Shell of sound production device, sound production device and electronic equipment

Abstract

The invention discloses a shell of a sound production device, the sound production device and electronic equipment. The shell comprises a first shell body and a second shell body, the first shell body and the second shell body are each provided with a welding part, the welding part of the first shell body and the welding part of the second shell body are connected in an ultrasonic welding mode, the welding parts are formed by injection molding of a composite material composed of carbon fibers and alloy materials, the mass ratio of the carbon fibers to the alloy materials is 0.10-0.65, and the mass ratio of the carbon fibers to the alloy materials is 0.10-0.65. The alloy material comprises a first component and a second component, the first component is polyphenyl ether, the second component is at least one of polystyrene, polyamide, ABS and PBT, the mass ratio of the second component to the first component is 0.05-0.45, and the melting enthalpy of the alloy material is smaller than or equal to 10 J / g. According to the invention, the welding part is formed by injection molding of a composite material containing carbon fibers and an alloy material. The alloy material comprises a non-crystalline structure, and ultrasonic welding is easier to weld, so that the welding firmness and air tightness between the first shell and the second shell can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of electroacoustic conversion, and more specifically, to a shell of a sound-generating device, a sound-generating device and an electronic device. Background Art

[0002] The sound module generally includes a module shell and a sound unit disposed in the module shell. The module shell includes a module upper shell and a module lower shell. The sound unit cooperates with the module shell to define a front sound cavity and a rear sound cavity. The module shell is provided with a sound outlet hole connected to the front sound cavity. The module shell is made of metal material and / or plastic material.

[0003] In the related art, a module shell made of a composite of PPA (polyphthalamide) + fiber material is proposed. The module shell has a high structural strength and meets the use requirements of the sound module. When the sound module is assembled, the upper shell of the module is connected to the lower shell of the module by ultrasonic welding. However, due to the high melting enthalpy of the PA66 material, the welding strength of the upper shell of the module and the lower shell of the module is low when ultrasonically welding, there are a large number of cold welds, and the air tightness of the shell is poor; and the density of the material used to prepare the module shell is relatively high, resulting in a large mass of the shell, which does not meet the lightweight design requirements of the sound module.

[0004] Therefore, it is necessary to provide a new technical solution to solve the above technical problems. Summary of the invention

[0005] An object of the present invention is to provide a new technical solution for a housing of a sound-generating device.

[0006] According to a first aspect of the present invention, a shell of a sound-generating device is provided. The shell includes a first shell and a second shell, the first shell and the second shell are both provided with a welding portion, the welding portion of the first shell and the welding portion of the second shell are ultrasonically welded, and the welding portion is formed by injection molding of a composite material composed of carbon fiber and an alloy material, wherein the mass ratio of the carbon fiber to the alloy material is 0.10-0.65, the alloy material includes a first component and a second component, the first component is polyphenylene ether, the second component is at least one of polystyrene, polyamide, ABS, and PBT, the mass ratio of the second component to the first component is 0.05-0.45, and the melting enthalpy of the alloy material is ≤10J / g.

[0007] Optionally, the glass transition temperature of the alloy material is ≥110°C.

[0008] Optionally, the composite material further comprises hollow glass microspheres, and the distribution density of the hollow glass microspheres in the polyamide composite material is 0.1 g / cm 3 -0.8g / cm 3 .

[0009] Optionally, the carbon content of the carbon fiber is 90%-99.99%, and / or the graphitization degree R of the carbon fiber is 0.85-1.15, and / or the length of the carbon fiber is 0.1mm-1mm.

[0010] Optionally, the carbon fiber is sizing treated with a sizing agent, and the sizing agent includes at least one of a polystyrene sizing agent, a polyamide sizing agent, a polyester sizing agent, and an epoxy resin sizing agent.

[0011] Optionally, at least one of the first shell and the second shell is integrally formed as a welded portion; or

[0012] At least one of the first shell and the second shell includes a support portion, and the support portion is integrally injection-molded with the welding portion.

[0013] Optionally, the supporting portion includes a resin material, and the resin material includes at least one of PP, PA610, PA612, PA1010, PA11, PA12, PA1212, PA1012, PA1111, PA1213, PA1313, PPA, PA4T, PA6T, PA9T, PA10T, PA12T, PA46, ABS, PET, PBT, and PC.

[0014] Optionally, the support portion further includes a fiber material, the resin material is mixed with the fiber material, and a mass ratio of the fiber material to the resin material is 0.1 to 0.7.

[0015] Optionally, the density of the shell is 0.9 g / cm 3 -1.3g / cm 3 ;

[0016] And / or, more than 20% of the area of ​​the shell has a thickness of ≤0.3 mm.

[0017] Optionally, the bending modulus of the shell is 5GPa-35GPa;

[0018] And / or, the bending strength of the shell is 50MPa-350Mpa;

[0019] And / or the heat deformation temperature of the shell is ≥110°C.

[0020] Optionally, the waterproof rating of the housing is not less than 1ATM.

[0021] According to a second aspect of the present invention, a sound-generating device is provided, which includes a housing of the sound-generating device described in the present invention.

[0022] According to a third aspect of the present invention, an electronic device is provided, which includes the sound generating device of the present invention.

[0023] In an embodiment of the present invention, the welding part of the first shell and the second shell is formed by injection molding of a composite material comprising carbon fiber and an alloy material. The alloy material includes a first component and a second component, the first component is polyphenylene ether, and the second component is at least one of polystyrene, polyamide, ABS, and PBT. The alloy material includes a non-crystalline structure, so the heat required for melting the welding interface of the two welding parts is lower, the energy required for ultrasonic welding is lower, and it is easier to weld, thereby improving the welding firmness and airtightness between the first shell and the second shell. Moreover, since the alloy material has no crystalline structure and has the characteristic of low density, a lightweight design of the shell can be achieved. Moreover, the above-mentioned composite material also includes a carbon fiber material, which has a higher modulus and strength, thereby improving the structural strength of the shell.

[0024] Further features and advantages of the present invention will become apparent from the following detailed description of exemplary embodiments of the present invention with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

[0026] Figure 1 is an exploded view of a sound generating device according to an embodiment of the present invention.

[0027] Figure 2 is a cross-sectional view of a sound generating device according to an embodiment of the present invention.

[0028] Figure 3 is a cross-sectional view of another sound-generating device according to an embodiment of the present invention.

[0029] Figure 4 3 are frequency response curves of the sound-generating devices according to Examples 1 and 4 of the present invention and Comparative Example 3.

[0030] Description of reference numerals:

[0031] 10. First shell; 111. Front sound cavity; 121. Rear sound cavity; 15. Welding part; 16. Support part; 20. Sound unit; 30. PCB; 40. Second shell. DETAILED DESCRIPTION

[0032] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention unless otherwise specifically stated.

[0033] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

[0034] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0035] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0036] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0037] According to the first embodiment of the present invention, a shell of a sound-generating device is provided. The shell includes a first shell 10 and a second shell 40, wherein the first shell 10 and the second shell 40 are both provided with a welding portion 15, wherein the welding portion 15 of the first shell 10 and the welding portion 15 of the second shell 40 are connected by ultrasonic welding, wherein the welding portion 15 is formed by injection molding of a composite material composed of carbon fiber and an alloy material, wherein the mass ratio of the carbon fiber to the alloy material is 0.10-0.65, wherein the alloy material includes a first component and a second component, wherein the first component is polyphenylene ether, and the second component is at least one of polystyrene, polyamide, ABS, and PBT, wherein the mass ratio of the second component to the first component is 0.05-0.45, and the melting enthalpy of the alloy material is ≤10 J / g.

