Vibrating diaphragm assembly, sound production device and electronic equipment

Abstract

The invention belongs to the technical field of electroacoustics, and particularly relates to a vibrating diaphragm assembly, a sound production device and electronic equipment, the vibrating diaphragm assembly comprises a vibrating diaphragm, a globe roof and a bonding layer arranged between the vibrating diaphragm and the globe roof, the bonding layer is a blending system, the blending system comprises reinforced resin and a modified polystyrene-poly (ethylene-butylene)-polystyrene block copolymer, the reinforced resin accounts for 0.5%-60% of the total mass of the bonding layer, and the elastic modulus of the bonding layer is 20-800 MPa at the temperature of 25 DEG C; and / or under the condition of 120 DEG C, the elastic modulus of the bonding layer is 0.05 MPa to 5 MPa. The bonding layer in the diaphragm assembly is a blending system, so that the modulus stability of the bonding layer in a high-temperature state is remarkably improved, and the mechanical property of the bonding layer at normal temperature and the working stability of the bonding layer in the high-temperature state are improved.

Description

Technical Field

[0001] The present invention belongs to the field of electroacoustic technology, and in particular relates to a diaphragm assembly, a sound-generating device and an electronic device. Background Art

[0002] The diaphragm and the dome of the diaphragm assembly of the sound-generating device are usually fixed by an adhesive layer. The main resin of the adhesive layer is mostly polyurethane, acrylic acid, polystyrene, polyacrylate and ethylene-vinyl acetate copolymer, etc. The long-term working temperature of the main resin is below 100°C.

[0003] As the speaker power and voltage increase, the voice coil does more work, and the heat generation increases significantly. The heat generated cannot be dissipated in time, and the product temperature can reach over 130°C. Therefore, the temperature resistance of the diaphragm assembly becomes particularly important. However, the elastic modulus of the existing adhesive layer is low at high temperatures, which causes the adhesive layer to crack during high-frequency vibration. That is, the working stability of the existing diaphragm assembly is very poor at high temperatures and cannot work normally.

[0004] To this end, the present invention is proposed. Summary of the invention

[0005] The main purpose of the present invention is to provide a diaphragm assembly, a sound-emitting device and an electronic device. The adhesive layer in the diaphragm assembly of the present invention has a reinforcing resin and a modified polystyrene-poly(ethylene-butylene)-polystyrene block copolymer, which significantly improves the modulus stability of the adhesive layer under high temperature conditions, and improves the mechanical properties of the adhesive layer under normal temperature conditions and the working stability under high temperature conditions.

[0006] In order to achieve the above objectives, the present invention provides the following technical solutions.

[0007] In a first aspect of the present invention, a diaphragm assembly is provided, which includes a diaphragm, a dome, and an adhesive layer disposed between the diaphragm and the dome, wherein the adhesive layer is a blended system, and the blended system includes a reinforcing resin and a modified polystyrene-poly(ethylene-butylene)-polystyrene block copolymer, the mass percentage of the reinforcing resin in the total mass of the adhesive layer is 0.5% to 60%, and at 25°C, the elastic modulus of the adhesive layer is 20MPa to 800MPa; and / or, at 120°C, the elastic modulus of the adhesive layer is 0.05MPa to 5MPa.

[0008] In some embodiments of the present invention, the mass percentage of the reinforcing resin in the bonding layer is 1% to 10%.

[0009] In some embodiments of the present invention, at 120° C., the elastic modulus of the bonding layer is 1 MPa to 2 MPa.

[0010] In some embodiments of the present invention, at 25° C., the ejection force per unit area of ​​the diaphragm assembly is 4N to 30N.

[0011] In some embodiments of the present invention, at 25° C., the ejection force per unit area of ​​the diaphragm assembly is 10N to 30N.

[0012] In some embodiments of the present invention, the diaphragm and the dome are bonded together through the bonding layer at a bonding temperature of 100° C. to 200° C. and a bonding time of 5 s to 60 s.

[0013] In some embodiments of the present invention, the bonding temperature of the diaphragm and the dome through the bonding layer is 150° C. to 180° C.

