Housing of sound generation apparatus, sound generation apparatus, and electronic device

Abstract

Disclosed are a housing of a sound generation apparatus, a sound generation apparatus, and an electronic device. The housing comprises a reinforcing portion, the thickness of the reinforcing portion is less than or equal to 0.3 mm, and the reinforcing portion is formed by injection molding of a polyamide composite material consisting of carbon fibers and a polyamide. In the reinforcing portion, the mass ratio of the carbon fibers to the polyamide is 0.42-1, the density of the reinforcing portion is 1.2 g / cm3-1.45 g / cm3, and the flexural modulus of the reinforcing portion is 20 GPa-40 GPa. In the present invention, the reinforcing portion is formed by injection molding of the polyamide composite material, and the polyamide composite material comprises the carbon fibers and the polyamide mixed together. The carbon fibers can significantly improve the strength and modulus of the polyamide composite material. The housing does not need to be injection-molded containing a steel piece for thinning and improving the structural strength, the housing has good structural consistency and sealing performance, and the structural strength meets actual use requirements. Furthermore, the processing process of the housing is simplified, and the product yield is high.

Description

The housing of the sound-generating device, the sound-generating device, and electronic equipment Technical Field

[0001] This invention relates to the field of electroacoustic conversion technology, and more specifically, to a housing of a sound-generating device, a sound-generating device, and an electronic device. Background Technology

[0002] In related technologies, speaker module housings are typically constructed using PC+glass fiber reinforced plastic material and steel inserts. This type of housing offers good structural strength and a relatively low price. However, a drawback is the excessively high density of the steel inserts; for example, the density of the steel inserts is 7.8 g / cm³. 3 Excessive density is detrimental to the lightweight requirements of speaker modules and electronic products.

[0003] Furthermore, the bonding between the plastic material and the steel insert in the speaker module housing is not strong, which can easily lead to waterproofing failure. The speaker module housing is manufactured using injection molding. The different shrinkage rates of the plastic material and the steel insert can easily cause housing deformation, resulting in difficulties in housing assembly and speaker module performance failure.

[0004] Therefore, a new technical solution is needed to solve the above-mentioned technical problems. Summary of the Invention

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

[0006] According to a first aspect of the present invention, a housing for a sound-generating device is provided. The housing includes a reinforcing portion with a thickness ≤0.3 mm, the reinforcing portion being injection molded from a polyamide composite material composed of carbon fiber and polyamide, wherein the mass ratio of the carbon fiber to the polyamide in the reinforcing portion is 0.42-1, and the density of the reinforcing portion is 1.2 g / cm³. 3 -1.45g / cm 3 The bending modulus of the reinforcing part is 20GPa-40GPa.

[0007] Optionally, the polyamide includes a semi-aromatic polyamide, which includes at least one of PPA, PA46, PA4T, PA5T, PA6T, PA9T, PA10T, and PA12T.

[0008] Optionally, the carbon fiber has a carbon content of 92%-99.99%, and / or the degree of graphitization R of the carbon fiber is 0.8-1.05, and / or the length of the carbon fiber is 0.1mm-1mm, and / or the orientation angle of the graphite crystals of the carbon fiber is ≤25°.

[0009] Optionally, the carbon fiber is sized with a sizing agent, which includes at least one of polyamide sizing agent, polyurethane sizing agent, and epoxy resin sizing agent.

[0010] Optionally, the housing has an internal receiving cavity, and at least a portion of the wall of the receiving cavity is formed by the reinforcing portion.

[0011] Optionally, the receiving cavity includes a front acoustic cavity and a rear acoustic cavity, and at least a portion of the walls of the front acoustic cavity and / or the rear acoustic cavity are formed by the reinforcing portion.

[0012] Optionally, the entire housing is composed of the reinforcing portion.

[0013] Optionally, the housing further includes a base portion, which is integrally injection molded with the reinforcing portion.

[0014] Optionally, the matrix portion includes a resin material, which 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.

[0015] Optionally, the matrix further includes a fiber material, which includes carbon fiber and / or glass fiber, and the resin material is mixed with the fiber material, wherein the mass ratio of the fiber material to the resin material is 0.25-1.

[0016] Optionally, the bending strength of the reinforcing part is 200MPa-450MPa;

[0017] And / or, the heat distortion temperature of the reinforcing part is ≥250℃.

[0018] According to a second aspect of the present invention, a sound-generating device is provided. The device includes a housing of the sound-generating device described in the present invention.

[0019] Optionally, the sound-generating device further includes a sound-generating unit disposed within the housing, the sound-generating unit including a vibration system, and the housing, at least partially opposite to the sound-generating unit, is composed of the reinforcing portion along the vibration direction of the vibration system.

[0020] According to a third aspect of the present invention, an electronic device is provided. This electronic device includes the sound-generating device described in the present invention.