[0038] Specifically, Figure 1-Figure 3 As shown, in a specific embodiment of the present invention, the first shell 10 and the second shell 40 are connected together to form a accommodating cavity therein. The accommodating cavity is used to accommodate the sound unit 20 and the PCB 30. The sound unit 20 is connected to the PCB 30. The PCB 30 is connected to the external circuit. A welding portion 15 is provided at the edge of the first shell 10 and the second shell 40. The welding portion 15 is formed by injection molding of a composite material including carbon fiber and an alloy material. When connecting, the two welding portions 15 are arranged opposite to each other, and the two welding portions 15 are melted by ultrasonic welding, and the two welding portions 15 are bonded to each other. After curing, the two welding portions 15 are connected together.

[0039] In this embodiment, the composite material includes carbon fiber and alloy material mixed together. The alloy material is formed by blending a plurality of polymers. The alloy material can have the advantages of a plurality of polymers, such as low melting temperature, high strength, high modulus, low density, etc. The alloy material of the present invention includes a first component and a second component. The first component is polyphenylene ether. The second component is at least one of polystyrene, polyamide, ABS, and PBT. In other words, the alloy material is formed by blending a mixture of polyphenylene ether and one or more of the second components. The polyphenylene ether, ABS, and polystyrene in the alloy material are all amorphous materials, so that the alloy material includes a non-crystalline structure, and there is no phase interface between the amorphous component and the crystalline component in the non-crystalline structure, wherein the phase interface causes the dissipation of welding energy during welding, resulting in poor welding, such as cold welding, poor air tightness, and the like. Moreover, the material fluidity of polystyrene, polyamide, ABS, and PBT in the second component is good, thereby improving the fluidity of the alloy material and realizing injection molding of the composite material. It should be noted that although polyamide and PBT in the second component are crystalline materials, the second component accounts for a small proportion in the alloy material, and the second component mainly contributes to the fluidity of the alloy material, so it will not affect the ultrasonic welding effect of the weld. When polystyrene is selected as the second component, the alloy material is entirely composed of amorphous materials, and the ultrasonic welding effect of the weld is better.

[0040] In the present invention, the composite material includes an alloy material including an amorphous structure, and the amorphous structure does not have a phase interface between an amorphous component and a crystalline component, so the ultrasonic vibration energy can be well transmitted in the material during the ultrasonic welding process, which is conducive to transmitting the ultrasonic vibration energy to the two welding parts 15, and the two welding parts 15 are more easily melted, which effectively improves the firmness of the welding of the first shell 10 and the second shell 40. Since the alloy material has no crystalline structure, the heat required for melting the welding interface of the two welding parts 15 is lower, the energy required for ultrasonic welding is lower, and it is easier to weld, thereby improving the welding strength between the first shell 10 and the second shell 40. In addition, the welding consistency of each part of the welding part 15 is good, and it is not easy to form defects such as cold welding and poor air tightness, which can improve the welding air tightness between the first shell 10 and the second shell 40 and improve the waterproof effect of the shell. In addition, since the alloy material includes an amorphous structure, it has the characteristics of low density, which is conducive to realizing the lightweight design of the shell.

[0041] Among them, polyphenylene ether is a polymer polymerized by 2,6-dimethylbenzene through an oxidative coupling method. Polyphenylene ether has excellent water vapor resistance and dimensional stability, but polyphenylene ether has poor melt fluidity and is difficult to mold. Polystyrene is a polymer synthesized from styrene monomers through free radical addition polymerization. Polystyrene is a colorless and transparent thermoplastic. The glass transition temperature of polystyrene is relatively high, for example, higher than 100°C, and it has very high fluidity. When polystyrene and polyphenylene ether are mixed together to form an alloy material, it can have the advantages of both polystyrene and polyphenylene ether. Polyphenylene ether can improve the dimensional stability of the weld, and polystyrene can effectively improve the fluidity of polyphenylene ether, which can meet the process requirements of injection molding, and the molding effect of the alloy material is good.

[0042] Polyamide is also called nylon. Polyamide is a general term for thermoplastic resins containing repeated amide groups (-NHCO-) ​​on the main chain of the molecule. Polyamide materials have the characteristics of good fluidity. When polyamide and polyphenylene ether are blended to form an alloy material, polyamide can improve the fluidity of polyphenylene ether, and the alloy material has good heat resistance, rigidity, toughness and dimensional stability.

[0043] ABS is a terpolymer of acrylonitrile, butadiene and styrene. The relative content of the three monomers can be selected according to actual needs. ABS has the common properties of the three monomers. Acrylonitrile makes ABS have good chemical corrosion resistance and heat resistance, and has a certain surface hardness. Butadiene makes ABS have high elasticity and toughness. Styrene makes ABS have the processing and molding characteristics of thermoplastics. When polyphenylene ether and ABS are blended to form an alloy material, the alloy material has good impact resistance, processing fluidity and surface gloss.

[0044] PBT is a polyester made by polycondensation of terephthalic acid and 1,4-butanediol. PBT has excellent fluidity and toughness. When PBT is blended with polyphenylene ether to form an alloy material, PBT can improve the fluidity of polyphenylene ether, and the alloy material has good fluidity and toughness.

[0045] Of course, the alloy material can also be an alloy material formed by blending polyphenylene ether with two, three or four of polystyrene, polyamide, ABS and PBT. The alloy material can have good fluidity, heat resistance, strength and modulus.

[0046] In addition, when the mass ratio of the second component to the first component is less than 0.05, the second component has a small improvement in the fluidity of the polyphenylene ether and cannot meet the injection molding requirements; when the mass ratio of the second component to the first component is greater than 0.45, the melting temperature of the alloy material is too high, causing the welding portion 15 to be prone to defects such as cold welding and loose welding. In this embodiment, the mass ratio of the second component to the first component is 0.05-0.45, which makes the alloy material have both good fluidity and low melting temperature, and the welding effect of the first shell 10 and the second shell 40 is good. Optionally, the mass ratio of the second component to the first component can be 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, etc.

[0047] Carbon fiber is a high-performance fiber material with high strength and high modulus, which is made from organic fibers (such as polyacrylonitrile, viscose fiber or asphalt) through carbonization and other processes. The density of carbon fiber is lower than that of glass fiber, and the carbon fiber reinforced shell structure strength effect is better. Under the condition of meeting the shell strength and modulus requirements, the amount of carbon fiber added to the composite material is lower, which is conducive to achieving lightweight shell.

[0048] In addition, the mass ratio of the carbon fiber to the alloy material is 0.10-0.65. When the mass ratio of the carbon fiber to the alloy material is greater than 0.65, due to the high distribution density of the carbon fiber in the composite material, the alloy material at the welding interface of the welding portion 15 is relatively small, resulting in poor welding defects such as cold welding at the welding interface, and the welding strength and welding yield are reduced. As the mass ratio of the carbon fiber to the alloy material continues to increase, the melting index of the composite material decreases, the viscosity of the melt increases, and the glue injection becomes difficult, resulting in an increase in the proportion of products with glue shortage. The ultrasonic welding strength and welding yield of the welding portion 15 of the first shell 10 and the second shell 40 will be significantly reduced. On the contrary, when the mass ratio of the carbon fiber to the alloy material is less than 0.10, the reinforcing effect of the carbon fiber on the strength and modulus of the composite material is poor. During the reliability verification process of the sound-generating device, the shell is prone to resonance between the shell and the sound-generating monomer 20 in the intermediate frequency stage, resulting in excessive distortion of the intermediate frequency THD of the sound-generating device. When the mass ratio of the carbon fiber to the alloy material is 0.10-0.65, the melting temperature of the composite material is low, making ultrasonic welding easier, the welding of the two welding parts 15 is firm, and the strength and modulus of the shell are high, the amount of carbon fiber added is small, the shell is light, and the product yield is high. Optionally, the mass ratio of the carbon fiber to the alloy material is 0.10, 0.15, 0.20, 0.25, 0.3, 0.35, 0.4, 0.45, 0.46, 0.50, 0.55, 0.60, 0.65, etc. The above values ​​can all make the melting temperature of the composite material low, ultrasonic welding easy, the overall structural strength of the formed shell is high, and the modulus and strength of the composite material are high.

