuit.

[0077] According to an embodiment of the present invention, the conductive portion 12 includes a first electrical connection portion located on the inner edge portion 113 and a second electrical connection portion located on the outer edge portion 112. The first electrical connection portion is electrically connected to the voice coil 20, and the second electrical connection portion is electrically connected to the external circuit. In this embodiment, by cooperating the first electrical connection portion and the second electrical connection portion, the conductive portion 12 is electrically connected to the voice coil 20 and the external circuit, solving the problems such as loss of internal vibration space caused by connecting members such as centering washers in the prior art and easy breakage of the leads of the voice coil 20.

[0078] In some specific embodiments of the present invention, the conductive portion 12 further includes a third electrical connection portion provided on the surround portion 111. The first electrical connection portion, the second electrical connection portion, and the third electrical connection portion are all exposed on the outer surface of the main body portion 11.

[0079] That is to say, the first electrical connection portion is provided on the inner edge portion 113, the second electrical connection portion is provided on the outer edge portion 112, and the third electrical connection portion that can electrically connect the first electrical connection portion and the second electrical connection portion is provided on the surround portion 111. The first electrical connection portion, the second electrical connection portion, and the third electrical connection portion together form the conductive portion 12. Among them, at least a part of the conductive portion 12 can be exposed on the outer surface of the main body portion 11, so as to facilitate electrical connection with the external circuit.

[0080] It should be noted that the electrical connection relationship between the conductive portion 12 and the voice coil 20 and the external circuit is not particularly limited, as long as the effect of being able to electrically connect the voice coil 20 and the external circuit is satisfied. Considering the assembly relationship between the diaphragm 10, the voice coil 20, and the external circuit, the first electrical connection portion can be electrically connected to the voice coil 20, and the second electrical connection portion can be electrically connected to the external circuit.

[0081] In some specific embodiments of the present invention, the main body portion 11 is formed as a single-layer structure composed of a rubber material layer 114; alternatively, the main body portion 11 is formed as a multi-layer composite structure, and the main body portion 11 includes a rubber material layer 114 and a damping layer 115 arranged in a stacked manner. The rubber material layer 114 is located on the outermost layer of the main body portion 11, and the damping layer 115 includes at least one of acrylate pressure-sensitive adhesives, silicone pressure-sensitive adhesives, and polyurethanes.

[0082] That is to say, the main body portion 11 can be either a single-layer structure or a multi-layer composite structure. Among them, when the main body portion 11 adopts a multi-layer composite structure, the diaphragm 10 can be a multi-layer composite structure of a rubber material layer 114 and a damping layer 115. The damping layer 115 can be located inside the main body portion 11, for example, arranged between the rubber material layers 114. The damping layer 115 can play a buffering role, reducing the mutual force between the two rubber material layers 114 during vibration, and effectively solving the problem of delamination during large displacements.

[0083] Compared with the pure rubber material parts of the prior art, the main body portion 11 containing both the rubber material layer 114 and the damping layer 115 has higher damping performance, and the prepared diaphragm 10 also has better anti-polarization ability, and can obtain a lower distortion effect.

[0084] In addition, the damping layer 115 can be selected from at least one of acrylate pressure-sensitive adhesives, silicone pressure-sensitive adhesives, and polyurethanes. By adopting the above-mentioned damping layer 115, it is possible to well balance damping, temperature resistance, resilience, and adhesiveness, ensure the consistency of the vibration of the composite structure, and provide a greater space for the design of the sound generating device product.

[0085] In this embodiment, the main body portion 11 can adopt a single-layer structure or a multi-layer composite structure, which can be set according to needs, and has the advantages of being easy to design and having a wide application range.

[0086] In summary, for the diaphragm 10 according to the embodiment of the present invention, by using the cooperation of the conductive portion 12 and the main body portion 11, and the conductive portion 12 is a heterochain polymer with a -NH-COO- characteristic group, not only realizes the electrical connection between the voice coil 20 and the external circuit, but also avoids the problems of loss of internal space caused by connecting parts such as centering washers and easy breakage of the lead wires. Moreover, the diaphragm 10 provided by the present invention has high elasticity, excellent vibration consistency, and a wider linear vibration region.

[0087] The present invention also provides a sound generating device, which includes the diaphragm 10 of any one of the above embodiments. Since the diaphragm 10 has the above advantages, the sound generating device also has the above advantages. For example, the sound generating device has low distortion, high loudness, and high-fidelity sound quality, which will not be elaborated here.