[0021] In an embodiment of the invention, the housing of the sound-generating device includes a reinforcing portion, which is a polyamide composite material. The polyamide composite material comprises carbon fibers and polyamide mixed together. In the reinforcing portion, the mass ratio of the carbon fibers to the polyamide is 0.42-1, and the density of the reinforcing portion is 1.2 g / cm³. 3 -1.45g / cm 3 The flexural modulus of the reinforcing part is 20 GPa-40 GPa. Since the polyamide composite material used to make the reinforcing part includes a mixture of carbon fiber and polyamide, the flexural modulus of the reinforcing part is as high as 20 GPa-40 GPa. While meeting the structural strength requirements of the shell, the thickness of the reinforcing part can be made thinner, ≤0.3 mm, thereby increasing the volume of the internal cavity of the shell and improving the sound-generating effect of the sound-generating device. Carbon fiber can significantly improve the strength, modulus, and thermal conductivity of the polyamide composite material, and in reliability verification, it is less likely to cause resonance between the shell and the sound-generating unit. The shell has high modulus and strength, and good thermal conductivity. Furthermore, the shell is injection molded from polyamide composite material, resulting in good overall consistency and avoiding problems such as shell deformation and waterproofing failure that can occur with injection-molded steel sheets in plastic shells. In addition, the shell does not require injection-molded steel sheets for thinning, thermal conductivity, and maintaining structural strength, thus simplifying the shell processing technology and resulting in a high product yield.

[0022] Other features and advantages of the invention will become clear from the following detailed description of exemplary embodiments of the invention with reference to the accompanying drawings. Attached Figure Description

[0023] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of the invention and, together with their description, serve to explain the principles of the invention.

[0024] Figure 1 is a cross-sectional view of a sound-generating device according to an embodiment of the present invention.

[0025] Explanation of reference numerals in the attached drawings: 10, first housing; 11, top wall; 111, front acoustic cavity; 121, rear acoustic cavity; 15, side wall edge; 20, sound-generating unit; 30, PCB; 40, second housing; 41, bottom wall. Detailed Implementation

[0026] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention.

[0027] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the invention or its application or use.

[0028] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0029] In all the examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0030] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0031] According to one embodiment of the present invention, a housing for a sound-generating device is provided. The housing includes a reinforcing portion with a thickness ≤0.3 mm. The reinforcing portion is a polyamide composite material, wherein the polyamide composite material comprises carbon fibers and polyamide mixed together. In the reinforcing portion, the mass ratio of the carbon fibers to the polyamide is 0.42-1, and the density of the reinforcing portion is 1.2 g / cm³. 3 -1.45g / cm 3 The bending modulus of the reinforcing part is 20GPa-40GPa.

[0032] Specifically, as shown in Figure 1, the first housing 10 and the second housing 40 are connected together to form a receiving cavity within them. The receiving cavity is used to accommodate the sound-generating unit 20 and the PCB 30. The sound-generating unit 20 is connected to the PCB 30. A front acoustic cavity is formed between the first housing 10 and the sound-generating unit 20, and the front acoustic cavity has a sound outlet. The sound outlet is used to radiate sound waves outward. The front acoustic cavity can adjust the mid- and high-frequency effects of the sound-generating device. A rear acoustic cavity is formed between the second housing 40 and the sound-generating unit 20. The rear acoustic cavity can adjust the low-frequency effects of the sound-generating device. The PCB 30 is connected to an external circuit. The first housing 10 includes a top wall 11 and a first side wall, and the second housing 40 includes a bottom wall 41 and a second side wall. The side wall edges 15 of the first and second side walls are ultrasonically welded or glued together. Reinforcing portions are provided at least partially on the top wall 11, the bottom wall 41, the first side wall, and the second side wall. Further, the top wall 11, the bottom wall 41, the first side wall, and / or the second side wall are integrally reinforced portions. Alternatively, one of the first housing 10 and the second housing 40 may be a flat plate structure. Reinforcing portions are provided in at least a portion of the first housing 10 and the second housing 40.

[0033] In this embodiment, since the polyamide composite material used to form the reinforcing part comprises a mixture of carbon fiber and polyamide, the flexural modulus of the reinforcing part is as high as 20GPa-40GPa. While meeting the structural strength requirements of the shell, the thickness of the reinforcing part can be made thinner, ≤0.3mm. Due to the smaller thickness of the reinforcing part, the space for accommodating cavities within the shell is larger, resulting in a larger volume of the front acoustic cavity and / or rear acoustic cavity, thereby enabling more effective adjustment of the sound-generating effect of the sound-generating device.

[0034] Furthermore, the reinforcing part is a polyamide composite material. The polyamide composite material comprises carbon fibers and polyamide mixed together. Polyamide, also known as nylon, is a high-molecular-weight polymer containing repeating amide groups (-NHCO-) ​​in its main chain. It can be produced through reactions such as lactam ring-opening polymerization or condensation polymerization of diamines with diacids. Polyamides possess high strength, high rigidity, high heat resistance, and high toughness, resulting in high modulus and strength. Carbon fiber is a high-strength, high-modulus, high-performance fiber material, produced from organic fibers (such as polyacrylonitrile, viscose fiber, or pitch) through carbonization and other processes. Carbon fibers exhibit high strength and modulus in the fiber direction, and their density is lower than that of glass fibers. Carbon fiber reinforcement of the shell structure provides superior strength, allowing for a lower addition amount of carbon fiber in the polyamide composite material while meeting the shell's strength and modulus requirements, thus facilitating lightweighting of the shell. Furthermore, the good thermal conductivity of carbon fiber contributes to the shell's excellent thermal conductivity, resulting in superior strength, modulus, and thermal conductivity in the polyamide composite material.