[0049] The melting enthalpy is a physical quantity that characterizes the amount of heat consumed by a substance during the melting process. Specifically, the melting enthalpy is the amount of heat absorbed at constant temperature and pressure when a substance changes from a solid state to a liquid state. The greater the melting enthalpy of the alloy material, the higher the energy consumed when melting. In this embodiment, the melting enthalpy of the alloy material is ≤10J / g. Within this range, the composite material consumes less energy during ultrasonic welding, and the melting of the composite material is easier. Optionally, the melting enthalpy of the alloy material is 2J / g, 3J / g, 4J / g, 5J / g, 6J / g, 7J / g, 8J / g, 9J / g, 10J / g, etc. The above values ​​all consume less energy during ultrasonic welding of the composite material, and the melting of the composite material is easier. It should be noted that the melting enthalpy of the alloy material can be tested according to the GBT19466.3-2004 standard.

[0050] The preparation process of the shell of the present invention may include:

[0051] (1) Preparation of composite materials. Polyphenylene ether and the second component are added to a twin-screw extruder from the main feed port according to a set mass ratio for melting. After the two materials are melted, carbon fiber is added from the side feed port. The carbon fiber and the mixed alloy material are sheared and mixed uniformly in the extruder, and then extruded into granules.

[0052] (2) Preparation of the shell. The granulated composite material is melted again during injection molding and then injected into a mold to form the first shell 10 and the second shell 40;

[0053] Alternatively, during injection molding, the support portion 16 is firstly formed by injection molding in a mold, and then the welding portion 15 is formed by injection molding at the edge of the support portion 16 , thereby forming the first shell 10 and the second shell 40 .

[0054] (3) Assemble the sound unit 20 and PCB 30 and other components into the accommodation cavity formed by the first shell 10 and the second shell 40. Then, align the two welding parts 15 of the first shell 10 and the second shell 40, and perform ultrasonic welding to connect the two welding parts 15 together.

[0055] It should be noted that the length-to-diameter ratio of carbon fiber is relatively large, and its ability to resist shear is not high, so it is usually necessary to add carbon fiber after the alloy material is melted. This can effectively reduce the damage of the carbon fiber during the mixing process, thereby enhancing the reinforcement effect of carbon fiber on the composite material.

[0056] In an embodiment of the present invention, the welding portion 15 of the first shell 10 and the second shell 40 is formed by injection molding of a composite material comprising carbon fiber and an alloy material. The alloy material comprises a first component and a second component, the first component being polyphenylene ether, and the second component being at least one of polystyrene, polyamide, ABS, and PBT. Both polyphenylene ether and polystyrene in the alloy material are amorphous materials, so the alloy material contains a large amount of non-crystalline structures, so the heat required for melting the welding interface of the two welding portions is lower, the energy required for ultrasonic welding is lower, and welding is easier, thereby improving the welding firmness and airtightness between the first shell 10 and the second shell 40. Moreover, since the alloy material comprises a large amount of non-crystalline structures and has the characteristic of low density, a lightweight design of the shell can be achieved. Moreover, the composite material comprises a carbon fiber material, which has a high modulus and strength, thereby improving the structural strength of the shell.

[0057] In a specific embodiment of the present invention, the glass transition temperature of the alloy material is ≥110°C.

[0058] The glass transition temperature refers to the temperature at which an amorphous substance transitions between a glassy state and a highly elastic state. When the glass transition temperature is lower than the glass transition temperature, the material is in a glassy state with high strength and modulus; when the glass transition temperature is reached or higher than the glass transition temperature, the material is in a highly elastic state with strong elasticity. When the glass transition temperature is less than 110°C, the composite material is easily deformed at a higher operating temperature, resulting in low structural strength of the first shell 10 and the second shell 40, and poor high temperature resistance of the shell. In this embodiment, the glass transition temperature of the alloy material is ≥110°C. This makes the connection strength of the first shell 10 and the second shell 40 high at a higher operating temperature, and the high temperature resistance of the shell as a whole is excellent. During the high temperature reliability test, the structural strength is high, the modulus and strength of the shell decrease little, and the performance stability is excellent. Optionally, the glass transition temperature of the alloy material is 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, etc. The above values ​​all make the connection strength of the first shell 10 and the second shell 40 high, the high temperature resistance of the shell as a whole is excellent, and the structural strength is high. It should be noted that the glass transition temperature can be tested according to GB / T19466.2-1999 standard.

[0059] In a specific embodiment of the present invention, the composite material further comprises hollow glass microspheres, and the distribution density of the hollow glass microspheres in the composite material is 0.1 g / cm 3 -0.8g / cm 3 .

[0060] In this embodiment, the composite material also includes hollow glass microspheres. For example, when preparing the composite material, hollow glass microspheres and carbon fibers are added to the alloy material melt; after mixing, a composite material is finally formed. Since hollow glass microspheres may be shear-damaged during the mixing process, the hollow glass microspheres are added after the carbon fibers are added to minimize the shear damage of the hollow glass microspheres during the mixing process. Hollow glass microspheres can significantly reduce the density of the composite material and meet the demand for lightweight shells.

[0061] Wherein, the mass percentage of the hollow glass microspheres is 1%-20%. It should be noted that when the mass percentage of the hollow glass microspheres in the composite material is less than 1%, the effect of reducing the density of the composite material is not obvious; on the contrary, when the mass percentage of the hollow glass microspheres in the composite material is greater than 20%, the impact resistance of the composite material will decrease, and the shell will be easily damaged in the drop reliability test of the sound-generating device. In this embodiment, the mass percentage of the hollow glass microspheres is 1%-20%. Within this range, the density of the composite material can be effectively reduced, and the connection strength of the two welding parts 15 is high, and the shell is not easy to be damaged. Optionally, the mass percentage of the hollow glass microspheres is 1%, 2%, 4%, 6%, 9%, 10%, 12%, 13%, 14%, 16%, 17%, 18%, 19%, 20%. The above values ​​can effectively reduce the density of the composite material, and the connection strength of the two welding parts 15 is high, and the shell is not easy to be damaged.

[0062] The distribution density of hollow glass microspheres in composite materials refers to the mass of hollow glass microspheres per unit volume of the composite material. The distribution density of hollow glass microspheres is less than 0.1g / cm 3 When the density of the review material is reduced, the effect is not obvious; on the contrary, the distribution density of the hollow glass microspheres is greater than 0.8g / cm 3 When the composite material is subjected to the impact test, the impact resistance of the composite material will be reduced. In the drop reliability test of the sound-generating device, the shell is easily damaged. In this embodiment, the distribution density of the hollow glass microspheres in the composite material is 0.1 g / cm 3 -0.8 / cm 3 Within this range, the density of the composite material can be effectively reduced, and the connection strength of the two welding parts 15 is high, and the shell is not easily damaged. Optionally, the distribution density of the hollow glass microspheres in the composite material is 0.1 g / cm 3 , 0.2g / cm 3 , 0.3g / cm 3 , 0.4g / cm 3 , 0.45g / cm 3 , 0.5g / cm 3 , 0.6g / cm 3, 0.7g / cm 3 , 0.8g / cm 3 The above values ​​can effectively reduce the density of the composite material and increase the connection strength of the two welding portions 15, so that the shell is not easily damaged.

