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

Abstract

The utility model discloses a shell of a sounding device, the sounding device and electronic equipment. The shell comprises a reinforcing part, the thickness of the reinforcing part is smaller than or equal to 0.3 mm, the reinforcing part is formed by injection molding of a polyamide composite material composed of carbon fibers and polyamide, in the reinforcing part, the mass ratio of the carbon fibers to the polyamide is 0.42-1, the length of the carbon fibers is 0.1 mm-1 mm, and the bending strength of the reinforcing part is 200 MPa-450 MPa. In the utility model, the shell has high modulus and strength. Moreover, the shell does not need to be thinned by injection molding of a steel sheet, heat conduction and structural strength maintenance, so that the phenomenon of cracking between the steel sheet and an injection molding material is avoided, the processing technology of the shell is simplified, and the product yield is high.

Description

Technical Field

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

[0002] In the related art, the shell of the speaker module is usually made of PC + glass fiber reinforced plastic material and steel sheet inserts. This shell has good structural strength and low price. However, its disadvantage is that the density of the steel sheet insert is too high, for example, the density is 7.8g / cm 3 Excessive density is not conducive to the lightweight requirements of speaker modules and electronic products.

[0003] Furthermore, the joints between the plastic material and the steel insert in the speaker module housing are weak, making waterproofing failure a common problem. The speaker module housing is manufactured using an injection molding process. The different shrinkage rates of the plastic material and the steel insert can easily cause housing deformation, leading to difficulties in housing assembly and speaker module performance failure.

[0004] Therefore, it is necessary to provide a new technical solution to solve the above technical problems. Utility Model Content

[0005] One purpose of the utility model 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 reinforcement portion having a thickness of 0.3 mm or less, the reinforcement 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 reinforcement portion is 0.42-1, the length of the carbon fiber is 0.1 mm-1 mm, and the bending strength of the reinforcement portion is 200 MPa-450 MPa.

[0007] Optionally, the polyamide includes semi-aromatic polyamide, and the semi-aromatic polyamide 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 a graphitization degree R value of the carbon fiber is 0.8-1.05, and / or an orientation angle of graphite crystallites of the carbon fiber is ≤25°.

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

[0010] Optionally, an accommodating cavity is provided inside the shell, and at least a portion of the wall of the accommodating cavity is formed by the reinforcement portion.

[0011] Optionally, the accommodating cavity includes a front acoustic cavity and a rear acoustic cavity, and at least part of the wall of the front acoustic cavity and / or the rear acoustic cavity is formed by the reinforcement portion.

[0012] Optionally, the entire shell is composed of the reinforcement part.

[0013] Optionally, the shell further includes a base portion, and the base portion and the reinforcement portion are integrally injection molded.

[0014] Optionally, the base 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.

[0015] Optionally, the base portion further includes a fiber material, the fiber material includes 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 0.25-1.

[0016] Optionally, the thermal deformation temperature of the reinforcement portion is ≥250°C;

[0017] And / or, the density of the reinforcement is 1.2 g / cm 3 -1.45g / cm 3 ;

[0018] And / or, the bending modulus of the reinforcement portion is 20 GPa-40 GPa.

[0019] 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.

[0020] Optionally, the sound-emitting device further includes a sound-emitting unit disposed in the shell, the sound-emitting unit includes a vibration system, and along the vibration direction of the vibration system, at least a portion of the shell opposite to the sound-emitting unit is composed of the reinforcement portion.

[0021] According to a third aspect of the present invention, an electronic device is provided, which includes the sound-generating device of the present invention.