[0035] The mass ratio of carbon fiber to polyamide is 0.42-1. When the mass ratio of carbon fiber to polyamide is greater than 1, the high distribution density of carbon fiber in the polyamide composite material results in excessively high viscosity, making it prone to short-filling during injection molding. Conversely, when the mass ratio of carbon fiber to polyamide is less than 0.42, the reinforcing effect of carbon fiber on the polyamide composite material is poor, and the shell is prone to resonance in the mid-frequency stage during the reliability verification of the sound-generating device, leading to excessively high mid-frequency THD distortion. When the mass ratio of carbon fiber to polyamide is 0.42-1, the shell is less prone to short-filling during injection molding, and the shell has high strength and modulus. Optionally, the mass ratio of the carbon fiber to the polyamide is 0.42, 0.45, 0.46, 0.50, 0.55, 0.60, 0.65, 0.67, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, 1, etc. All of the above values ​​can make the polyamide composite material less prone to defects, the overall structural strength of the formed shell is high, and the polyamide composite material has high modulus and strength.

[0036] Because polyamide has a low density, when combined with carbon fiber, the density of the reinforcing part is 1.2 g / cm³. 3 -1.45g / cm 3 The density of the reinforced section is <1.2 g / cm³. 3 If the carbon fiber content in the polyamide composite material is too high, it can easily lead to insufficient glue in the shell during injection molding; conversely, if the density of the reinforcing part is >1.45 g / cm³, it can cause problems. 3 In this case, the overall weight of the casing may become too large, failing to meet the requirements for lightweight casing. In this embodiment, the density of the reinforcing part is 1.2 g / cm³. 3 -1.45g / cm 3 Within this range, the shell has few defects and meets the requirements for lightweight shell design. Optionally, the density of the reinforcement is 1.2 g / cm³. 3 1.25g / cm 3 1.3g / cm 3 1.35g / cm 3 1.4g / cm 3 1.45g / cm 3 The above values ​​all contribute to minimizing defects in the casing and meeting the requirements for lightweight casing.

[0037] The flexural modulus of the reinforcing part is 20 GPa-40 GPa. Flexural modulus reflects a material's ability to resist deformation under bending loads. If the flexural modulus of the shell is too low, for example, less than 20 GPa, local vibrations are likely to occur in the shell, potentially resonating with the vibrations of the sound-generating monomer 20, resulting in poor sound production. Conversely, if the flexural modulus of the shell is too high, for example, greater than 40 GPa, it increases the processing difficulty of the shell and reduces product yield. For instance, when using polyamide composite materials to prepare the shell, it is necessary to increase the amount of carbon fiber added; for example, a carbon fiber to polyamide mass ratio greater than 1 can lead to excessively high viscosity of the polyamide melt, making it prone to fiber exposure and insufficient glue during injection molding. In this embodiment, the flexural modulus of the shell is 20 GPa-40 GPa. Within this range, resonance between the shell and the sound-generating monomer 20 can be avoided, while also reducing the processing difficulty of the shell, minimizing shell defects, and improving product yield. Furthermore, due to the high flexural modulus of the reinforcing section, it can be made thinner, for example, with a thickness ≤0.3mm. This results in a larger cavity volume, and the shell possesses sufficient structural strength, eliminating the need for injection-molded steel sheets to enhance its strength. This simplifies the shell's manufacturing process. Optionally, the shell's flexural modulus can be 20GPa, 25GPa, 30GPa, 35GPa, or 40GPa. These values ​​all prevent resonance between the shell and the sound-generating unit 20, reduce the shell's manufacturing difficulty, and improve product yield.

[0038] The manufacturing process of the shell of the present invention may include:

[0039] (1) Preparation of polyamide composite material. Polyamide is fed into a twin-screw extruder through the main feed port for melting. After the polyamide melts, carbon fibers are added through the side feed port. The carbon fibers and the molten polyamide are sheared and mixed evenly in the extruder, and then extruded and granulated.

[0040] (2) Preparation of the shell. The granulated polyamide composite material is remelted during injection molding and then injected into a mold to form the first shell 10 and the second shell 40.

[0041] (3) Assemble the sound-generating unit 20 and PCB 30 and other components into the receiving cavity formed by the first housing 10 and the second housing 40. Then, align the two side wall edges 15 of the first housing 10 and the second housing 40 and perform ultrasonic welding or bonding to connect the two side wall edges 15 together.

[0042] It should be noted that carbon fiber has a large aspect ratio and low resistance to shear forces. Therefore, carbon fiber is usually added after the polyamide has melted. This can effectively reduce the damage to carbon fiber during the mixing process, thereby improving the reinforcing effect of carbon fiber on polyamide composites.

[0043] In an embodiment of the invention, the housing of the sound-generating device includes a reinforcing portion, which is a polyamide composite material. The polyamide composite material comprises carbon fibers and polyamide mixed together. In the reinforcing portion, the mass ratio of the carbon fibers to the polyamide is 0.42-1, and the density of the reinforcing portion is 1.2 g / cm³. 3 -1.45g / cm 3 The flexural modulus of the reinforcing part is 20 GPa-40 GPa. Since the polyamide composite material used to make the reinforcing part includes a mixture of carbon fiber and polyamide, the flexural modulus of the reinforcing part is as high as 20 GPa-40 GPa. While meeting the structural strength requirements of the shell, the thickness of the reinforcing part can be made thinner, ≤0.3 mm, thereby increasing the volume of the internal cavity of the shell and improving the sound-generating effect of the sound-generating device. Carbon fiber can significantly improve the strength, modulus, and thermal conductivity of the polyamide composite material. In reliability verification, the phenomenon of resonance between the shell and the sound-generating unit is less likely to occur, and the shell has good thermal conductivity. It has high modulus and strength, and good thermal conductivity. Furthermore, the shell does not require injection-molded steel sheets for thinning, thermal conductivity, and maintaining structural strength, thus avoiding cracking between the steel sheets and the injection-molded material, simplifying the shell processing technology, and resulting in a high product yield.