[0014] In some embodiments of the present invention, after being treated at 120° C. for 3 hours, the thickness shrinkage rate of the adhesive layer is ≤3%.

[0015] In some embodiments of the present invention, after being treated at 120° C. for 3 hours, the thickness shrinkage rate of the adhesive layer is ≤1%.

[0016] In some embodiments of the present invention, the thickness of the adhesive layer is 10 μm to 100 μm.

[0017] In some embodiments of the present invention, the thickness of the diaphragm assembly is 60 μm to 300 μm.

[0018] In some embodiments of the present invention, the modified polystyrene-poly(ethylene-butylene)-polystyrene block copolymer contains a benzene ring and a functional group, and the functional group includes at least one of an epoxy group, a styrene group, an ester group, and an acid anhydride.

[0019] In some embodiments of the present invention, the molar ratio of the functionalized group to the benzene ring in the modified polystyrene-poly(ethylene-butylene)-polystyrene block copolymer is (0.05-5):100.

[0020] In some embodiments of the present invention, the modified polystyrene-poly(ethylene-butylene)-polystyrene block copolymer is obtained by grafting a polystyrene-poly(ethylene-butylene)-polystyrene block copolymer with an active compound containing a functional group.

[0021] In some embodiments of the present invention, the active compound containing a functional group is selected from at least one of glycidyl methacrylate, 1,2-epoxy-4-vinylcyclohexane, 2,3-epoxypropyltrimethylammonium chloride, polystyrene, and maleic anhydride.

[0022] In some embodiments of the present invention, the reinforcing resin is selected from at least one of polyethylene, polypropylene, polyphenylene ether, polycarbonate, polyetheretherketone, polyarylate, polystyrene, thermoplastic polyester elastomer, thermoplastic polyurethane elastomer rubber, and nylon elastomer.

[0023] In some embodiments of the present invention, the material of the diaphragm is selected from at least one of engineering plastics and elastomeric materials; and / or the material of the dome is selected from at least one of carbon fiber, aluminum metal, aluminum-based composite materials and engineering plastics.

[0024] A second aspect of the present invention provides a sound-generating device, wherein the sound-generating device comprises the diaphragm assembly described in the first aspect.

[0025] According to a third aspect of the present invention, an electronic device is provided. The electronic device includes the sound-generating device according to the second aspect.

[0026] Compared with the prior art, the present invention achieves the following technical effects:

[0027] The adhesive layer in the diaphragm assembly of the present invention has reinforcing resin and modified polystyrene-poly(ethylene-butylene)-polystyrene block copolymer, which significantly improves the modulus stability of the adhesive layer under high temperature conditions, and improves the room temperature mechanical properties of the adhesive layer and the working stability under high temperature conditions.

[0028] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference numerals are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0030] Figure 1 is a cross-sectional view of a diaphragm assembly according to some embodiments of the present invention;

[0031] Figure 2 is a cross-sectional view of a sound-generating device according to some embodiments of the present invention;

[0032] Figure 3 Schematic diagram of THD curves of the speakers corresponding to the diaphragm assemblies in Example 1 and Comparative Example 2.

[0033] Reference numerals

[0034] 100, diaphragm assembly;

[0035] 110, diaphragm; 120, dome; 130, bonding layer;

[0036] 200. Sound-generating device;

[0037] 210, housing; 220, magnetic circuit system; 230, voice coil. DETAILED DESCRIPTION

[0038] The exemplary embodiments of the present invention will be described in more detail below with reference to specific embodiments. It should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to enable the scope of the present invention to be fully communicated to those skilled in the art.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which the present invention belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention; the terms "including" and "having" in the specification and claims of the present invention and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions.

[0040] In the description of the embodiments of the present invention, technical terms such as "first" and "second" are only used to distinguish different objects and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features.

[0041] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0042] In the description of the embodiments of the present invention, the term "and / or" is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists, A and B exist at the same time, and B exists. In addition, the character " / " in this document generally indicates that the associated objects before and after are in an "or" relationship.

[0043] In the description of the embodiments of the present invention, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0044] In the description of the embodiments of the present invention, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the embodiments of the present invention.