[0022] In an embodiment of the present invention, the housing of the sound-generating device includes a reinforcement portion, which is formed by injection molding a composite material composed of carbon fiber and polyamide. Due to the high strength and modulus of the polyamide composite material, the thickness of the reinforcement portion can be made thinner while meeting the structural strength requirements of the housing. In the reinforcement portion, the mass ratio of the carbon fiber to the polyamide is 0.42-1. Carbon fiber can significantly improve the strength, modulus, and thermal conductivity of the polyamide composite material. During reliability verification, resonance between the housing and the sound-generating monomer is unlikely to occur, and the housing has good thermal conductivity. The length of the carbon fiber is 0.1mm-1mm. Within this range, the structural strength of the housing is high, and the housing is not prone to problems such as exposed fibers and floating fibers during the injection molding process, resulting in a high product yield. The flexural strength of the housing is 200MPa-450MPa. Within this range, the housing is not easily deformed when impacted, and the processing difficulty of the housing is low, resulting in a high product yield. The housing has a high modulus and strength. In addition, the shell does not require injection-molded steel sheets for thinning, heat conduction, and maintaining structural strength, thereby avoiding cracking between the steel sheet and the injection-molded material, simplifying the shell processing technology, and improving the product yield.

[0023] Other 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 accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

[0025] Figure 1 It is a cross-sectional view of a sound-generating device according to an embodiment of the present utility model.

[0026] Description of reference numerals:

[0027] 10. First shell; 11. Top wall; 111. Front acoustic cavity; 121. Rear acoustic cavity; 15. Side wall edge; 20. Sound unit; 30. PCB; 40. Second shell; 41. Bottom wall. DETAILED DESCRIPTION

[0028] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangements of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention.

[0029] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the present invention, its application, or uses.

[0030] 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 part of the specification.

[0031] 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.

[0032] It should be noted that like reference numerals and letters refer to like items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0033] According to one embodiment of the present invention, a housing for a sound-generating device is provided. The housing includes a reinforcement portion having a thickness of 0.3 mm or less and 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 reinforcement portion is 0.42-1, the length of the carbon fiber is 0.1 mm-1 mm, and the bending strength of the reinforcement portion is 200 MPa-450 MPa.

[0034] Specifically, if Figure 1 As shown, the first housing 10 and the second housing 40 are connected together to form a housing cavity therein. The housing cavity is used to accommodate the sound unit 20 and the PCB 30. The sound unit 20 is connected to the PCB 30. A front acoustic cavity is formed between the first housing 10 and the sound unit 20. 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-emitting device. A rear acoustic cavity is formed between the second housing 40 and the sound unit 20. The rear acoustic cavity can adjust the low-frequency effects of the sound-emitting device. The PCB 30 is connected to the 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 sidewall edges 15 of the first and second side walls are ultrasonically welded or adhesively bonded. Reinforcement portions are provided on at least a portion of the top wall 11, bottom wall 41, first side wall, and second side wall. Furthermore, the top wall 11, bottom wall 41, first side wall, and / or second side wall may all be reinforcement portions. Alternatively, one of the first shell 10 and the second shell 40 may be a flat plate structure. The reinforcement portion is provided on at least a portion of the first shell 10 and the second shell 40 .

[0035] The reinforcement is a polyamide composite material. The polyamide composite material includes carbon fiber and polyamide mixed together. Polyamide, also known as nylon, is a high molecular weight polymer containing repeated amide groups (-NHCO-) ​​in the main chain. It can be produced by reactions such as lactam ring-opening polymerization or diamine and dibasic acid condensation. Polyamide has the characteristics of high strength, high rigidity, high heat resistance and high toughness, which makes the modulus and strength of polyamide polymer high. Carbon fiber is a high-strength, high-modulus high-performance fiber material, which is produced by organic fibers (such as polyacrylonitrile, viscose fiber or asphalt) through carbonization and other processes. Carbon fiber has high strength and modulus in the fiber direction and the density of carbon fiber is lower than that of glass fiber. The carbon fiber reinforced shell structure has better strength effect. Under the condition of meeting the shell strength and modulus requirements, the amount of carbon fiber added to the polyamide composite material is lower, which is conducive to achieving lightweight shell. In addition, the thermal conductivity of carbon fiber is good, which makes the shell have good thermal conductivity, making the strength, modulus and thermal conductivity of the polyamide composite material excellent.