[0044] In one specific embodiment of the present invention, the polyamide includes a semi-aromatic polyamide, which includes at least one of PPA, PA46, PA4T, PA5T, PA6T, PA9T, PA10T, and PA12T.

[0045] Semi-aromatic polyamides are polymeric materials produced by the polycondensation reaction of aliphatic diamines or diacids with aromatic diacids or diamines. Semi-aromatic polyamides possess excellent high-temperature resistance and high initial modulus, resulting in polyamide composites with higher stiffness, modulus, and better high-temperature resistance. Optionally, the semi-aromatic polyamide includes at least one of PPA, PA46, PA4T, PA5T, PA6T, PA9T, PA10T, and PA12T. That is, any one of the above semi-aromatic polyamides can be selected, or a mixture of at least two of the above semi-aromatic polyamides can be selected.

[0046] In one specific embodiment of the present invention, the carbon fiber has a carbon content of 92%-99.99%, and / or the degree of graphitization R of the carbon fiber is 0.8-1.05, and / or the length of the carbon fiber is 0.1mm-1mm, and / or the orientation angle of the graphite crystals of the carbon fiber is ≤25°.

[0047] Specifically, the lower the carbon content of the carbon fiber, the lower its modulus; conversely, the higher the carbon content, the higher its modulus. In this embodiment, the carbon content of the carbon fiber is 92%-99.99%. Within this range, under the same mass content conditions, the polyamide composite material has a high modulus and high overall structural strength of the shell. Optionally, the carbon content of the carbon fiber can be 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99.99%, etc. All of these values ​​result in high modulus and strength of the polyamide composite material, and high overall structural strength of the shell.

[0048] Furthermore, the length of the carbon fiber is 0.1mm-1mm. When the carbon fiber length is less than 0.1mm, the strength of the shell decreases with the same carbon fiber content, leading to breakage in drop reliability tests. When the carbon fiber length is greater than 1mm, the shell is prone to fiber exposure and floating fiber issues during injection molding, affecting product yield. In this embodiment, the carbon fiber length is 0.1mm-1mm. Within this range, the shell has high structural strength, and the shell is less prone to fiber exposure and floating fiber issues during injection molding, resulting in high product yield. Optionally, the carbon fiber length can be 0.1mm, 0.2mm, 0.3mm, 0.2mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, etc. All of these values ​​contribute to high structural strength of the shell and reduce the likelihood of fiber exposure and floating fiber issues during injection molding.

[0049] The orientation angle of graphite crystallites refers to the angle between the crystal plane of the graphite crystallites and the fiber direction. The smaller the orientation angle of the graphite crystallites in carbon fibers, the higher the modulus in the fiber direction, and the greater the effect on improving the modulus of the polyamide composite material. In this embodiment, the orientation angle of the graphite crystallites in the carbon fibers is ≤25°. Within this range, the carbon fibers have a high modulus in the fiber direction, resulting in a high modulus of the polyamide composite material. Optionally, the orientation angle of the graphite crystallites in the carbon fibers can be 15°, 17°, 19°, 20°, 22°, 24°, 25°, etc. All of these values ​​result in a high modulus of the polyamide composite material.

[0050] In other embodiments, the carbon fibers satisfy at least two of the above conditions. This polyamide composite material exhibits high modulus and strength, and is less prone to problems such as exposed or floating fibers.

[0051] In one specific embodiment of the present invention, the carbon fiber is treated with a sizing agent, the sizing agent including at least one of polyamide sizing agent, polyurethane sizing agent, and epoxy resin sizing agent.

[0052] In this embodiment, the carbon fiber surface is inert, resulting in poor compatibility and low bonding strength with polyamide. During the preparation of the polyamide composite material, surface treatment of the carbon fiber is necessary to improve its compatibility with polyamide. A sizing agent is used to sizing the carbon fiber. The sizing agent includes at least one of polyamide sizing agent, polyurethane sizing agent, and epoxy resin sizing agent. All of these sizing agents can improve the bonding strength between carbon fiber and polyamide, thus enhancing their compatibility.

[0053] In one specific embodiment of the present invention, the interior of the housing is provided with a receiving cavity, and at least a portion of the wall of the receiving cavity is formed by the reinforcing portion.

[0054] As shown in Figure 1, the first housing 10 and the second housing 40 are connected to form a receiving cavity inside the housing. The receiving cavity houses the sound-generating unit 20 and the PCB030. The walls of the receiving cavity include a top wall 11, a bottom wall 41, a first side wall, and a second side wall. The side wall edges 15 of the first and second side walls are ultrasonically welded or glued together. Reinforcing portions are provided at least partially on the top wall 11, the bottom wall 41, the first side wall, and / or the second side wall. This arrangement significantly increases the volume of the receiving cavity, thereby enabling more effective adjustment of the sound-generating effect of the sound-generating device.