[0063] In a specific embodiment of the present invention, the carbon content of the carbon fiber is 90%-99.99%.

[0064] And / or, the graphitization degree R of the carbon fiber is 0.85-1.15,

[0065] And / or, the length of the carbon fiber is 0.1 mm-1 mm.

[0066] Specifically, the lower the carbon content of the carbon fiber, the lower the modulus of the carbon fiber; conversely, the higher the carbon content of the carbon fiber, the higher the modulus of the carbon fiber. In this embodiment, the carbon content of the carbon fiber is 90%-99.99%. Within the range, under the same mass content conditions, the modulus of the composite material is high and the overall structural strength of the shell is high. Optionally, the carbon content of the carbon fiber is 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99.99%, etc. The above values ​​can all make the modulus of the composite material high and the overall structural strength of the shell high.

[0067] The graphitization degree R value refers to the value of 1360cm when the Raman spectrum is used to test the carbon fiber. -1 The peak intensity of 1583cm -1 The ratio of peak intensity. The degree of graphitization is inversely proportional to the R value. The smaller the R value, the higher the degree of graphitization, the higher the degree of graphitization of the carbon fiber, the higher the modulus along the fiber direction, and the higher the effect of improving the modulus of the composite material. When the R value is greater than 1.15, the graphitization degree of the carbon fiber is too small, and the modulus improvement effect on the composite material is poor. When the R value is less than 0.85, the degree of graphitization of the carbon fiber is high, and the raw material requirements and processing requirements for the carbon fiber are both high, which increases the cost. In this embodiment, the graphitization degree R value of the carbon fiber is 0.85-1.15. Within this range, the modulus of the composite material is high and the cost of the carbon fiber is low, and the cost of the composite material is low. Optionally, the graphitization degree R value of the carbon fiber is 0.85, 0.9, 0.95, 1, 1.05, 1.1, 1.15. The above values ​​can all make the modulus of the composite material high and the cost low.

[0068] In addition, the length of the carbon fiber is 0.1mm-1mm. When the length of the carbon fiber is less than 0.1mm, the strength of the shell will decrease at the same carbon fiber content, resulting in damage to the shell in the drop reliability test; when the length of the carbon fiber is greater than 1mm, during the injection molding process, the shell is prone to problems such as exposed fibers and floating fibers, affecting the product yield. In this embodiment, the length of the carbon fiber is 0.1mm-1mm. Within this range, the strength of the shell is high, and the shell is not prone to problems such as exposed fibers and floating fibers during the injection molding process, and the product yield is high. Optionally, the length of the carbon fiber is 0.1mm, 0.2mm, 0.3mm, 0.2mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, etc. The above values ​​can all make the shell strong, and the shell is not prone to problems such as exposed fibers and floating fibers during the injection molding process.

[0069] In a specific embodiment of the present invention, the carbon content of the carbon fiber is 90%-99.99%; the graphitization degree R of the carbon fiber is 0.85-1.15. In this embodiment, the composite material has a high modulus, the overall structural strength of the shell is high and the cost is low.

[0070] In a specific embodiment of the present invention, the graphitization degree R of the carbon fiber is 0.85-1.15; the length of the carbon fiber is 0.1mm-1mm. In this embodiment, the composite material has a high modulus, the overall strength of the shell is high, the cost is low, and the shell is not prone to problems such as exposed fibers and floating fibers during the injection molding process.

[0071] In a specific embodiment of the present invention, the carbon content of the carbon fiber is 90%-99.99%; the length of the carbon fiber is 0.1mm-1mm. In this embodiment, the modulus of the composite material is high, the overall strength of the shell is high, and the shell is not prone to problems such as exposed fibers and floating fibers during the injection molding process.

[0072] In a specific embodiment of the present invention, the carbon content of the carbon fiber is 90%-99.99%; the graphitization degree R of the carbon fiber is 0.85-1.15; and the length of the carbon fiber is 0.1mm-1mm. In this embodiment, the composite material has a high modulus, the overall strength of the shell is high, the cost is low, and the shell is not prone to problems such as exposed fibers and floating fibers during the injection molding process.

[0073] In a specific embodiment of the present invention, the carbon fiber is sizing treated with a sizing agent, and the sizing agent includes at least one of a polystyrene sizing agent, a polyamide sizing agent, a polyester sizing agent, and an epoxy resin sizing agent.

[0074] In this embodiment, the surface of carbon fiber is inert, has poor compatibility with alloy materials, and has low bonding strength. In the composite material preparation process, the surface of carbon fiber needs to be surface treated to improve the compatibility of carbon fiber and long-chain polyamide. Carbon fiber is sizing treated with a sizing agent. The sizing agent includes at least one of a polystyrene sizing agent, a polyamide sizing agent, a polyester sizing agent, and an epoxy resin sizing agent. The above sizing agents can all improve the bonding strength of carbon fiber and alloy materials and improve the compatibility of carbon fiber and alloy materials.

[0075] In a specific embodiment of the present invention, at least one of the first shell 10 and the second shell 40 is integrally formed as a welded portion.

[0076] In other words, in this embodiment, the first shell 10 and / or the second shell 40 are all made of composite material by integral injection molding, the composite material includes alloy material and carbon fiber mixed together, the mass ratio of the carbon fiber to the alloy material is 0.10-0.65, the alloy material includes a first component and a second component, the first component is polyphenylene ether, the second component is at least one of polystyrene, polyamide, ABS, PBT, the mass ratio of the second component to the first component is 0.05-0.45, and the melting enthalpy of the alloy material is ≤10J / g. As mentioned above, the shell has the characteristics of high modulus, high strength, light weight, easy ultrasonic welding, and high welding yield. For example, the first shell 10 is all made of composite material by integral injection molding, and part of the structure of the second shell 40 is made of composite material by integral injection molding; or, part of the structure of the first shell 10 is made of composite material by integral injection molding, and the second shell 40 is all made of composite material by integral injection molding; or, both the first shell 10 and the second shell 40 are all made of composite material by integral injection molding.

[0077] In a specific embodiment of the present invention, at least one of the first shell 10 and the second shell 40 further includes a support portion 16 , and the support portion 16 and the welding portion 15 are integrally injection molded.

[0078] Specifically, if Figure 1-Figure 2As shown, the first shell 10 and / or the second shell 40 are formed by double-shot molding. For example, the support portion 16 is formed in one shot, and the welding portion 15 is formed on the support portion 16 in the second shot. After curing, the support portion 16 and the welding portion 15 are connected together. In this embodiment, the support portion 16 can be processed into a set shape according to actual needs to meet the sound requirements of different sound-emitting devices. The welding portion 15 is formed at the edge of the support portion 16. The welding portion 15 of the first shell 10 and the second shell 40 is used for ultrasonic welding to connect and form the shell. In this setting, different parts of the first shell 10 and / or the second shell 40 are made of different materials according to different functions, and the different materials are molded by integral injection molding. The processing technology of the first shell 10 and / or the second shell 40 is simple and the structural strength is high.

[0079] In a specific embodiment of the present invention, the supporting portion 16 includes a resin material, and the resin material includes at least one of PP, PA610, PA612, PA1010, PA11, PA12, PA1212, PA1012, PA1111, PA1213, PA1313, PPA, PA4T, PA6T, PA9T, PA10T, PA12T, PA46, ABS, PET, PBT, and PC.