[0036] In this embodiment, due to the high strength and modulus of the polyamide composite material, the thickness of the reinforcement portion can be made thinner while still meeting the structural strength requirements of the housing. The thickness of the reinforcement portion is ≤ 0.3 mm. This thin reinforcement portion allows for greater space within the housing, increasing the volume of the front and / or rear acoustic cavities, and thus enabling more effective adjustment of the sound effects of the sound-generating device.

[0037] The mass ratio of the carbon fiber to the polyamide is 0.42-1. When the mass ratio of the carbon fiber to the polyamide is greater than 1, the high density of the carbon fibers in the polyamide composite material results in excessively high viscosity, making it susceptible to glue shortages during the injection molding process. Conversely, when the mass ratio of the carbon fiber to the polyamide is less than 0.42, the carbon fibers' reinforcing effect on the polyamide composite material is poor, and the housing is susceptible to resonance at mid-frequency levels during the reliability verification of the sound-generating device, resulting in excessively high THD distortion in the mid-frequency range. When the mass ratio of the carbon fiber to the polyamide is 0.42-1, glue shortages are less likely to occur during the injection molding process, and the housing exhibits 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. 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 modulus and strength of the polyamide composite material are high.

[0038] 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 carbon fiber length 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 structural 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 structural strength of the shell high, and the shell is not prone to problems such as exposed fibers and floating fibers during the injection molding process.

[0039] The bending strength of the shell is 200MPa-450MPa. 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 less than 200MPa, the shell is prone to deformation or even breakage when impacted; when the bending strength is greater than 450MPa, the shell has poor fluidity during injection molding and is difficult to process. In this embodiment, the bending strength of the shell is 200MPa-450MPa. Within this range, the shell is not easily deformed when impacted, and the processing difficulty of the shell is low, and the product yield is high. Optionally, the bending strength of the shell is 200MPa, 250MPa, 300MPa, 350MPa, 400MPa, 450MPa, etc. The above values ​​all make the shell have excellent impact resistance and low processing difficulty, and the product yield is high.

[0040] The preparation process of the housing of the present invention may include:

[0041] (1) Preparation of polyamide composite materials. Polyamide is fed into a twin-screw extruder from the main feed port and melted. After the polyamide is melted, carbon fiber is added from the side feed port. The carbon fiber and the molten polyamide are shear-mixed in the extruder and then extruded into pellets.

[0042] (2) Preparation of Shells The granulated polyamide 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 .

[0043] (3) Assemble the sound unit 20, PCB 30 and other components into the accommodation cavity formed by the first shell 10 and the second shell 40. Then, align the two side wall edges 15 of the first shell 10 and the second shell 40 and perform ultrasonic welding or bonding to connect the two side wall edges 15 together.

[0044] 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 polyamide is melted. This can effectively reduce the damage of the carbon fiber during the mixing process, thereby improving the reinforcement effect of carbon fiber on polyamide composite materials.

[0045] In an embodiment of the present invention, the housing of the sound-generating device includes a reinforcement portion, which is formed by injection molding a composite material composed of carbon fiber and polyamide. Due to the high strength and modulus of the polyamide composite material, the thickness of the reinforcement portion can be made thinner while meeting the structural strength requirements of the housing. In the reinforcement portion, the mass ratio of the carbon fiber to the polyamide is 0.42-1. The carbon fiber significantly improves the strength, modulus, and thermal conductivity of the polyamide composite material. During reliability verification, resonance between the housing and the sound-generating unit 20 is less likely to occur, and the housing has good thermal conductivity. The length of the carbon fiber is 0.1mm-1mm. Within this range, the structural strength of the housing is high, and the housing is less likely to have problems such as exposed fibers or floating fibers during the injection molding process, resulting in a high product yield. The flexural strength of the housing is 200MPa-450MPa. Within this range, the housing is less likely to deform when impacted, and the processing difficulty of the housing is low, resulting in a high product yield. The housing has a high modulus and strength. In addition, the shell does not require injection-molded steel sheets for thinning, heat conduction, and maintaining structural strength, thereby avoiding cracking between the steel sheet and the injection-molded material, simplifying the shell processing technology, and improving the product yield.