[0055] In one specific embodiment of the present invention, the cavity includes a front acoustic cavity and a rear acoustic cavity, and at least a portion of the wall of the front acoustic cavity and / or the rear acoustic cavity is formed by the reinforcing portion.

[0056] As shown in Figure 1, a front acoustic cavity is formed between the first housing 10 and the sound-generating unit 20, and the front acoustic cavity has a sound outlet. The sound outlet is used to radiate sound waves outward. The front acoustic cavity can adjust the mid- and high-frequency effects of the sound-generating device. A rear acoustic cavity is formed between the second housing 40 and the sound-generating unit 20. The rear acoustic cavity can adjust the low-frequency effects of the sound-generating device. In this embodiment, at least a portion of the walls of the front acoustic cavity (e.g., the top wall 11 and the first side wall) or the walls of the rear acoustic cavity (e.g., the bottom wall 41 and the second side wall) are formed by reinforcement; or at least a portion of the walls of the front acoustic cavity (e.g., the top wall 11 and the first side wall) and the walls of the rear acoustic cavity (e.g., the bottom wall 41 and the second side wall) are formed by reinforcement. Since the thickness of the reinforcement is small, the volume of the front acoustic cavity and / or the rear acoustic cavity can be effectively increased, thereby improving the sound-generating effect of the sound-generating device.

[0057] In one specific embodiment of the present invention, the entire housing is composed of the reinforcing portion.

[0058] In other words, in this embodiment, the first housing 10 and / or the second housing 40 are integrally injection molded from a polyamide composite material, which comprises a mixture of polyamide and carbon fiber. The thickness of the reinforcing portion is ≤0.3mm, the mass ratio of the carbon fiber to the polyamide is 0.42-1, and the density of the reinforcing portion is 1.2g / cm³. 3 -1.45g / cm 3 The flexural modulus of the reinforcing part is 20 GPa-40 GPa. As mentioned above, the shell has the characteristics of high modulus, high strength, light weight, and good thermal conductivity. For example, the first shell 10 is entirely injection molded from polyamide composite material, and a portion of the structure of the second shell 40 is integrally injection molded from polyamide composite material; or, a portion of the structure of the first shell 10 is integrally injection molded from polyamide composite material, and the second shell 40 is entirely injection molded from polyamide composite material; or, both the first shell 10 and the second shell 40 are entirely injection molded from polyamide composite material.

[0059] In one specific embodiment of the present invention, the housing further includes a base portion, which is integrally injection molded with the reinforcing portion.

[0060] Specifically, as shown in Figure 1, for the first housing 10, the reinforcing portion is located on the top wall 11, and the first side wall includes the base portion; or the reinforcing portion is located on the first side wall, and the top wall 11 includes the base portion. For the second housing 40, the reinforcing portion is located on the bottom wall 41. The second side wall includes the base portion; or the reinforcing portion is located on the second side wall, and the top wall 41 includes the base portion. During injection molding, for example, the base portion is formed in one injection, and the reinforcing portion is formed on the base portion in a second injection. After curing, the base portion and the reinforcing portion are connected together. In this embodiment, the base portion and the reinforcing portion can be processed into a set shape according to actual needs to meet the sound generation requirements of different sound-generating devices. In this configuration, different parts of the first housing 10 and / or the second housing 40 can be made of different materials according to different functions. The different materials are formed by integral injection molding. The processing technology of the first housing 10 and / or the second housing 40 is simple, and the structural strength is high.

[0061] In one specific embodiment of the present invention, the matrix portion includes a resin material, which 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.

[0062] When preparing the base material, any one of the above-mentioned materials can be selected, or at least two of the above-mentioned materials can be mixed together. All of the above materials can be processed into a predetermined structure according to the sound-generating requirements of the sound-generating device.

[0063] In one specific embodiment of the present invention, the matrix further includes a fiber material, the fiber material including carbon fiber and / or glass fiber, and the resin material is mixed with the fiber material, wherein the mass ratio of the fiber material to the resin material is 0.25-1.

[0064] In this embodiment, the fiber material is, for example, carbon fiber and / or glass fiber. The resin material and fiber material are mixed together to form a polyamide composite material, where the fiber material significantly improves the modulus and strength of the polyamide composite material. When the mass ratio of fiber material to resin material is less than 0.25, the fiber material has a relatively small effect on improving the modulus and strength of the polyamide composite material; conversely, when the mass ratio of fiber material to resin material is greater than 1, the resulting polyamide composite material has a high density, failing to meet the requirements for lightweight shells. In this embodiment, the mass ratio of the fiber material to the resin material is 0.25-1. Within this range, the polyamide composite material possesses both high strength and modulus, and the resulting shell is lightweight. Optionally, the mass ratio of the fiber material to the resin material can be 0.25, 0.30, 0.40, 0.50, 0.60, 0.70, 0.8, 0.9, 1, etc., all of which result in the polyamide composite material possessing both high strength and modulus, and the resulting shell being lightweight.

[0065] In one specific embodiment of the present invention, the bending strength of the reinforcing part is 200MPa-450MPa;

[0066] And / or, the heat distortion temperature of the reinforcing part is ≥250℃.