[0080] When preparing the support part 16, any one of the above materials can be selected, or at least two of the above materials can be mixed together. The above materials can be processed into a set structure according to the sound generation requirements of the sound generation device.

[0081] In a specific embodiment of the present invention, the support portion 16 further comprises a fiber material, the fiber material comprises carbon fiber and / or glass fiber, the resin material is mixed with the fiber material, and the mass ratio of the fiber material to the resin material is 0.1-0.7.

[0082] In this embodiment, the fiber material is, for example, carbon fiber and / or glass fiber. The resin material and the fiber material are mixed together to form a composite material, and the fiber material can significantly improve the modulus and strength of the composite material. When the mass ratio of the fiber material to the resin material is less than 0.1, the fiber material has a small improvement on the modulus and strength of the composite material; conversely, when the mass ratio of the fiber material to the resin material is greater than 0.7, the density of the composite material formed is large and does not meet the requirements of lightweight shell. In this embodiment, the mass ratio of the fiber material to the resin material is 0.1-0.7. Within the range, the composite material has both high strength and modulus and the mass of the shell formed is light. Optionally, the mass ratio of the fiber material to the resin material is 0.1, 0.15, 0.2, 0.25, 0.3, 0.4, 0.5, 0.6, 0.7, etc., and the above values ​​all make the composite material have both high strength and modulus and the mass of the shell formed is light.

[0083] In a specific embodiment of the present invention, the density of the shell is 0.9 g / cm 3 -1.3g / cm 3 ;

[0084] And / or, at least 10% of the area of ​​the shell has a thickness of ≤0.3 mm.

[0085] Specifically, in this embodiment, due to the low density of the alloy material, the density of the entire shell is 0.9 g / cm 3 -1.3g / cm 3 Within this range, at the same volume, the shell has a smaller mass and sufficient modulus and strength, meeting the requirement of lightweight shell. Optionally, the density of the shell is 0.9g / cm 3 , 1.0g / cm 3 , 1.10g / cm 3 , 1.20g / cm 3 , 1.25g / cm 3 , 1.30g / cm 3 The above values ​​can make the shell light and have sufficient modulus and strength.

[0086] The thickness of at least 10% of the area of ​​the shell is ≤0.3mm. In other words, the thickness of at least 10% of the surface area of ​​the shell is ≤0.3m. For example, the shell includes a top wall and a side wall, and the area with a thickness of ≤0.3m is located on the top wall and / or the side wall; or the shell is a sheet structure, and the area with a thickness of ≤0.3m is located at least partially in the sheet structure. It can be understood that the shell is made of composite material injection molding. Since the composite material has a high modulus and strength, the shell can be made thinner at least partially, thereby increasing the volume of the internal accommodating cavity of the shell, and then increasing the volume of the sound cavity of the sound-emitting device, thereby improving the sound effect of the sound-emitting device.

[0087] In a specific embodiment of the present invention, along the vibration direction of the vibration system of the sound-emitting unit 20, the thickness of at least part of the shell opposite to the sound-emitting unit 20 is ≤0.3mm. This arrangement allows the shell to have a larger space in the vibration direction of the vibration system, allowing the vibration amplitude of the sound-emitting unit 20 to be larger, effectively improving the sound effect. Optionally, the thickness of the shell is 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, etc., and the above values ​​can all make the space inside the shell larger.

[0088] In addition, in order to make the space of the front sound cavity and / or the rear sound cavity larger, the shell of the prior art usually sets a steel sheet in the vibration direction of the vibration system of the shell to reduce the thickness. In the present invention, since the modulus and strength of the composite material are large enough, the part of the shell in the vibration direction of the vibration system can be made thinner, for example, the thickness is ≤0.3mm, thereby increasing the space of the front sound cavity and / or the rear sound cavity. This method does not need to set a steel sheet, and the shell can be integrally formed by injection molding, which makes the preparation process of the shell simpler. Moreover, the shell in the present invention is a uniform overall structure with good structural stability, and there will be no phenomenon that the structural strength and acoustic performance are affected by cracks between the steel sheet and the shell.

[0089] In a specific embodiment of the present invention, the bending modulus of the shell is 5 GPa-35 GPa.

[0090] The bending modulus reflects the ability of a material to resist deformation when subjected to a bending load. If the bending modulus of the shell is too low, for example, less than 5 GPa, the shell is prone to local vibration, which is easy to resonate with the vibration of the sound-emitting monomer 20, resulting in poor sounding effect of the sound-emitting device; if the bending modulus of the shell is too high, for example, greater than 35 GPa, the processing difficulty of the shell will increase and the product yield will decrease. For example, when a shell is prepared using a composite material, it is necessary to increase the amount of carbon fiber added, for example, the mass ratio of carbon fiber to alloy material is greater than 0.65, which will cause the viscosity of the alloy material melt to be too large, and it is easy to expose the fiber and lack of glue during the injection molding process. In this embodiment, the bending modulus of the shell is 5 GPa-35 GPa. Within this range, it can not only avoid the resonance between the shell and the sound-emitting monomer 20, but also reduce the processing difficulty of the shell, reduce shell defects, and improve product yield. Optionally, the bending modulus of the shell is 5 GPa, 10 GPa, 15 GPa, 20 GPa, 25 GPa, 30 GPa, 35 GPa. The above values ​​can avoid resonance between the shell and the sound-emitting unit 20 and reduce the difficulty of processing the shell, thereby improving the product yield.

[0091] In a specific embodiment of the present invention, the bending strength of the shell is 50MPa-350Mpa.

[0092] Bending strength is the maximum normal stress that a material can withstand when it reaches a specified deflection or breaks under a bending load. When the bending strength of the shell is lower than 50MPa, the shell is prone to deformation or even fracture when impacted; when the bending strength is higher than 350MPa, the shell has poor fluidity during injection molding and is difficult to process. In this embodiment, the bending strength of the shell is 50MPa-350Mpa. Within this range, the shell is not easily deformed when impacted, and the shell has low processing difficulty and high product yield. Optionally, the bending strength of the shell is 50MPa, 100MPa, 200MPa, 300MPa, 350Mpa, etc. The above values ​​all make the shell have excellent impact resistance and low processing difficulty, and high product yield.

[0093] In a specific embodiment of the present invention, the thermal deformation temperature of the shell is ≥110°C.

[0094] The heat deformation temperature reflects the ability of the material to resist deformation under heat and load conditions. The higher the heat deformation temperature of the shell, the more it indicates that the shell can maintain structural stability under higher conditions. In this embodiment, the heat deformation temperature of the shell is ≥110°C, so that the shell has strong high temperature resistance and is not easy to deform during high temperature and high humidity reliability and high power reliability verification. Optionally, the heat deformation temperature of the shell is 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C, 200°C, etc. The above values ​​all make the shell have strong high temperature resistance and is not easy to deform during high temperature and high humidity reliability and high power reliability verification.

[0095] In a specific embodiment of the present invention, the bending modulus of the shell is 5GPa-35Gpa; and / or, the bending strength of the shell is 50MPa-350Mpa; and / or, the thermal deformation temperature of the shell is ≥110°C. In other words, the performance of the shell at least meets the above two conditions. This significantly improves the shell's anti-deformation ability and high temperature resistance and reduces processing difficulty.

[0096] In a specific embodiment of the present invention, the waterproof rating of the housing is at least 1 ATM.