[0046] In a specific embodiment of the present invention, the polyamide includes semi-aromatic polyamide, and the semi-aromatic polyamide includes at least one of PPA, PA46, PA4T, PA5T, PA6T, PA9T, PA10T, and PA12T.

[0047] Semi-aromatic polyamides are polymer materials produced through the polycondensation reaction of aliphatic diamines or dibasic acids with aromatic dibasic acids or diamines. Semi-aromatic polyamides exhibit excellent high-temperature resistance and a high initial modulus, resulting in polyamide composites with increased stiffness, modulus, and improved high-temperature resistance. Optionally, the semi-aromatic polyamide comprises at least one of PPA, PA46, PA4T, PA5T, PA6T, PA9T, PA10T, and PA12T. In other words, any one of the aforementioned semi-aromatic polyamides can be selected, or a mixture of at least two of these can be selected.

[0048] In a specific embodiment of the present invention, the carbon content of the carbon fiber is 92%-99.99%, and / or the graphitization degree R value of the carbon fiber is 0.8-1.05, and / or the orientation angle of the graphite crystallites of the carbon fiber is ≤25°.

[0049] 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 92%-99.99%. Within the range, under the same mass content conditions, the modulus of the polyamide composite material is high, and the structural strength of the shell as a whole is high. Optionally, the carbon content of the carbon fiber is 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99.99%, etc. The above values ​​can all make the modulus and strength of the polyamide composite material high, and the structural strength of the shell as a whole high.

[0050] The orientation angle of graphite crystallites refers to the angle between the crystal plane of graphite crystallites and the fiber direction. The smaller the orientation angle of graphite crystallites in carbon fiber, the higher the modulus in the fiber direction, and the higher the lifting effect on the modulus of the polyamide composite material. In this embodiment, the orientation angle of graphite crystallites in carbon fiber is ≤25 °. Within this range, the modulus of carbon fiber in the fiber direction is high, so that the modulus of polyamide composite material is high. Optionally, the orientation angle of graphite crystallites in carbon fiber is 15 °, 17 °, 19 °, 20 °, 22 °, 24 °, 25 °, etc. The above values ​​all make the modulus of polyamide composite material high.

[0051] In other embodiments, the carbon fibers meet at least two of the above conditions. The polyamide composite material has high modulus and strength and is less prone to problems such as exposed fibers and floating fibers.

[0052] 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 polyamide sizing agent, a polyurethane sizing agent, and an epoxy resin sizing agent.

[0053] In this embodiment, the surface of carbon fiber has inertia, poor compatibility with polyamide, and low bonding strength. In the polyamide composite material preparation process, it is necessary to carry out surface treatment on the surface of carbon fiber to improve the compatibility of carbon fiber and polyamide. Carbon fiber is sizing treated using a sizing agent. Sizing agent includes at least one of polyamide sizing agent, polyurethane sizing agent, and epoxy resin sizing agent. Above-mentioned sizing agent can all promote the bonding strength of carbon fiber and polyamide, improve the compatibility of carbon fiber and polyamide.

[0054] In a specific embodiment of the present invention, an accommodating cavity is provided inside the shell, and at least a part of the wall of the accommodating cavity is formed by the reinforcement portion.

[0055] like Figure 1As shown, the first shell 10 and the second shell 40 are connected to form a accommodating chamber inside the shell. A sound-emitting unit 20 and a PCB 030 are arranged in the accommodating chamber. The wall portion of the accommodating chamber includes 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 side wall and the second side wall are ultrasonically welded or adhesively bonded. A reinforcement portion is provided on at least a portion of the top wall 11, the bottom wall 41, the first side wall and / or the second side wall. This arrangement can significantly increase the volume of the accommodating chamber, thereby being able to more effectively adjust the sound effect of the sound-emitting device.