[0088] It should be noted that the diaphragm 10 provided by the present invention can form a sound generating device with any structure. For example, Figure 5 As shown, a sound generating device according to an embodiment of the present invention includes a housing, a magnetic circuit system provided in the housing, and a vibration system cooperating with the vibration system. The vibration system includes a diaphragm 10 and a voice coil 20 coupled to one side of the diaphragm 10. The magnetic circuit system drives the voice coil 20 to vibrate to drive the diaphragm 10 to generate sound. The diaphragm 10 is the diaphragm 10 of the above embodiment. Specifically, when the sound generating device operates, after the voice coil 20 is energized, under the action of the magnetic field force of the magnetic circuit system, the voice coil 20 can vibrate up and down to drive the diaphragm 10 to vibrate, and the diaphragm 10 can generate sound when vibrating.

[0089] A sound generating device according to another embodiment of the present invention, as Figure 6 shown, includes a housing, a magnetic circuit system provided in the housing, and a vibration system. The vibration system includes a voice coil 20, a first diaphragm 21, and a second diaphragm 22. The top of the voice coil 20 is connected to the first diaphragm 21. The magnetic circuit system drives the voice coil 20 to vibrate to drive the first diaphragm 21 to generate sound. Both ends of the second diaphragm 22 are respectively connected to an external circuit and the bottom of the voice coil 20. The second diaphragm 22 is the diaphragm 10 of the above embodiment.

[0090] That is to say, the sound generating device according to the embodiment of the present invention may further include two diaphragms 10 prepared by the above embodiment of the present invention, namely the first diaphragm 21 and the second diaphragm 22. The first diaphragm 21 can be used for vibrating and generating sound, and the second diaphragm 22 can be used to balance the vibration of the voice coil 20. Specifically, when the sound generating device operates, after the voice coil 20 is energized, under the action of the magnetic field force of the magnetic circuit system, the voice coil 20 can vibrate up and down to drive the first diaphragm 21 to vibrate, and the first diaphragm 21 can generate sound when vibrating. The second diaphragm 22 can also vibrate up and down following the voice coil 20. Since both ends of the second diaphragm 22 are respectively connected to an external circuit and the bottom of the voice coil 20, the second diaphragm 22 can balance the vibration of the voice coil 20, and can prevent the voice coil 20 from being polarized, thereby improving the sound generating effect of the sound generating device.

[0091] It should be noted that the first diaphragm 21 and the second diaphragm 22 can both adopt the diaphragm 10 of the above embodiment of the present invention, or one of the first diaphragm 21 and the second diaphragm 22 can adopt the diaphragm 10 of the above embodiment of the present invention. The present invention does not make specific limitations on this.

[0092] An electronic device according to an embodiment of the present invention includes the sound generating device of the above embodiment, and the sound generating device adopts the diaphragm 10 of the above embodiment. Since the diaphragm 10 according to the above embodiment of the present invention has the above technical effects, therefore, the electronic device according to the embodiment of the present invention also has corresponding technical effects, that is, it can avoid problems such as loss of internal vibration space caused by assembling connecting parts such as centering gaskets and easy breakage of the leads of the voice coil 20 in the prior art, and can meet the requirements of large displacement, high loudness, high sensitivity, etc. of the product.

[0093] The present invention also provides an electronic device, including the sound generating device of any of the above embodiments. Since the sound generating device has the above advantages, the electronic device of the present invention also has the above advantages and will not be elaborated here.

[0094] The following will describe the diaphragm 10 and the sound generating device according to the embodiment of the present invention in detail with reference to specific embodiments.

[0095] In Embodiments 1 to 6, a conductive slurry is used to prepare the conductive part 12. In the matrix 121 of the conductive slurry, there are conductive particles 122. The conductive particles 122 are selected from at least one of a mixture of silver powder and graphene. Among them, the size of the conductive particles 122 is about 50 nm to 10 μm, and the matrix 121 is a polyurethane polymer.

[0096] In the comparative example, an ordinary pure rubber material diaphragm is used, and the voice coil in the comparative example is connected to the external circuit through a lead. The diaphragm in the comparative example is a non-conductive diaphragm and does not have conductive properties.

[0097] The conductive pastes obtained in Embodiments 1 to 6 are respectively printed on a hydrogenated nitrile rubber sheet (thickness about 100 μm) by screen printing (screen mesh count 250 meshes, squeegee hardness 70A), cured at 100 °C for 30 min, and the thickness of the conductive coating after curing is about 7 μm to 15 μm.

[0098] The evaluation method of the elastic recovery rate after 20% strain in Table 1 is to use the tensile mode of a tensile machine or a DMA device. The sample is stretched to 20% strain and then the external force is removed, and then the deformation amount of the sample piece is measured, so as to calculate the elastic recovery rate. At the same time, visually check whether there are cracks or delamination on the surface conductive layer of the tested sample.