[0067] Bending strength is the maximum normal stress a material can withstand when it reaches a specified deflection or fractures under bending load. When the bending strength of the shell is <200MPa, the shell is prone to deformation or even fracture upon impact; when the bending strength is >450MPa, the shell has poor flowability during injection molding, making processing difficult. In this embodiment, the bending strength of the shell is 200MPa-450MPa. Within this range, the shell is less prone to deformation upon impact, and the processing difficulty is low, resulting in a high product yield. Optionally, the bending strength of the shell can be 200MPa, 250MPa, 300MPa, 350MPa, 400MPa, 450MPa, etc. These values ​​all result in excellent impact resistance, low processing difficulty, and a high product yield.

[0068] In one specific embodiment of the present invention, the heat deformation temperature of the housing is ≥250°C.

[0069] Heat distortion temperature reflects a material's ability to resist deformation under heat and load conditions. A higher heat distortion temperature indicates that the shell can maintain structural stability under more demanding conditions. In this embodiment, the heat distortion temperature of the shell is ≥250℃, resulting in strong high-temperature resistance and reduced deformation during high-temperature, high-humidity reliability and high-power reliability verification. Optionally, the heat distortion temperature of the shell can be 250℃, 260℃, 270℃, 300℃, 320℃, 330℃, 350℃, etc. All of these values ​​contribute to strong high-temperature resistance and reduced deformation during high-temperature, high-humidity reliability and high-power reliability verification.

[0070] In one specific embodiment of the present invention, the bending strength of the shell is 200MPa-450MPa, and the heat distortion temperature of the shell is ≥250℃. In other words, the performance of the shell meets the above two conditions. This significantly improves the shell's resistance to deformation and its high-temperature resistance, while also reducing processing difficulty.

[0071] According to a second embodiment of the present invention, a sound-generating device is provided. The sound-generating device includes the housing of the sound-generating device described in the present invention.

[0072] As shown in Figure 1, the sound-generating device of the present invention includes a housing, a sound-generating unit 20, and a PCB 30. The housing includes a first housing 10 and a second housing 40. The first housing 10 and the second housing 40 are connected together to form a receiving cavity therein. The receiving cavity is used to accommodate the sound-generating unit 20 and at least a portion of the PCB 30. A front acoustic cavity 111 is formed between the first housing 10 and the sound-generating unit 20. The front acoustic cavity 111 has a sound outlet. A rear acoustic cavity 121 is formed between the second housing 40 and the sound-generating unit 20. The sound-generating unit 20 is connected to the PCB 30. The PCB 30 is connected to an external circuit. The edges of both the first housing 10 and the second housing 40 are provided with sidewall edges 15. The sidewall edges 15 of the first housing 10 and the second housing 40 are joined together by ultrasonic welding or adhesive.

[0073] This sound-generating device features high structural strength, good high-temperature resistance, and excellent sound generation effect.

[0074] In one specific embodiment of the present invention, the sound-generating device further includes a sound-generating unit disposed within the housing, the sound-generating unit including a vibration system, and the housing, at least partially opposite to the sound-generating unit, is composed of the reinforcing portion along the vibration direction of the vibration system.

[0075] As shown in Figure 1, the interior of the housing forms a front acoustic cavity 111 and a rear acoustic cavity 121. A sound-generating unit is located between the front acoustic cavity 111 and the rear acoustic cavity 121. The front acoustic cavity 111 has a sound outlet. The sound outlet is used to radiate sound waves outwards. The sound-generating unit 20 includes a vibration system. The vibration direction of the vibration system is shown by the arrow in Figure 1. Along the vibration direction of the vibration system, the housing at least partially opposite the sound-generating unit is, for example, at least a portion of the top wall 11 or at least a portion of the bottom wall 41; it can also be at least a portion of both the top wall 11 and the bottom wall 41. When the reinforcing portion is located on the top wall 11, because the thickness of the reinforcing portion is relatively thin, for example, ≤0.3mm, the front acoustic cavity 111 has a larger dimension along the vibration direction for the same housing size, thereby allowing for a larger vibration amplitude of the sound-generating unit's vibration system, resulting in a better sound generation effect. When the reinforcing portion is located on the bottom wall 41, the rear acoustic cavity 121 has a larger dimension in the vibration direction, resulting in a better low-frequency effect of the sound generation device. Alternatively, the reinforcing part can be located on both the top wall 11 and the bottom wall 41, so that the sound-generating device can have both of the above advantages, which makes the sound-generating device have a better sound-generating effect.

[0076] According to a third embodiment of the present invention, an electronic device is provided. This electronic device includes the sound-generating device described in this invention. The electronic device is characterized by its good durability. Optionally, the electronic device may be a computer, mobile phone, watch, television set, speaker, AR device, VR device, vehicle, etc.

[0077] The housing and the sound-generating device according to embodiments of the present invention will be described in detail below with reference to specific embodiments and comparative examples. It is worth understanding that the following description is merely exemplary and not a specific limitation of the present invention.

[0078] Comparative Example 1

[0079] A housing is formed by injection molding of steel sheets and PPA materials with inserts located on the top wall 11. The resulting housing is then assembled with the sound-generating unit 20 to obtain a sound-generating device.

[0080] Example 1

[0081] The shell is formed by injection molding using 70wt% PPA material and 30wt% carbon fiber, with the reinforcing part located on the top wall 11. The resulting shell is then assembled with the sound-generating unit 20 to obtain the sound-generating device.