[0056] In a specific embodiment of the present invention, the cavity includes a front acoustic cavity and a rear acoustic cavity, and at least part of the wall of the front acoustic cavity and / or the rear acoustic cavity is formed by the reinforcement part.

[0057] like Figure 1 As shown, a front sound cavity is formed between the first shell 10 and the sound-emitting unit 20, and the front sound cavity has a sound outlet. The sound outlet is used to radiate sound waves outward. The front sound cavity can adjust the mid- and high-frequency effects of the sound-emitting device. A rear sound cavity is formed between the second shell 40 and the sound-emitting unit 20. The rear sound cavity can adjust the low-frequency effect of the sound-emitting device. In this embodiment, at least a portion of the wall of the front sound cavity (e.g., the top wall 11 and the first side wall) or the wall of the rear sound cavity (e.g., the bottom wall 41 and the second side wall) is formed by a reinforcement; or at least a portion of the wall of the front sound cavity (e.g., the top wall 11 and the first side wall) and the wall of the rear sound cavity (e.g., the bottom wall 41 and the second side wall) is formed by a reinforcement. Since the thickness of the reinforcement is relatively small, the volume of the front sound cavity and / or the rear sound cavity can be effectively increased, thereby improving the sound effect of the sound-emitting device.

[0058] In a specific embodiment of the present invention, the entire housing is composed of the reinforcement portion.

[0059] In other words, in this embodiment, the first shell 10 and / or the second shell 40 are all made of a polyamide composite material by integral injection molding, and the polyamide composite material includes a mixture of polyamide and carbon fiber, the thickness of the reinforcement portion is ≤0.3 mm, and the mass ratio of the carbon fiber to the polyamide is 0.42-1. 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 made of a polyamide composite material by integral injection molding, and part of the structure of the second shell 40 is also made of a polyamide composite material by integral injection molding; or, part of the structure of the first shell 10 is made of a polyamide composite material by integral injection molding, and the second shell 40 is entirely made of a polyamide composite material by integral injection molding; or, both the first shell 10 and the second shell 40 are entirely made of a polyamide composite material by integral injection molding.

[0060] In a specific embodiment of the present invention, the shell further includes a base portion, and the base portion and the reinforcement portion are integrally injection molded.

[0061] Specifically, if Figure 1 As shown, for the first shell 10, the reinforcement portion is located on the top wall 11, and the first side wall includes the base portion; or the reinforcement portion is located on the first side wall, and the top wall 11 includes the base portion. For the second shell 40, the reinforcement portion is located on the bottom wall 41. The second side wall includes the base portion; or the reinforcement 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 shot, and the reinforcement portion is formed on the base portion in a second shot. After curing, the base portion and the reinforcement portion are connected together. In this embodiment, the base portion and the reinforcement portion can be processed into a set shape according to actual needs to meet the sound requirements of different sound-emitting devices. In this arrangement, different parts of the first shell 10 and / or the second shell 40 can be made of different materials according to different functions. 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.

[0062] In a specific embodiment of the present invention, the base 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.

[0063] When preparing the base part, 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.

[0064] In a specific embodiment of the present invention, the base portion further includes a fiber material, the fiber material includes 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 0.25-1.

[0065] 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 polyamide composite material, and the fiber material can significantly improve the modulus and strength of the polyamide composite material. When the mass ratio of the fiber material to the resin material is less than 0.25, the fiber material has little effect on the modulus and strength of the polyamide composite material; conversely, when the mass ratio of the fiber material to the resin material is greater than 1, the density of the formed polyamide composite material is large, which does not meet the requirements for lightweight shell. 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 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 0.25, 0.30, 0.40, 0.50, 0.60, 0.70, 0.8, 0.9, 1, etc., and the above values ​​all make the polyamide composite material have both high strength and modulus and the mass of the shell formed is light.

[0066] In a specific embodiment of the present invention, the thermal deformation temperature of the reinforcement portion is ≥250°C.