[0045] In the description of the embodiments of the present invention, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0046] The present invention provides a diaphragm assembly, such as Figure 1 As shown, the diaphragm assembly 100 includes a diaphragm 110, a dome 120 and an adhesive layer 130 disposed between the diaphragm 110 and the dome 120, the adhesive layer 130 is a blended system, the blended system includes a reinforcing resin and a modified polystyrene-poly(ethylene-butylene)-polystyrene block copolymer, the mass percentage of the reinforcing resin to the total mass of the adhesive layer is 0.5% to 60%, at 25°C, the elastic modulus of the adhesive layer is 20MPa to 800MPa; and / or, at 120°C, the elastic modulus of the adhesive layer is 0.05MPa to 5MPa.

[0047] Reinforced resin has excellent high temperature mechanical properties, wear resistance, self-lubrication, corrosion resistance and good molding processability. Therefore, reinforcing resin is introduced into the modified polystyrene-poly (ethylene-butylene)-polystyrene block copolymer matrix of the present invention, which increases the degree of mutual entanglement between molecular chains, thereby reducing the free volume of the blending system, and the formed molecular chains are more stable, thereby increasing the high temperature modulus of the blending system and improving the temperature resistance effect. In an embodiment of the present invention, the mass percentage of the reinforcing resin to the total mass of the bonding layer is 0.5% to 60%. When the reinforcing resin content is less than 0.5%, the temperature resistance effect is not significantly improved; when the reinforcing resin content is greater than 60%, the compatibility and stability of the blending system are affected. The compatibility principle of polymer blends shows that the blending between different polymer components requires compatible compatibility. Too much reinforcing resin addition will destroy the compatibility of the system, resulting in poor compatibility of the blending system, thereby affecting its stability and service life.

[0048] In some embodiments of the present invention, the mass percentage of the reinforcing resin in the bonding layer is 1% to 10%. This further improves the high temperature modulus of the blended system and improves the temperature resistance of the bonding layer. Exemplarily, the mass percentage of the reinforcing resin in the bonding layer can be 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 20%, 30%, 40%, 50%, 60% or any value that meets the above range.

[0049] The elastic modulus of the adhesive layer in the present invention refers to the ability to resist deformation when deformed by force. In an embodiment of the present invention, the elastic modulus of the adhesive layer is 20MPa to 800MPa at 25°C. If the modulus of the adhesive layer is less than 20MPa, the adhesive layer body may crack when the sound-emitting device such as a speaker works for a long time; and if the elastic modulus of the adhesive layer is greater than 800MPa, greater stress may be caused during the speaker production process, leading to stress concentration, especially when excessive pressure is applied, which may cause the diaphragm to deform or rupture. Illustratively, at 25°C, the elastic modulus of the adhesive layer can be one of 20MPa, 30MPa, 40MPa, 50MPa, 60MPa, 70MPa, 80MPa, 90MPa, 100MPa, 150MPa, 200MPa, 250MPa, 300MPa, 350MPa, 400MPa, 450MPa, 500MPa, 550MPa, 600MPa, 650MPa, 700MPa, 750MPa, 800MPa or any value that meets the above range.

[0050] In the embodiment of the present invention, at 120°C, the elastic modulus of the bonding layer is 0.05MPa to 5MPa. When the elastic modulus of the bonding layer is less than 0.05MPa, at high temperatures, the main resin molecular chains of the bonding layer break and the cross-linking structure changes, thereby reducing its bonding strength and performance, and causing the bonding layer to crack during high-frequency vibration. When the elastic modulus of the bonding layer is greater than 5MPa, during the speaker production process, it will cause greater stress, resulting in stress concentration, and it is easy for the diaphragm and the dome to crack, resulting in split vibration.

[0051] In some embodiments of the present invention, the elastic modulus of the adhesive layer is 1 MPa to 2 MPa at 120° C. This further improves the modulus stability of the adhesive layer at high temperatures and improves the reliability of the diaphragm assembly.