[0097] In this embodiment, the welding portion 15 of the first shell 10 and the welding portion 15 of the second shell 40 are connected by ultrasonic welding, and the welding portion 15 is formed by injection molding of a composite material, the composite material includes carbon fiber and alloy material mixed together, the alloy material includes a first component and a second component, the first component is polyphenylene ether, the second component is at least one of polystyrene, polyamide, ABS, and PBT, the mass ratio of the second component to the first component is 0.05-0.45, and the melting enthalpy of the alloy material is ≤10J / g. In this embodiment, due to the low melting temperature of the alloy material, the heat required for melting of the welding interface of the two welding portions 15 is lower, the energy of ultrasonic welding can be lower, it is easier to weld, and it is not easy to have problems such as cold welding and air gap. In addition, the mass ratio of the carbon fiber to the alloy material is 0.10-0.65, so that the strength and modulus of the welding portion 15 are significantly improved. In the above manner, the shell will not deform or leak at a water pressure of at least 10 meters.

[0098] According to a second embodiment of the present invention, a sound-generating device is provided, which includes the housing of the sound-generating device described in the present invention.

[0099] like Figure 1-Figure 3As shown, the sound-emitting device of the present invention includes a shell, a sound-emitting unit 20 and a PCB30. The shell includes a first shell 10 and a second shell 40. The first shell 10 and the second shell 40 are connected together to form a accommodating cavity therein. The accommodating cavity is used to accommodate the sound-emitting unit 20 and at least part of the PCB30. A front sound cavity 111 is formed between the first shell 10 and the sound-emitting unit 20. The front sound cavity 111 has a sound outlet. A rear sound cavity 121 is formed between the second shell 40 and the sound-emitting unit 20. The sound-emitting unit 20 is connected to the PCB30. The PCB30 is connected to an external circuit. The edges of the first shell 10 and the second shell 40 are both provided with welding portions 15. The welding portion 15 is formed by injection molding of a material including carbon fiber and a composite material. The welding portions 15 of the first shell 10 and the second shell 40 are connected together by ultrasonic welding.

[0100] The sound-generating device has the characteristics of high structural strength, good high temperature resistance and good sound-generating effect.

[0101] According to a third embodiment of the present invention, an electronic device is provided. The electronic device includes the sound-generating device of the present invention. The electronic device has the characteristic of good durability. Optionally, the electronic device is a computer, a mobile phone, a watch, a television, a speaker, an AR device, a VR device, etc.

[0102] The shell of the sound-generating device and the sound-generating device according to the embodiment of the present invention are described in detail below in combination with specific embodiments and comparative examples. It is worth noting that the following description is only exemplary and not a specific limitation to the present invention.

[0103] Comparative Example 1

[0104] A shell is formed by injection molding using 70 wt % of PC material and 30 wt % of glass fiber, and the shell is assembled with a sound-generating monomer 20 to obtain a sound-generating device.

[0105] Comparative Example 2

[0106] A shell is formed by injection molding using 75 wt % of PPA material and 25 wt % of glass fiber, and the shell is assembled with a sound-generating monomer 20 to obtain a sound-generating device.

[0107] Comparative Example 3

[0108] A shell is formed by injection molding using 90 wt % of PPA material and 10 wt % of glass fiber, and the shell is assembled with a sound-generating monomer 20 to obtain a sound-generating device.

[0109] Example 1

[0110] A shell is formed by injection molding using 87 wt % of alloy material (wherein the mass ratio of PS to PPO is 0.4) and 13 wt % of carbon fiber, and the obtained shell is assembled with a sound unit 20 to obtain a sound module.

[0111] Example 2

[0112] A shell is formed by injection molding using 80wt% of alloy material (wherein the mass ratio of PS to PPO is 0.4) and 20wt% of carbon fiber, and the obtained shell is assembled with a sound unit 20 to obtain a sound module.

[0113] Example 3

[0114] A shell is formed by injection molding using 70wt% of alloy material (wherein the mass ratio of PS to PPO is 0.4) and 30wt% of carbon fiber, and the obtained shell is assembled with a sound-generating monomer 20 to obtain a sound-generating module.

[0115] Example 4

[0116] A shell is formed by injection molding using 60wt% of alloy material (wherein the mass ratio of PS to PPO is 0.4) and 40wt% of carbon fiber, and the obtained shell is assembled with a sound-generating monomer 20 to obtain a sound-generating module.

[0117] Example 5

[0118] A shell is formed by injection molding using 80wt% of alloy material (wherein the mass ratio of ABS to PPO is 0.2) and 20wt% of carbon fiber, and the shell is assembled with a sound-generating monomer 20 to obtain a sound-generating device.

[0119] Example 6

[0120] A shell is formed by injection molding using 70wt% of alloy material (wherein the mass ratio of PA12 to PPO is 0.45) and 30wt% of carbon fiber, and the shell is assembled with a sound-generating monomer 20 to obtain a sound-generating device.

[0121] Example 7

[0122] A shell is formed by injection molding using 80 wt % of alloy material (wherein the mass ratio of PBT to PPO is 0.15) and 20 wt % of carbon fiber, and the shell is assembled with a sound-generating monomer 20 to obtain a sound-generating device.

[0123] It should be noted that the outer dimensions of the shells in the comparative examples and the embodiments are consistent. For the convenience of comparison, the raw material proportions of comparative examples 1-3 and embodiments 1-7 are shown in Table 1.

[0124] Table 1 - Raw material ratios of the shells of the embodiments and comparative examples

[0125]

[0126]

[0127] The shells of comparative examples 1-3 and the shells of embodiments 1-7 were tested for heat deformation temperature, density, bending modulus, bending strength, melt index and reliability, and the test results are shown in Table 2, Table 3 and Table 4.

[0128] The test conditions and standards are as follows:

[0129] (1) Flexural modulus and flexural strength test: The test is carried out in accordance with GB / T 9341-2008, the standard for determination of flexural properties of plastics.

[0130] (2) Heat deformation temperature test: The test is carried out in accordance with GB / T 1634.2-2004 Plastics - Determination of deformation temperature - Part 2: Plastics, hard rubber and long fiber reinforced composites.

[0131] (3) Density test method: Test in accordance with GB / T 1033.1-2008 Plastics - Determination of density of non-foamed plastics - Part 1: Immersion method, liquid pycnometer method and titration method, using the immersion method.

[0132] (4) Melt index test method: The test is carried out in accordance with GB / T 3682.1-2018 Plastics Thermoplastics - Determination of melt mass flow rate (MFR) and melt volume flow rate (MVR) - Part 1: Standard method.

[0133] (5) High temperature and high humidity reliability test: The sound-generating device is placed in a test environment with a temperature of 85°C and a humidity of 85% for 48 hours, and then the sound-generating device is removed to test its acoustic performance.

[0134] (6) High-power reliability test: The sound-generating device is operated at 1.1 times the rated power for 72 hours, and then its acoustic performance is tested.

[0135] (7) 10-meter waterproof verification test: Place the sound-generating device in water at a depth of 10 meters for 30 minutes, then take it out and test its acoustic performance.

[0136] (8) 2-meter drop reliability test: The sound-generating device is placed at a height of 2 meters and dropped to the ground to cause a collision. The integrity of the shell of the sound-generating device is then observed and its acoustic performance is tested.