[0067] 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 likely it is that the shell can maintain structural stability under higher conditions. In this embodiment, the heat deformation temperature of the shell is ≥250°C, so that the shell has strong high temperature resistance and is not easily deformed during high temperature and high humidity reliability and high power reliability verification. Optionally, the heat deformation temperature of the shell is 250°C, 260°C, 270°C, 300°C, 320°C, 330°C, 350°C, etc. The above values ​​all make the shell have strong high temperature resistance and are not easily deformed during high temperature and high humidity reliability and high power reliability verification.

[0068] In a specific embodiment of the present invention, the density of the reinforcement portion is 1.2 g / cm 3 -1.45g / cm 3 .

[0069] Since the density of polyamide is relatively low, the density of the reinforcement is less than 1.2g / cm after being compounded with carbon fiber. 3 When the content of carbon fiber in the polyamide composite material is too high, it is easy to cause the shell to be short of glue during the injection molding process; on the contrary, the density of the reinforcement part is greater than 1.45g / cm 3 When the shell is too heavy, it is easy to cause the shell to be too heavy, which does not meet the requirement of lightweight shell. In this embodiment, the density of the reinforcement part is 1.2g / cm 3 -1.45g / cm 3 Within this range, the shell has few defects and meets the requirements of lightweight shell. Optionally, the density of the reinforcement part is 1.2g / cm 3, 1.25g / cm 3 , 1.3g / cm 3 , 1.35g / cm 3 , 1.4g / cm 3 , 1.45g / cm 3 The above values ​​can reduce the defects of the shell and meet the requirements of lightweight shell.

[0070] In a specific embodiment of the present invention, the bending modulus of the reinforcement portion is 20 GPa-40 GPa.

[0071] 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, <20GPa, the shell is prone to local vibration, which is easy to resonate with the vibration of the sound-emitting unit 20, resulting in poor sound effect of the sound-emitting device; if the bending modulus of the shell is too high, for example, >40GPa, it will increase the difficulty of processing the shell and reduce the product yield. For example, when using a polyamide composite material to prepare a shell, it is necessary to increase the amount of carbon fiber added. For example, if the mass ratio of carbon fiber to polyamide is greater than 1, the viscosity of the polyamide melt will be too high, and fiber exposure and glue deficiency will easily occur during the injection molding process. In this embodiment, the bending modulus of the shell is 20GPa-40GPa. Within this range, it can avoid the resonance between the shell and the sound-emitting unit 20, reduce the difficulty of processing the shell, reduce shell defects, and improve product yield. In addition, due to the large bending modulus of the reinforcement, the reinforcement can be made thinner, for example, with a thickness of ≤0.3mm, thereby increasing the volume of the accommodating cavity and providing sufficient structural strength for the shell, eliminating the need to increase the strength of the shell by injection molding steel sheets, which simplifies the shell processing process. Optionally, the bending modulus of the shell can be 20GPa, 25GPa, 30GPa, 35GPa, 40GPa, etc. The above values ​​can avoid resonance between the shell and the sound unit 20, reduce the difficulty of shell processing, and improve product yield.

[0072] In a specific embodiment of the present invention, the thermal deformation temperature of the shell is ≥250°C; and / or the density of the reinforcement is 1.2g / cm 3 -1.45g / cm 3 and / or the flexural modulus of the reinforcement is 20 GPa to 40 GPa. In other words, the housing's performance satisfies at least two of the above conditions. This significantly improves the housing's deformation resistance and high-temperature resistance, while also minimizing processing complexity.

[0073] 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.

[0074] like Figure 1As 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 the external circuit. The edges of the first shell 10 and the second shell 40 are both provided with side wall edges 15. The side wall edges 15 of the first shell 10 and the second shell 40 are connected together by ultrasonic welding or glue.

[0075] The sound-generating device has the characteristics of high structural strength, good high-temperature resistance and good sound effect.

[0076] In a specific embodiment of the present invention, the sound-emitting device also includes a sound-emitting unit arranged in the shell, and the sound-emitting unit includes a vibration system. Along the vibration direction of the vibration system, at least a part of the shell opposite to the sound-emitting unit is composed of the reinforcement part.