[0052] In the present invention, the ejection force of the adhesive layer represents the size of the bonding force between the diaphragm and the dome. When the ejection force is small, the bonding force between the diaphragm and the dome is small, and the product reliability is low. In an embodiment of the present invention, at 25°C, the ejection force of the diaphragm assembly per unit area is 4N to 30N. Thus, a diaphragm assembly with higher reliability is obtained. Exemplarily, at 25°C, the ejection force of the diaphragm assembly per unit area can be one of 4N, 5N, 6N, 7N, 8N, 9N, 10N, 11N, 12N, 13N, 14N, 15N, 16N, 17N, 18N, 19N, 20N, 21N, 22N, 23N, 24N, 25N, 26N, 27N, 28N, 29N, 30N or any value that satisfies the above range.

[0053] In some embodiments of the present invention, at 25° C., the ejection force per unit area of ​​the diaphragm assembly may be 10 N to 30 N. This further improves the bonding force between the diaphragm and the dome, and obtains a diaphragm assembly with higher reliability.

[0054] In an embodiment of the present invention, the reinforcing resin is selected from at least one of polyethylene (PE), polypropylene (PP), polyphenylene oxide (PPO), polycarbonate (PC), polyetheretherketone (PEEK), polyarylate (PAR), polystyrene (PS), thermoplastic polyester elastomer (TPEE), thermoplastic polyurethane elastomer rubber (TPU), and nylon elastomer (TPAE), thereby improving the modulus stability of the adhesive layer under high temperature conditions.

[0055] In an embodiment of the present invention, the modified polystyrene-poly(ethylene-butylene)-polystyrene block copolymer contains a benzene ring and a functional group, and the functional group includes at least one of an epoxy group, a styrene group, an ester group, and an acid anhydride.

[0056] Epoxy Group

[0057] The epoxy group and the reinforcing resin produce intermolecular van der Waals forces, and also form a certain degree of hydrogen bonds. At the bonding temperature, the epoxy group will produce a "ring-opening" reaction, thereby obtaining a higher bonding force through intramolecular covalent bonds, thereby increasing the connection strength between the diaphragm and the dome, and improving the ejection force of the diaphragm assembly.

[0058] Styrene

[0059] The styrene group limits the movement of the molecular chain by increasing the degree of cross-linking, thereby improving the heat resistance of the material, thereby improving the temperature resistance of the adhesive layer, and further improving the working stability of the diaphragm assembly under high temperature conditions.

[0060] Ester and anhydride

[0061] The polystyrene-poly(ethylene-butylene)-polystyrene block copolymer does not contain polar groups or reactive groups on its molecular chain. When blended with polar reinforcing resins, the compatibility between them is poor. Therefore, functionalization is required to improve the compatibility with polar polymers and enhance the blending effect between reinforcing resins and modified polystyrene-poly(ethylene-butylene)-polystyrene.

[0062] In the present invention, the grafting efficiency limits the content of the functionalized groups. When the content of the functionalized groups is low, the improvement effect is not obvious. In an embodiment of the present invention, the molar ratio of the functionalized groups to the benzene rings in the modified polystyrene-poly(ethylene-butylene)-polystyrene block copolymer is (0.05-5):100. This further achieves a better adhesion between the diaphragm and the dome without affecting the preparation efficiency. Illustratively, the molar ratio of the functionalized group to the benzene ring can be one of 0.05:100, 0.06:100, 0.07:100, 0.08:100, 0.09:100, 0.1:100, 0.2:100, 0.3:100, 0.4:100, 0.5:100, 0.6:100, 0.7:100, 0.8:100, 0.9:100, 1:100, 2:100, 3:100, 4:100, 5:100 or any value satisfying the above range.

[0063] In some embodiments of the present invention, the modified polystyrene-poly(ethylene-butylene)-polystyrene block copolymer (SEBS) is obtained by grafting a polystyrene-poly(ethylene-butylene)-polystyrene block copolymer with an active compound containing a functional group. SEBS has low density, good weather resistance, heat resistance, compression deformation resistance, excellent mechanical properties, aging resistance, and elastomeric properties that can be used without vulcanization. SEBS and an active compound containing a functional group are grafted to obtain functional groups, such as epoxy groups, through a grafting reaction. The epoxy groups generate intermolecular van der Waals forces with the reinforcing resin, and also form a certain degree of hydrogen bonds. At the bonding temperature, the epoxy groups will produce a "ring opening" reaction, thereby obtaining a higher bonding force through intramolecular covalent bonds, thereby improving the bonding force of the bonding layer and enhancing the structural firmness between the diaphragm and the dome.