[0137] Table 2 - Performance test comparison table of embodiments and comparative examples

[0138] name Heat Deflection Temperature density Flexural modulus Bending Strength Melt index ℃ g / cm3 Gpa mpa g / 10min Comparative Example 1 145 1.43 7.5 162 6 Comparative Example 2 235 1.35 8 190 15 Comparative Example 3 190 1.25 4.4 130 17 Example 1 143 1.17 5.9 135 15 Example 2 145 1.2 11.5 170 14 Example 3 145 1.24 16 195 12 Example 4 145 1.28 21 240 10 Example 5 147 1.21 12 175 13 Example 6 165 1.24 17 190 15 Example 7 185 1.21 11 175 13

[0139] As can be seen from Table 2, the heat deformation temperature of the shell of Examples 1-7 and the heat deformation temperature of the shell of Comparative Examples 1-3 are both ≥120°C. The bending strength of the shell of Examples 1-7 and the bending strength of the shell of Comparative Examples 1-3 are both between 50MPa-350Mpa. The bending modulus of the shell of Examples 1-7 and the bending modulus of the shell of Comparative Examples 1-2 are both between 5GPa-35Gpa. The melt index of the shell of Examples 1-7 and the melt index of the shell of Comparative Examples 2-3 are both ≥10g / 10min. The shell of Comparative Example 1 contains PC material. Due to the high viscosity and poor fluidity of the PC material in the molten state, the melt index of the shell is low and does not meet the requirements of the injection molding process. The glass fiber content in the shell of Comparative Example 3 is low, only 10%, resulting in an unobvious reinforcement effect of the glass fiber on the composite material, resulting in a low bending modulus of the shell.

[0140] In addition, the density of the shells of Examples 1-7 and Comparative Example 3 is ≤1.30 g / cm 3 The density of the shells in Comparative Examples 1-2 is ≥1.35 g / cm 3 , this density does not meet the requirement of lightweight shell.

[0141] It can be seen that the shell of Example 1-7 is formed by injection molding of a composite material composed of carbon fiber and alloy material, wherein the mass ratio of the carbon fiber to the alloy material is 0.10-0.65, the alloy material includes a first component and a second component, the first component is polyphenylene ether, the second component is at least one of polystyrene, polyamide, ABS, and PBT, the mass ratio of the second component to the first component is 0.05-0.45, and the melting enthalpy of the alloy material is ≤10J / g. The alloy material includes a non-crystalline structure, the welding interface is easy to melt, and the ultrasonic welding of the shell is more secure. The heat deformation temperature, bending modulus, and bending strength of the shell of Example 1-7 are all high, indicating that the structural strength of the shell is high, the strength decreases little during high temperature operation, and the structural stability is strong. The density of the shell of Example 1-7 is relatively small, which meets the lightweight requirements of the shell.

[0142] Although some properties of the shells of Examples 1-3, such as the bending modulus, bending strength, and heat deformation temperature of the shell of Example 1, the bending modulus, bending strength, heat deformation temperature, and melt index of the shell of Example 2, and the heat deformation temperature, density, bending strength, and melt index of the shell of Example 3, meet the requirements, the density of the shells of Examples 1-2 is too large and does not meet the requirements of lightweight shells, and the melt index of the shell of Example 1 is relatively low, only 6g / 10min. Due to the low melt index, it is difficult to fill the entire injection mold during the injection molding process, and the shell is short of glue, thereby affecting the product yield. The bending modulus of the shell of Example 3 is low, and the local part of the shell is prone to vibration, which is easy to resonate with the vibration of the sound-emitting monomer 20, resulting in poor sound effect of the sound-emitting device.

[0143] In addition to the above tests, the process performance of the shells of Examples 1-7 and Comparative Examples 1-3 was also tested, as shown in Tables 3 and Figure 4 .

[0144] Table 3 - Comparison of process performance tests of the shells of the embodiment and the comparative example

[0145]

[0146] As can be seen from Table 3, the injection molding yields of the shells of Examples 1-7 and Comparative Examples 2-3 are all high, reaching 100%. The shell of Comparative Example 1 contains PC material, which has high viscosity and poor fluidity in a molten state, making it difficult to fill the entire injection mold during the injection molding process, resulting in a lack of glue in the shell, which results in a low injection molding yield of only 80% for the shell of Comparative Example 1.

[0147] The ultrasonic welding yield of the shells of Examples 1-7 reached 100%. This shows that since the shells of Examples 1-7 are made of composite materials, and the composite materials are made of alloy materials, the melting temperature of the alloy materials is low, making the ultrasonic welding of the first shell 10 and the second shell 40 easier, and it is not easy to form defects such as cold welding and poor air tightness. The shell of Comparative Example 1 is made of amorphous PC and glass fiber composite materials, which have a low melting temperature, so the ultrasonic welding yield is high.

[0148] The shell of Comparative Examples 2-3 uses a composite material of PPA material and glass fiber. PPA material is a crystalline material with a very high melting point of about 300°C. During the ultrasonic welding process, the ultrasonic equipment cannot generate enough heat to fully melt the PPA material, resulting in ultrasonic welding defects, and defects such as cold welding and bubbles are very likely to occur, resulting in a low welding yield of the shell, which cannot meet the waterproof and reliability requirements.

[0149] Table 4 - Comparison of reliability tests of the sound-generating devices of the embodiment and the comparative example

[0150] name High temperature and high humidity reliability High power reliability 10m waterproof verification 2m drop reliability Comparative Example 1 OK OK OK OK Comparative Example 2 OK OK NG NG Comparative Example 3 NG NG NG NG Example 1 OK OK OK OK Example 2 OK OK OK OK Example 3 OK OK OK OK Example 4 OK OK OK OK Example 5 OK OK OK OK Example 6 OK OK OK OK Example 7 OK OK OK OK

[0151] Table 4 is a reliability test comparison table of the embodiments and comparative examples. As can be seen from Table 4, the housings of embodiments 1-7 and the housing of comparative example 1 have passed the tests of high temperature and high humidity reliability, high power reliability, 10m waterproof verification, and 2m drop reliability.

[0152] Since the shell of Comparative Example 2 is made of PPA and glass fiber composite material, PPA material is a crystalline material with a very high melting point of about 300°C. During the ultrasonic welding process, the ultrasonic equipment cannot generate enough heat to fully melt the PPA material, resulting in ultrasonic welding defects, and defects such as cold welding and bubbles are very likely to occur. During the 10m waterproof verification process, the shell of Comparative Example 2 cracked and failed the test; during the 2m drop reliability test, the shell of Comparative Example 2 showed impact cracking and failed the test.

[0153] The shell of Comparative Example 3 adopts a composite material of PPA material and glass fiber. PPA material is a crystalline material with a very high melting point of about 300°C. During the ultrasonic welding process, the ultrasonic equipment cannot generate enough heat to fully melt the PPA material, resulting in ultrasonic welding defects, and defects such as cold welding and bubbles are very likely to occur. During the 10m waterproof verification process, the shell of Comparative Example 3 was cracked and damaged and failed the test; during the 2m drop reliability test, the shell of Comparative Example 3 showed impact cracking and failed the test. In addition, compared with the shell of Comparative Example 2, the mass proportion of PPA material in the shell of Comparative Example 3 is higher, and the mass proportion of glass fiber is lower, which makes the elastic modulus of the shell of Comparative Example 3 smaller and the rigidity of the shell is insufficient. In the high temperature and high humidity reliability test and the high power reliability test, the shell is easy to resonate with the sound monomer and fails the test.

[0154] Figure 4 : are the frequency response curves of the sound-generating devices according to Examples 1 and 4 of the present invention and Comparative Example 3. The horizontal axis is the frequency, in Hz; the vertical axis is the response, in dB; a is the frequency response curve of the sound-generating device of Example 1; b is the frequency response curve of the sound-generating device of Example 4; and c is the frequency response curve of the sound-generating device of Comparative Example 3. Figure 4 It can be seen that the response of curve a and curve b increases with the increase of frequency in the range of 100Hz-1000Hz; after 1000Hz, the response remains above 90dB with the increase of frequency. Curve c basically coincides with curve a and curve b before 10000Hz, but after exceeding 10000Hz, a downward spike appears, which indicates that the rigidity of the shell is insufficient due to the insufficient bending modulus of the shell of comparative example 3, and the shell resonates with the sound-emitting monomer in the high frequency band, resulting in a downward spike in the frequency response curve and distorted sound of the sound-emitting device.