[0077] like Figure 1 As shown, the interior of the housing forms a front sound cavity 111 and a rear sound cavity 121. The sound-emitting unit is located between the front sound cavity 111 and the rear sound cavity 121. The front sound cavity 111 has a sound outlet. The sound outlet is used to radiate sound waves outward. The sound-emitting unit 20 includes a vibration system. The vibration direction of the vibration system is as shown in FIG. Figure 1 Indicated by the middle arrow. Along the vibration direction of the vibration system, at least a portion of the housing that faces the sound-producing unit is, for example, at least a portion of the top wall 11 or at least a portion of the bottom wall 41; alternatively, it may be at least a portion of both the top wall 11 and the bottom wall 41. When the reinforcement is located on the top wall 11, due to its relatively thin thickness (e.g., ≤0.3mm), the front acoustic cavity 111 is larger along the vibration direction for the same housing dimensions, thereby allowing the vibration amplitude of the sound-producing unit's vibration system to be greater, thereby enhancing the sound quality of the sound-producing device. When the reinforcement is located on the bottom wall 41, the rear acoustic cavity 121 is larger along the vibration direction, allowing the vibrating airflow to more rapidly adsorb and desorb within the rear acoustic cavity 121, thereby enhancing the low-frequency performance of the sound-producing device. Alternatively, the reinforcement can be located on both the top wall 11 and the bottom wall 41, allowing the sound-producing device to combine both of these advantages, resulting in even better sound quality.

[0078] According to a third embodiment of the present invention, an electronic device is provided. The electronic device includes the sound-generating device described in the present invention. The electronic device has excellent durability. Optionally, the electronic device is a computer, a mobile phone, a watch, a television, a speaker, an AR device, a VR device, a vehicle, etc.

[0079] 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 merely exemplary and does not specifically limit the present invention.

[0080] Comparative Example 1

[0081] The shell is formed by insert injection molding using steel sheets and PPA materials, the insert is located on the top wall 11, and the obtained shell is assembled with the sound-emitting monomer 20 to obtain a sound-emitting device.

[0082] Example 1

[0083] The shell is formed by injection molding using 70 wt% PPA material and 30 wt% carbon fiber, with the reinforcement portion located on the top wall 11 , and the obtained shell is assembled with the sound-generating monomer 20 to obtain a sound-generating device.

[0084] Example 2

[0085] A shell is formed by injection molding using 65wt% PPA material and 35wt% carbon fiber, with the reinforcement portion located on the top wall 11 . The obtained shell is assembled with the sound-generating monomer 20 to obtain a sound-generating device.

[0086] Example 3

[0087] A shell is formed by injection molding using 60 wt% PPA material and 40 wt% carbon fiber, with the reinforcement portion located on the top wall 11 . The obtained shell is assembled with the sound-generating monomer 20 to obtain a sound-generating device.

[0088] Example 4

[0089] A shell is formed by injection molding using 55wt% PPA material and 45wt% carbon fiber, with the reinforcement portion located on the top wall 11 . The obtained shell is assembled with the sound-generating monomer 20 to obtain a sound-generating device.

[0090] Example 5

[0091] A shell is formed by injection molding using 50 wt% PPA material and 50 wt% carbon fiber, with the reinforcement portion located on the top wall 11 , and the obtained shell is assembled with the sound-generating monomer 20 to obtain a sound-generating device.

[0092] Example 6

[0093] A shell is formed by injection molding using 65wt% PA4T and 35wt% carbon fiber, with the reinforcement portion located on the top wall 11 . The obtained shell is assembled with the sound-generating monomer 20 to obtain a sound-generating device.

[0094] Example 7

[0095] A shell is formed by injection molding using 60wt% PA5T and 40wt% carbon fiber, with the reinforcement portion located on the top wall 11 . The obtained shell is assembled with the sound-generating monomer 20 to obtain a sound-generating device.