[0064] In some embodiments of the present invention, the active compound containing a functional group is selected from at least one of glycidyl methacrylate, 1,2-epoxy-4-vinylcyclohexane, 2,3-epoxypropyltrimethylammonium chloride, polystyrene, and maleic anhydride, thereby achieving a better bonding strength between the diaphragm and the dome, and improving the reliability of the diaphragm assembly.

[0065] In the present invention, SEBS grafting is a free radical reaction, in which monomers and oligomers are grafted onto the SEBS molecular chain, and the grafting position is on the unhydrogenated double bonds. Taking the grafting reaction of SEBS and glycidyl methacrylate as an example, the grafting reaction principle is shown in the following formula (1).

[0066]

[0067] In some embodiments of the present invention, the material of the diaphragm is selected from at least one of engineering plastics and elastomeric materials. For example, the material of the diaphragm can be a composite of one or more materials selected from polyetheretherketone (PEEK), polyimide (PI), thermoplastic polyurethane elastomer rubber (TPU), thermoplastic polyester elastomer (TPEE), rubber, etc.

[0068] In some embodiments of the present invention, the material of the dome is selected from at least one of carbon fiber, aluminum metal, aluminum-based composite materials and engineering plastics. For example, the material of the dome can be one of carbon fiber, aluminum metal, aluminum-based composite materials, polyetheretherketone (PEEK), and polyimide (PI).

[0069] The dimensional stability of the adhesive layer in the present invention is crucial to the performance of the diaphragm assembly, and directly affects the sound transmission quality and the service life of the diaphragm assembly. The thickness change of the adhesive layer at high temperature will weaken the bonding strength, reduce heat resistance, increase fluidity, and affect the size change of the product, resulting in discrete data on the product frequency response and sensitivity, affecting the sound transmission quality and the service life of the diaphragm assembly. In an embodiment of the present invention, after baking at 120°C for 3 hours, the thickness shrinkage rate of the adhesive layer is ≤3%, for example, the thickness shrinkage rate of the adhesive layer is 0 to 3%. Exemplarily, after baking at 120°C for 3 hours, the thickness shrinkage rate of the adhesive layer can be one of 0%, 1%, 2%, 3%, or any value that satisfies the above range.

[0070] The calculation of the shrinkage rate of the adhesive layer thickness in the present invention is as follows:

[0071] ((initial thickness of the adhesive layer - thickness of the adhesive layer after baking at 120° C. for 3 hours) / initial thickness)*100%.

[0072] In some embodiments of the present invention, after baking at 120° C. for 3 hours, the thickness shrinkage rate of the adhesive layer is 0-1%, thereby further improving the dimensional stability of the adhesive layer and the reliability of the diaphragm assembly.

[0073] In the present invention, the thickness of the adhesive layer needs to be appropriate, and the thickness of the adhesive layer is 10μm to 100μm. If the thickness of the adhesive layer is greater than 100μm, the vibration space of the sound-generating device such as a speaker is reduced, and the maximum amplitude that can be achieved is reduced, which affects the sound effect of the sound-generating device; and if the thickness of the adhesive layer is less than 10μm, the bonding effect of the adhesive layer is poor, and the ejection force of the diaphragm assembly is low, resulting in reduced reliability of the speaker. Exemplarily, the thickness of the adhesive layer can be one of 10μm, 20μm, 30μm, 40μm, 50μm, 60μm, 70μm, 80μm, 90μm, 100μm, or any value that meets the above range.

[0074] In some embodiments of the present invention, the thickness of the adhesive layer may be 20 μm to 40 μm, thereby further improving the reliability of the diaphragm assembly.

[0075] In some embodiments of the present invention, the thickness of the diaphragm assembly may be 60 μm to 300 μm. For example, the thickness of the diaphragm assembly may be 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm, 160 μm, 170 μm, 180 μm, 190 μm, 200 μm, 210 μm, 220 μm, 230 μm, 240 μm, 250 μm, 260 μm, 270 μm, 280 μm, 290 μm, 300 μm or any value satisfying the above range.