[0082] Example 2

[0083] The shell is formed by injection molding using 65wt% PPA material and 35wt% carbon fiber, with the reinforcing part located on the top wall 11. The resulting shell is then assembled with the sound-generating unit 20 to obtain the sound-generating device.

[0084] Example 3

[0085] The shell is formed by injection molding using 60wt% PPA material and 40wt% carbon fiber, with the reinforcing part located on the top wall 11. The resulting shell is then assembled with the sound-generating unit 20 to obtain the sound-generating device.

[0086] Example 4

[0087] The shell is formed by injection molding using 55wt% PPA material and 45wt% carbon fiber, with the reinforcing part located on the top wall 11. The resulting shell is then assembled with the sound-generating unit 20 to obtain the sound-generating device.

[0088] Example 5

[0089] A shell is formed by injection molding using 50wt% PPA material and 50wt% carbon fiber, with the reinforcing part located on the top wall 11. The resulting shell is then assembled with the sound-generating unit 20 to obtain a sound-generating device.

[0090] Example 6

[0091] A shell is formed by injection molding using 65wt% PA4T and 35wt% carbon fiber, with the reinforcing part located on the top wall 11. The resulting shell is then assembled with the sound-generating unit 20 to obtain a sound-generating device.

[0092] Example 7

[0093] A shell is formed by injection molding using 60wt% PA5T and 40wt% carbon fiber, with the reinforcing part located on the top wall 11. The resulting shell is then assembled with the sound-generating unit 20 to obtain a sound-generating device.

[0094] Example 8

[0095] A shell is formed by injection molding using 55wt% PA6T and 45wt% carbon fiber, with the reinforcing part located on the top wall 11. The resulting shell is then assembled with the sound-generating unit 20 to obtain a sound-generating device.

[0096] Example 9

[0097] A shell is formed by injection molding using 60wt% PA9T and 40wt% carbon fiber, with the reinforcing part located on the top wall 11. The resulting shell is then assembled with the sound-generating unit 20 to obtain a sound-generating device.

[0098] Example 10

[0099] A shell is formed by injection molding using 65wt% PA10T and 35wt% carbon fiber, with the reinforcing part located on the top wall 11. The resulting shell is then assembled with the sound-generating unit 20 to obtain a sound-generating device.

[0100] Example 11

[0101] A shell is formed by injection molding using 55wt% PA12T and 45wt% carbon fiber, with the reinforcing part located on the top wall 11. The resulting shell is then assembled with the sound-generating unit 20 to obtain a sound-generating device.

[0102] It should be noted that the external dimensions of the shells in the comparative examples and embodiments are consistent. For ease of comparison, the raw material ratios of Comparative Example 1 and Examples 1-11 are shown in Table 1.

[0103] Table 1 - Raw material proportions for the shells of the embodiments and comparative examples

[0104] The steel sheet of Comparative Example 1 and the shells of Examples 1-11 were tested for heat distortion temperature, density, flexural modulus and flexural strength, respectively. The test results are shown in Tables 2 and 3.

[0105] The testing conditions and standards are as follows:

[0106] (1) Flexural modulus and flexural strength test: The test shall be conducted in accordance with GB / T 9341-2008 standard for determination of flexural properties of plastics.

[0107] (2) Heat distortion temperature test: The test shall be conducted in accordance with GB / T 1634.2-2004 Plastics - Determination of heat distortion temperature - Part 2: Plastics, hard rubber and long fiber reinforced polyamide composites.

[0108] (3) Density test method: The density shall be tested in accordance with GB / T 1033.1-2008 Determination of density of non-foamed plastics - Part 1: Immersion method, liquid specific gravity bottle method and titration method, using the immersion method.

[0109] Table 2 - Performance Test Comparison Table of the Shell of the Example and the Steel Sheet of the Comparative Example

[0110] As shown in Table 2, the heat distortion temperature of the shells in Examples 1-11 is ≥270℃. The bending strength of the shells in Examples 1-11 is between 200MPa and 450MPa. The bending strength of the steel sheet in Comparative Example 1 is 500MPa. The bending modulus of the shells in Examples 1-11 is between 20GPa and 40GPa. The bending modulus of the steel sheet in Comparative Example 1 is 195GPa.

[0111] Furthermore, the density of the shells in Examples 1-11 is all around 1.2 g / cm³. 3 -1.45g / cm 3 This density meets the requirements for lightweight casing. The density of the steel sheets in Comparative Example 1 is ≥7.93 g / cm³. 3 This density does not meet the requirements for lightweight casing.

[0112] Therefore, the shells of Examples 1-11 are injection molded from polyamide composite materials. The polyamide composite material comprises carbon fibers and polyamide mixed together, with a mass ratio of carbon fibers to polyamide of 0.42-1. The density of the reinforcing portion is 1.2 g / cm³. 3 -1.45g / cm 3 The flexural modulus of the reinforcing part is 20GPa-40GPa, and the thickness of the reinforcing part is ≤0.3mm. This results in high heat distortion temperature, flexural modulus, and flexural strength of the shells in Examples 1-11, indicating high structural strength, minimal strength loss during high-temperature operation, and strong structural stability. The shells in Examples 1-11 all have low densities, meeting the requirements for lightweight shells.

[0113] The shell of Comparative Example 1 is made of injection-molded steel sheet. The density of the steel sheet is too high, which does not meet the requirements for lightweight shell.