[0099] Perform multiple performance tests on the diaphragms 10 obtained in Embodiments 1 to 6 and the pure rubber material diaphragm of the comparative example. Among them, the evaluation method of the elastic recovery rate after 20% strain is to use the tensile mode of a tensile machine or a DMA device. The sample is stretched to 20% strain and then the external force is removed, and then the deformation amount of the sample piece is measured, so as to calculate the elastic recovery rate. At the same time, visually check whether there are cracks or delamination on the surface conductive layer of the tested sample.

[0100] The ingredient ratios and test results of Examples 1 to 6 are summarized in Table 1 below.

[0101] Table 1 Ingredient and Test Results Table

[0102]

[0103]

[0104] As shown in Table 1, Examples 1 to 4 contain the same conductive particles 122, and spherical and flaky mixed silver powder is used. The content of the conductive particles 122 in Example 1 is 93%, the content of the conductive particles 122 in Example 2 is 80%, the content of the conductive particles 122 in Example 3 is 70%, and the content of the conductive particles 122 in Example 4 is 50%. The sheet resistance of Example 1 is not greater than 10 mΩ / □ / 25.4 μm, the sheet resistance of Example 2 is 15 mΩ / □ / 25.4 μm, the sheet resistance of Example 3 is 27 mΩ / □ / 25.4 μm, and the sheet resistance of Example 4 is 80 mΩ / □ / 25.4 μm. It can be seen that as the addition amount of the conductive particles 122 increases, the sheet resistance decreases significantly, indicating an increase in conductivity.

[0105] However, cracks appeared in Example 1 after 20% strain, and the conductive part 12 failed; the elastic recovery rate of Example 2 after 20% strain was 87%, the elastic recovery rate of Example 3 after 20% strain was 98%, and the elastic recovery rate of Example 4 after 20% strain was 95%. It can be seen that as the amount of the conductive particles 122 increases, the elastic recovery rate of the composite part decreases. In particular, the addition amount of the conductive particles 122 in Example 6 is 93%, that is, the addition amount is above 90%.

[0106] In addition, comparing Example 1 and Example 6, spherical and flaky mixed silver powder is used in both Example 1 and Example 6. The coating thickness of Example 1 is 7 μm ± 2 μm, and the coating thickness of Example 6 is 15 μm ± 2 μm. The sheet resistances of Example 1 and Example 6 are not greater than 10 mΩ / □ / 25.4 μm. There are delaminations or cracks in the conductive layer of Example 1 after 20% strain, and there are no delaminations or cracks in the conductive layer of Example 6 after 20% strain. That is to say, the thickness of the conductive part 12 should not be too thin. If the conductive part 12 is too thin, due to the reduced film-forming property of the polyurethane resin, it is easy to cause insufficient toughness between the conductive particles 122.

[0107] Compare Example 2 with Example 5. In Example 2, a mixture of spherical and flaky silver powders is used. In Example 5, a mixture of spherical silver powder and graphene sheets is used. The sheet resistance of Example 2 is 15 mΩ / □ / 25.4 μm, and the sheet resistance of Example 5 is 30 mΩ / □ / 25.4 μm. The elastic recovery rate of Example 2 after 20% strain is 87%, and the elastic recovery rate of Example 5 after 20% strain is 90%. It can be seen that the resistance of the conductive part 12 containing graphene sheets is slightly higher than that of the flaky silver powder. However, in terms of the toughness of the conductive part 12, the graphene sheet solution has a better effect.

[0108] Based on the above results, select the diaphragm 10 design schemes of the comparative example and Example 3, and match the voice coil 20 and the magnetic circuit system, etc., to further manufacture the sound generating device.

[0109] Among them, since the diaphragm 10 of the comparative example cannot conduct electricity, the industry's conventional lead scheme is adopted, that is, the voice coil 20 is connected to the external circuit through a lead. Except for the different point connection methods, the other designs of the comparative example and Example 3 are the same.

[0110] By comparing the acoustic performance of the sound generating device, such as Figure 7 and Figure 8 shown, through the frequency response curve and the total harmonic distortion curve, the following results can be obtained:

[0111] As shown by the frequency response curve, the low-frequency performance of the two schemes has little difference, but Example 3 has a lower resonance frequency F0, and the mid-frequency loudness of Example 3 is slightly lower than that of the comparative example. That is to say, since the resistance of the conductive part 12 of Example 3 is higher than the lead resistance, this shortcoming can be further optimized through the resistance and magnetic circuit design.

[0112] As shown by the total harmonic distortion curve, Example 3 has lower distortion. This phenomenon is related to the fact that the conductive part 12 is provided on the surface of the main body part 11 of the diaphragm 10 and the conductive part 12 is a flexible part. Compared with the lead connection of the comparative example, the conductive part 12 of Example 3 has higher compliance and can vibrate together with the main body part 11 of the diaphragm 10, and the vibration consistency is better, so that lower distortion can be obtained.