[0076] The bonding temperature between the diaphragm and the dome in the present invention, that is, the bonding temperature of the bonding layer, directly affects the bonding efficiency of the bonding layer. In an embodiment of the present invention, the bonding temperature of the diaphragm and the dome through the bonding layer is 100°C to 200°C. If the bonding temperature is less than 100°C, the viscosity of the bonding layer is high and the fluidity is poor, and it cannot fully penetrate into the gaps of the adhered objects, resulting in a slower bonding speed and poorer bonding effect. If the temperature is greater than 200°C, the bonding layer will undergo thermal decomposition, and the diaphragm will also be damaged, affecting the flatness of the diaphragm. Exemplarily, the bonding temperature can be one of 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C, 200°C, or any value that satisfies the above range.

[0077] In some embodiments of the present invention, the bonding temperature of the diaphragm and the dome through the bonding layer may be 150° C. to 180° C. This further achieves better bonding effect and bonding efficiency.

[0078] In an embodiment of the present invention, the bonding time may be 5s to 60s, thereby achieving a better bonding effect. Exemplarily, the bonding time may be one of 5s, 6s, 7s, 8s, 9s, 10s, 15s, 20s, 25s, 30s, 35s, 40s, 45s, 50s, 55s, 60s, or any value satisfying the above range.

[0079] The present invention also provides a sound-generating device, which includes a diaphragm assembly according to any of the above embodiments. Since the diaphragm assembly in the present invention has the advantage of high reliability, it can improve the sound quality of the sound-generating device, thereby improving the overall stability and sound-generating effect of the sound-generating device.

[0080] The diaphragm assembly provided by the present invention can be used to form a sound-generating device of any structure, such as the following typical sound-generating devices: Figure 2As shown, the sound-generating device 200 may be a speaker, which includes a housing 210, a vibration system disposed in the housing 210, and a magnetic circuit system 220 matched with the vibration system, wherein the vibration system includes a diaphragm assembly 100 and a voice coil 230 coupled to one side of the diaphragm assembly 100. When the sound-generating device 200 is working, after the voice coil 230 is energized, under the action of the magnetic field force of the magnetic circuit system 220, the voice coil 230 may vibrate up and down to drive the diaphragm assembly 100 to generate sound.

[0081] The present invention also provides an electronic device having a sound-generating device according to any of the above embodiments. The electronic device has a sound-generating device 200, thereby achieving the advantages of high stability and reliability of the electronic device and improved sound-generating effect. Optionally, the electronic device can be a mobile phone, a PAD, a laptop computer, a television, or a smart wearable device.

[0082] Unless otherwise defined, the technical terms used in the following examples have the same meanings as those generally understood by those skilled in the art to which the present invention belongs. The experimental reagents used in the following examples, unless otherwise specified, are all conventional biochemical reagents; the raw materials, instruments and equipment used in the following examples, etc., can all be purchased on the market or can be obtained by existing methods; the amounts of the experimental reagents, unless otherwise specified, are the amounts of reagents used in conventional experimental operations; the experimental methods, unless otherwise specified, are all conventional methods.

[0083] The following describes the diaphragm assembly and the sound-generating device of the present invention in detail with specific embodiments and comparative examples. It is worth noting that the following description is only exemplary and does not specifically limit the present invention. Moreover, the comparative examples are selected to reflect the technical progress of the main technical points of the present invention by comparison with the embodiments, and the comparative examples are not all prior art in the field.

[0084] Example 1

[0085] A diaphragm assembly is disclosed, see Figure 1 As shown, the diaphragm assembly 100 includes a diaphragm 110, a dome 120, and an adhesive layer 130 disposed between the diaphragm 110 and the dome 120. The adhesive layer 130 is annular and has a thickness of 30 μm. The diaphragm 110 is made of ethylene acrylate rubber, the dome 120 is made of aluminum composite material, the adhesive layer 130 is a modified polystyrene-poly (ethylene-butylene)-polystyrene block copolymer / PP / PPO blend system, the mass percentage of PP and PPO in the total mass of the adhesive layer is 8%, and the modified polystyrene-poly (ethylene-butylene)-polystyrene block copolymer is obtained by grafting polystyrene-poly (ethylene-butylene)-polystyrene block copolymer (SEBS) with glycidyl methacrylate.