[0114] In addition to the tests mentioned above, the process performance of the shells of Examples 1-11 and the shell of Comparative Example 1 was also tested, as detailed in Table 3.

[0115] Table 3 - Comparison of process performance tests of the shells in the examples and comparative examples

[0116] As shown in Table 3, the injection molding yield of the shells in Examples 1-11 is relatively high, reaching 100%. In contrast, the shell in Comparative Example 1 uses insert injection molding to mold steel sheets. Due to the different shrinkage rates of PPA material and steel sheets, shell deformation is easily caused, and cracks are prone to occur between the PPA and the steel sheets. Therefore, the product yield is low, only 75%.

[0117] In summary, the shell in Comparative Example 1 is formed by injection molding steel sheets using an insert injection molding process. The excessive density of the steel sheets results in a large overall weight for the shell, failing to meet the requirements for lightweight design. Furthermore, the different shrinkage rates of the PPA material and the steel sheet in this process easily cause shell deformation and cracking between the PPA and steel sheets, leading to low product yield and failure to meet sealing performance requirements.

[0118] The shells in Examples 1-11 are formed by injection molding of polyamide and carbon fiber materials. The mass ratio of carbon fiber to polyamide is 0.42-1. Carbon fiber can significantly improve the strength and modulus of the polyamide composite material. Moreover, due to the low density of polyamide, the density of the shell is 1.2 g / cm³. 3 -1.45g / cm 3Within this range, a lightweight design of the shell can be achieved. The heat distortion temperature of polyamide is ≥250℃, which ensures minimal strength loss and strong structural stability of the shell during high-temperature operation. Furthermore, the flexural modulus of the shell is in the range of 20GPa-40GPa, which avoids resonance between the shell and the sound-generating monomer 20, reduces the processing difficulty of the shell, minimizes shell defects, and improves product yield. The flexural strength of the shell is in the range of 200MPa-450MPa, making it less prone to deformation under impact and reducing the likelihood of cracking between the steel sheet and the injection-molded material. Moreover, the shells in Examples 1-11 do not require steel sheets, simplifying the processing and resulting in a high product yield.

[0119] The above embodiments mainly describe 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. For the sake of brevity, they will not be elaborated here.

[0120] While specific embodiments of the invention have been described in detail by way of examples, those skilled in the art should understand that the examples are for illustrative purposes only and not intended to limit the scope of the invention. Those skilled in the art should understand that modifications can be made to the above embodiments without departing from the scope and spirit of the invention. The scope of the invention is defined by the appended claims.

Claims

1. A housing for a sound-generating device, characterized in that, The shell includes a reinforcing section with a thickness ≤0.3mm. The reinforcing section is injection molded from a polyamide composite material composed of carbon fiber and polyamide. The mass ratio of the carbon fiber to the polyamide in the reinforcing section is 0.42-1, and the density of the reinforcing section is 1.2g / cm³. 3 -1.45g / cm 3 The bending modulus of the reinforcing part is 20GPa-40GPa.

2. The housing of the sound-generating device according to claim 1, characterized in that, The polyamide includes a semi-aromatic polyamide, which includes at least one of PPA, PA46, PA4T, PA5T, PA6T, PA9T, PA10T, and PA12T.

3. The housing of the sound-generating device according to claim 1, characterized in that, The carbon fiber has a carbon content of 92%-99.99%, and / or the degree of graphitization R of the carbon fiber is 0.8-1.05, and / or the length of the carbon fiber is 0.1mm-1mm, and / or the orientation angle of the graphite crystals of the carbon fiber is ≤25°.

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

5. The housing of the sound-generating device according to claim 1, characterized in that, The housing has an internal cavity, and at least a portion of the cavity wall is formed by the reinforcing portion.

6. The housing of the sound-generating device according to claim 5, characterized in that, The receiving cavity includes a front acoustic cavity and a rear acoustic cavity, and at least a portion of the walls of the front acoustic cavity and / or the rear acoustic cavity are formed by the reinforcing portion.

7. The housing of the sound-generating device according to claim 1, characterized in that, The entire shell is composed of the reinforcing parts.

8. The housing of the sound-generating device according to claim 1, characterized in that, The housing also includes a base portion, which is integrally injection molded with the reinforcing portion.

9. The housing of the sound-generating device according to claim 8, characterized in that, The matrix portion includes a resin material, which 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.

10. The housing of the sound-generating device according to claim 9, characterized in that, The matrix further includes a fiber material, which includes carbon fiber and / or glass fiber, and the resin material is mixed with the fiber material, wherein the mass ratio of the fiber material to the resin material is 0.25-1.

11. The housing of the sound-generating device according to claim 1, characterized in that, The bending strength of the reinforcing part is 200MPa-450MPa; And / or, the heat distortion temperature of the reinforcing part is ≥250℃.

12. A sound-generating device, characterized in that, The housing of the sound-generating device as described in any one of claims 1 to 11.

13. The sound-generating device according to claim 12, characterized in that, The sound-generating device further includes a sound-generating unit disposed within the housing. The sound-generating unit includes a vibration system. Along the vibration direction of the vibration system, at least a portion of the housing opposite to the sound-generating unit is composed of the reinforcing portion.

14. An electronic device, characterized in that, Includes the sound-generating device as described in claim 13.

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