[0155] In summary, the shell of Comparative Example 1 is formed by injection molding of 70wt% PC material and 30wt% glass fiber. Although it can meet the requirements of structural strength, reliability, air tightness and waterproofness, the density of PC material is relatively large, which makes it difficult to meet the lightweight design requirements of the shell, and the melt index of the shell of Comparative Example 1 is low, and it is difficult to fill the entire injection mold during the injection molding process, and the shell is short of glue, which affects the product yield. The shell of Comparative Example 2 is formed by injection molding of 75wt% PPA material and 25wt% glass fiber. Although it can meet the requirements of structural strength, high-power reliability, etc., the density of PPA material is relatively large, which makes it difficult to meet the lightweight design requirements of the shell, and the shell of Comparative Example 2 uses a composite material of PPA material and glass fiber. PPA material is a crystalline material with a very high melting point of about 300°C. During the ultrasonic welding process, the ultrasonic equipment cannot generate enough heat to fully melt the PPA material, resulting in ultrasonic welding defects, and defects such as cold welding and bubbles are very likely to occur, resulting in a low welding yield of the shell. During the 10m waterproof verification and 2m drop reliability test, the shell of Example 2 was cracked and damaged and failed the test. The shell of Example 3 is formed by injection molding of 90wt% PP material and 10wt% glass fiber. Due to the lower mass proportion of glass fiber, the rigidity of the shell of Example 3 is insufficient. In the high temperature and high humidity reliability test and the high power reliability test, the shell is easy to resonate with the sound-emitting monomer, and does not meet the requirements of the high temperature and high humidity reliability test and the high power reliability test. In addition, the shell of Example 3 is made of a composite material of PPA material and glass fiber. PPA material is a crystalline material with a very high melting point of about 300°C. During the ultrasonic welding process, the ultrasonic equipment cannot generate enough heat to fully melt the PPA material, resulting in ultrasonic welding defects. It is very easy to have defects such as cold solder joints and bubbles, resulting in a low welding yield of the shell. During the 10m waterproof verification and 2m drop reliability test, the shell of Example 2 cracked and failed the test.

[0156] The shells of Examples 1-7 are formed by injection molding of alloy materials and carbon fiber materials, and the mass ratio of carbon fiber to the alloy material is 0.10-0.65. Since there is no interface between amorphous components and crystalline components in the alloy material, the ultrasonic vibration energy can be well transmitted in the material during ultrasonic welding, which is conducive to transmitting the ultrasonic vibration energy to the two welding parts 15. The two welding parts 15 are easier to melt, which effectively improves the firmness of the welding of the first shell 10 and the second shell 40. Since the alloy material includes a non-crystalline structure, the heat required for melting the welding interface of the two welding parts 15 is lower, the energy required for ultrasonic welding is lower, and it is easier to weld, thereby improving the welding strength between the first shell 10 and the second shell 40. Moreover, since the alloy material has the characteristic of low density, the density of the shell is 0.9g / cm 3 -1.3g / cm 3 range, so that a lightweight design of the shell can be achieved. The melting temperature of the alloy material is low, which can make the shell have a small drop in strength during high-temperature operation and strong structural stability. Moreover, the above-mentioned composite material includes carbon fiber material, which has a high modulus and strength, thereby improving the structural strength of the shell. In addition, the bending modulus of the shell is in the range of 5GPa-35Gpa, which can not only avoid the resonance between the shell and the sound unit 20, but also reduce the processing difficulty of the shell, reduce shell defects, and improve product yield. The bending strength of the shell is in the range of 50MPa-350Mpa. When the shell is impacted, it is not easy to deform, and the processing difficulty of the shell is small, and the product yield is high. The thermal deformation temperature of the shell is ≥110℃, which makes the shell have strong high temperature resistance and is not easy to deform during high temperature and high humidity reliability and high power reliability verification.

[0157] The above embodiments focus on the differences between the various embodiments. As long as the different optimization features between the various embodiments are not contradictory, they can be combined to form a better embodiment. Considering the simplicity of the text, they will not be repeated here.

[0158] Although some specific embodiments of the present invention have been described in detail by way of example, it will be appreciated by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present invention. It will be appreciated by those skilled in the art that the above embodiments may 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 housing of a sound-generating device, characterized in that: The invention comprises a first shell and a second shell, wherein the first shell and the second shell are both provided with a welding portion, the welding portion of the first shell and the welding portion of the second shell are connected by ultrasonic welding, and the welding portion is formed by injection molding of a composite material consisting of carbon fiber and an alloy material, wherein the mass ratio of the carbon fiber to the alloy material is 0.10-0.65, the alloy material comprises a first component and a second component, the first component is polyphenylene ether, and the second component is at least one of polystyrene, polyamide, ABS, and PBT, the mass ratio of the second component to the first component is 0.05-0.45, and the melting enthalpy of the alloy material is ≤10J / g.

2. The housing of the sound-generating device according to claim 1, characterized in that: The glass transition temperature of the alloy material is ≥110°C.

3. The housing of the sound-generating device according to claim 1, characterized in that: The composite material further comprises hollow glass microspheres, and the distribution density of the hollow glass microspheres in the composite material is 0.1 g / cm 3 -0.8g / cm 3 .

4. The housing of the sound-generating device according to claim 1, characterized in that: The carbon content of the carbon fiber is 90%-99.99%, and / or the graphitization degree R of the carbon fiber is 0.85-1.15, and / or the length of the carbon fiber is 0.1mm-1mm.

5. The housing of the sound-generating device according to claim 1, characterized in that: The carbon fiber is sizing treated with a sizing agent, and the sizing agent includes at least one of a polystyrene sizing agent, a polyamide sizing agent, a polyester sizing agent, and an epoxy resin sizing agent.

6. The housing of the sound-generating device according to claim 1, characterized in that: The entirety of at least one of the first shell and the second shell is a welded portion; or At least one of the first shell and the second shell includes a support portion, and the support portion is integrally injection-molded with the welding portion.

7. The housing of the sound-generating device according to claim 6, characterized in that: The supporting portion includes a resin material, and the resin material includes at least one of PP, PA610, PA612, PA1010, PA11, PA12, PA1212, PA1012, PA1111, PA1213, PA1313, PPA, PA4T, PA6T, PA9T, PA10T, PA12T, PA46, ABS, PET, PBT, and PC.

8. The housing of the sound-generating device according to claim 7, characterized in that: The support portion further includes a fiber material, the resin material is mixed with the fiber material, and a mass ratio of the fiber material to the resin material is 0.1 to 0.

7.

9. The housing of the sound-generating device according to claim 1, characterized in that: The density of the shell is 0.9 g / cm 3 -1.3g / cm 3 ; And / or, more than 20% of the area of ​​the shell has a thickness of ≤0.3 mm.

10. The housing of the sound-generating device according to claim 1, characterized in that: The bending modulus of the shell is 5GPa-35GPa; And / or, the bending strength of the shell is 50MPa-350Mpa; And / or the heat deformation temperature of the shell is ≥110°C.

11. The housing of the sound-generating device according to any one of claims 1 to 10, characterized in that: The waterproof rating of the housing is not less than 1ATM.

12. A sound-generating device, characterized in that: A housing comprising the sound emitting device according to any one of claims 1 to 11.

13. An electronic device, characterized in that: Comprising the sound-generating device as claimed in claim 12.

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