[0086] The process of bonding the diaphragm 110 and the dome 120 via the bonding layer 130 is as follows: firstly bonding one side of the bonding layer 130 to the dome 120 , and then hot pressing the other side of the bonding layer 130 to the diaphragm 110 at 180° C. for 20 seconds.

[0087] Example 2

[0088] The remaining operations are the same as those in Example 1, except that the mass percentage of the blended system is different from that in Example 1, and the mass percentage of PP and PPO in the total mass of the bonding layer is 5% in total.

[0089] Example 3

[0090] The remaining operations are the same as those in Example 1, except that a modified polystyrene-poly(ethylene-butylene)-polystyrene block copolymer / PAR blend system is used, the mass percentage of RAR in the total mass of the adhesive layer is 5%, and the modified polystyrene-poly(ethylene-butylene)-polystyrene block copolymer is obtained by grafting polystyrene-poly(ethylene-butylene)-polystyrene block copolymer (SEBS) with glycidyl methacrylate.

[0091] Comparative Example 1

[0092] The remaining operations are the same as those in Example 1, except that the adhesive layer 130 is an epoxy-modified polystyrene-poly(ethylene-butylene)-polystyrene block copolymer. The epoxy-modified polystyrene-poly(ethylene-butylene)-polystyrene block copolymer is obtained by grafting polystyrene-poly(ethylene-butylene)-polystyrene block copolymer (SEBS) with glycidyl methacrylate.

[0093] Comparative Example 2

[0094] The remaining operations are the same as those in Example 1, except that the adhesive layer 130 is a polyacrylate pressure-sensitive adhesive.

[0095] Ejection force test.

[0096] Ejection force test method:

[0097] a) Use tooling to fix the diaphragm assembly;

[0098] b) Install the top head under the dynamometer, and place the diaphragm assembly and the top head of the dynamometer vertically;

[0099] c) Run the dynamometer with the ejector head in vertical contact with the ball top until the diaphragm separates from the ball top or the diaphragm is damaged. Record the force value of the dynamometer, which is the ejection force value.

[0100] Modulus of elasticity.

[0101] Elastic modulus test method: refer to standard GB / T 33061.10-2016 and use rheometer for testing.

[0102] The rheometer can record the stress changes under different strains to obtain a stress-strain curve. There is usually a linear part on the stress-strain curve, which is the linear elastic region of the material. The elastic modulus of the bonding layer can be obtained through this linear part.

[0103] The test results are shown in Table 1.

[0104] Table 1 Summary of adhesive layer properties in the examples and comparative examples

[0105]

[0106] It can be found from Table 1 that under the conditions of the same bonding area and equal bonding thickness, the blending system of the reinforcing resin and the modified polystyrene-poly(ethylene-butylene)-polystyrene block copolymer in the embodiment does not affect the bonding force, and the performance of the bonding layer does not change, but can significantly improve the elastic modulus of SEBS and the bonding layer at high temperature, and enhance the high temperature resistance effect. At the same time, the shrinkage rate of the bonding layer thickness, the elastic modulus at 25°C, and the ejection force at 25°C in the embodiment of the present invention are better than those in the comparative example. The elastic modulus of the diaphragm assembly at 120°C in Example 1 is 2MPa, the elastic modulus of the diaphragm assembly at 120°C in Example 2 is 1.5MPa, and the elastic modulus of the diaphragm assembly at 120°C in Example 3 is 1.7MPa, which are significantly higher than the elastic modulus of the diaphragm assembly in Comparative Example 1 and Comparative Example 2 under the same conditions of 0.5MPa and 0.04MPa. The high-temperature modulus of the bonding layer is significantly improved, and it can be used in a high-temperature environment for a long time.

[0107] Acoustic performance test comparison

[0108] In the present invention, the diaphragm assemblies in Example 1 and Comparative Example 2 are respectively assembled into micro-speakers of the same structure and model, and the reliability acoustic performance test of the products is carried out by sweeping frequency vibration for 48 hours at a voltage of 3V in an environment of 65°C and 95% humidity.