[0113] In summary, compared with the prior art that adopts a pure rubber diaphragm and a common electrical connection scheme, since the diaphragm 10 of the present invention has a conductive portion 12, the diaphragm 10 has electrical conductivity, thereby solving the problem that the conventional voice coil is electrically connected to an external circuit through a voice coil lead and is extremely prone to short circuit during vibration. Moreover, the diaphragm 10 in the present invention can also not be provided with a centering washer in the vibration system, and the structure of the vibration system is simpler. By defining the materials of the conductive portion 12 and the main body portion 11, the bonding force between the conductive portion 12 and the main body portion 11 is better, and the vibration consistency is better, so that the high resilience of the diaphragm 10 when using the conductive portion 12 as an electrical connection can be better realized, and the requirement for large-amplitude vibration can be met. The present invention also provides a sounding device and an electronic device. The sounding device includes the diaphragm 10 of any of the above embodiments. Since the diaphragm 10 has the above advantages, the sounding device also has the above advantages and will not be elaborated herein.

[0114] Although some specific embodiments of the present invention have been described in detail by way of examples, those skilled in the art should understand that the above examples are only for illustration and not for limiting the scope of the present invention. Those skilled in the art should understand that the above embodiments can be modified without departing from the scope and spirit of the present invention. The scope of the present invention is defined by the appended claims.

Claims

1. A diaphragm, characterized in that, It includes a main body part and a conductive part. Among them, the main body part includes a rubber material layer. The conductive part is disposed in the rubber material layer and at least a part of the conductive part is exposed outside the main body part to be electrically connected to the voice coil and an external circuit. The conductive part includes a matrix and conductive particles dispersed in the matrix. The matrix is composed of a heterochain polymer with a -NH-COO- characteristic group; The part of the main body part opposite to the conductive part and the conductive part together form a composite part. When the tensile strain of the composite part is 20%, there is no delamination between the conductive part and the main body part, and the elastic recovery rate of the composite part is greater than 70%; The particle size of the conductive particles is not greater than 20 μm; The content of the conductive particles in the conductive part is not less than 50%wt and not greater than 95%wt.

2. The diaphragm according to claim 1, characterized in that, The thickness of the diaphragm is 30 μm to 200 μm, and the thickness of the conductive part is 0.5 μm to 50 μm.

3. The diaphragm according to claim 1, wherein, The heterochain polymer of the conductive part includes at least one of polyurethane, polyurethane acrylate copolymer, epoxy modified polyurethane, and polyurethane modified epoxy resin.

4. The diaphragm according to claim 1, wherein, The rubber material of the main body part is a carbon chain polymer. The main body part includes at least one of nitrile rubber, hydrogenated nitrile rubber, acrylate rubber, polyurethane rubber, ethylene acrylate rubber, and fluororubber of ethylene propylene diene monomer.

5. The diaphragm according to claim 1, characterized in that The conductive particles include at least one of metal particles and carbon-containing particles.

6. The diaphragm according to claim 1, characterized in that, A part of the conductive part is embedded in the rubber material layer; Or, the conductive part is disposed on the outer surface of the main body part.

7. The diaphragm according to claim 1, wherein There are multiple conductive parts, and the multiple conductive parts are arranged at intervals. The multiple conductive parts are located on the same side or opposite sides of the main body part.

8. The diaphragm according to claim 1, characterized in that, The main body part includes a surround part, an outer edge part disposed outside the surround part, and an inner edge part disposed inside the surround part. The conductive part is disposed on the surround part, the inner edge part, and the outer edge part.

9. The diaphragm according to claim 8, characterized in that, The conductive part includes a first electrical connection part located on the inner edge part and a second electrical connection part located on the outer edge part. The first electrical connection part is electrically connected to the voice coil, and the second electrical connection part is electrically connected to the external circuit.

10. The diaphragm according to claim 9, wherein The conductive part further includes a third electrical connection part disposed on the surround part. The first electrical connection part, the second electrical connection part, and the third electrical connection part are all exposed outside the outer surface of the main body part.

11. The diaphragm according to any one of claims 1-10, characterized in that, The main body part is formed into a single-layer structure composed of the rubber material layer; Or, the main body part is formed into a multi-layer composite structure. The main body part includes the rubber material layer and a damping layer arranged in a stacked manner. The rubber material layer is located on the outermost layer of the main body part. The damping layer includes at least one of acrylate-based pressure-sensitive adhesives, silicone-based pressure-sensitive adhesives, and polyurethanes.

12. A sound generating device, characterized in that, It includes the diaphragm according to any one of claims 1-11.

13. An electronic device, characterized in that, It includes the sound generating device according to claim 12.

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