[0109] like Figure 3 As shown, through the total harmonic distortion curves of the speakers corresponding to Example 1 and Comparative Example 2, it can be seen that Comparative Example 2 has distortion, while the example has no problem. The product was disassembled and it was found that the bonding layer of Comparative Example 2 had cracking. This once again proves that the blending system in the present invention increases the high-temperature elastic modulus of the bonding layer, thereby ensuring the bonding strength and performance, so that the diaphragm assembly can be used in a high-temperature environment for a long time, meeting the needs of acoustic products.

[0110] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A diaphragm assembly, characterized in that: The invention comprises a diaphragm, a dome and an adhesive layer disposed between the diaphragm and the dome, wherein the adhesive layer is a blended system, the blended system comprises a reinforcing resin and a modified polystyrene-poly(ethylene-butylene)-polystyrene block copolymer, the mass percentage of the reinforcing resin in the total mass of the adhesive layer is 0.5% to 60%, At 25° C., the elastic modulus of the adhesive layer is 20 MPa to 800 MPa; and / or, at 120° C., the elastic modulus of the adhesive layer is 0.05 MPa to 5 MPa.

2. The diaphragm assembly according to claim 1, characterized in that: The mass percentage of the reinforcing resin in the bonding layer is 1% to 10%; Preferably, at 120° C., the elastic modulus of the bonding layer is 1 MPa to 2 MPa.

3. The diaphragm assembly according to claim 1, characterized in that: At 25°C, the ejection force per unit area of ​​the diaphragm assembly is 4N to 30N; Preferably, at 25° C., the ejection force per unit area of ​​the diaphragm assembly is 10N to 30N.

4. The diaphragm assembly according to claim 1, characterized in that: The bonding temperature of the diaphragm and the dome through the bonding layer is 100° C. to 200° C., and the bonding time is 5s to 60s; Preferably, the bonding temperature of the diaphragm and the dome through the bonding layer is 150° C. to 180° C.

5. The diaphragm assembly according to claim 1, characterized in that: After being treated at 120° C. for 3 hours, the thickness shrinkage rate of the adhesive layer is ≤3%; Preferably, after being treated at 120° C. for 3 hours, the thickness shrinkage rate of the adhesive layer is ≤1%; Preferably, the thickness of the adhesive layer is 10 μm to 100 μm; Preferably, the thickness of the diaphragm assembly is 60 μm to 300 μm.

6. The diaphragm assembly according to claim 1, characterized in that: The modified polystyrene-poly(ethylene-butylene)-polystyrene block copolymer contains a benzene ring and a functional group, and the functional group includes at least one of an epoxy group, a styrene group, an ester group, and an acid anhydride; Preferably, the molar ratio of the functionalized group to the benzene ring in the modified polystyrene-poly(ethylene-butylene)-polystyrene block copolymer is (0.05-5):100; Preferably, the modified polystyrene-poly(ethylene-butylene)-polystyrene block copolymer is obtained by grafting a polystyrene-poly(ethylene-butylene)-polystyrene block copolymer with an active compound containing a functional group; Preferably, the active compound containing a functional group is selected from at least one of glycidyl methacrylate, 1,2-epoxy-4-vinylcyclohexane, 2,3-epoxypropyltrimethylammonium chloride, polystyrene and maleic anhydride.

7. The diaphragm assembly according to claim 1, characterized in that: The reinforcing resin is selected from at least one of polyethylene, polypropylene, polyphenylene ether, polycarbonate, polyetheretherketone, polyarylate, polystyrene, thermoplastic polyester elastomer, thermoplastic polyurethane elastomer rubber, and nylon elastomer.

8. The diaphragm assembly according to claim 1, characterized in that: The material of the diaphragm is selected from at least one of engineering plastics and elastomeric materials; and / or, The material of the dome is selected from at least one of carbon fiber, aluminum metal, aluminum-based composite materials and engineering plastics.

9. A sound-generating device, characterized in that: Comprising the diaphragm assembly described in any one of claims 1-8.

10. An electronic device, characterized in that: Includes the sound-generating device as claimed in claim 9.

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