[0096] Example 8

[0097] A shell is formed by injection molding using 55wt% PA6T and 45wt% carbon fiber, with the reinforcement portion located on the top wall 11 . The obtained shell is assembled with the sound-generating monomer 20 to obtain a sound-generating device.

[0098] Example 9

[0099] A shell is formed by injection molding using 60wt% PA9T and 40wt% carbon fiber, with the reinforcement portion located on the top wall 11 . The obtained shell is assembled with the sound-generating monomer 20 to obtain a sound-generating device.

[0100] Example 10

[0101] A shell is formed by injection molding using 65wt% PA10T and 35wt% carbon fiber, with the reinforcement portion located on the top wall 11 . The obtained shell is assembled with the sound-generating monomer 20 to obtain a sound-generating device.

[0102] Example 11

[0103] A shell is formed by injection molding using 55wt% PA12T and 45wt% carbon fiber, with the reinforcement portion located on the top wall 11 . The obtained shell is assembled with the sound-generating monomer 20 to obtain a sound-generating device.

[0104] It should be noted that the outer dimensions of the housings in the comparative example and the examples are consistent. For ease of comparison, the raw material proportions of comparative example 1 and examples 1-11 are shown in Table 1.

[0105] Table 1 - Raw material ratios of the shells of the embodiments and comparative examples

[0106]

[0107] The steel sheet of comparative example 1 and the shells of embodiments 1-11 were tested for thermal deformation temperature, density, bending modulus, and bending strength, respectively. The test results are shown in Tables 2 and 3.

[0108] The test conditions and standards are as follows:

[0109] (1) Flexural modulus and flexural strength test: The test shall be conducted in accordance with GB / T 9341-2008, Determination of Flexural Properties of Plastics.

[0110] (2) Heat deformation temperature test: The test shall be carried out in accordance with GB / T 1634.2-2004 Plastics - Determination of heat deformation temperature - Part 2: Plastics, hard rubber and long fiber reinforced polyamide composites.

[0111] (3) Density test method: The test shall be carried out 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, and the immersion method shall be used for testing.

[0112] Table 2 - Performance test comparison of the shell of the embodiment and the steel sheet of the comparative example

[0113]

[0114]

[0115] As shown in Table 2, the heat deformation temperatures of the shells of Examples 1-11 are all ≥270°C. The flexural strengths of the shells of Examples 1-11 are all between 200 MPa and 450 MPa. The flexural strength of the steel sheet of Comparative Example 1 is 500 MPa. The flexural modulus of the shells of Examples 1-11 is all between 20 GPa and 40 GPa. The flexural modulus of the steel sheet of Comparative Example 1 is 195 GPa.

[0116] In addition, the density of the shells of Examples 1-11 is all 1.2 g / cm 3 -1.45g / cm 3 The density of the steel sheets in Comparative Example 1 is ≥7.93 g / cm 3 , this density does not meet the requirements of lightweight shell.

[0117] It can be seen that the shell of Example 1-11 is made of a polyamide composite material by injection molding. The polyamide composite material includes carbon fiber and polyamide mixed together. The mass ratio of the carbon fiber to the polyamide is 0.42-1. The density of the reinforcement is 1.2 g / cm 3 -1.45g / cm 3 The flexural modulus of the reinforcement is 20 GPa-40 GPa, and the thickness of the reinforcement is ≤0.3 mm. This results in high thermal deformation temperature, flexural modulus, and flexural strength for the housings of Examples 1-11. This indicates that the housings have high structural strength, minimal strength loss during high-temperature operation, and strong structural stability. The housings of Examples 1-11 all have low densities, meeting the requirements for lightweight housings.

[0118] The shell of Comparative Example 1 is made of injection-molded steel sheet, but the density of the steel sheet is too high and does not meet the requirement of lightweight shell.

[0119] In addition to the above tests, the process performance of the shells of Examples 1-11 and the shell of Comparative Example 1 was also tested, as shown in Table 3 for details.

[0120] Table 3 - Comparison of process performance tests of the shells of the embodiment and the comparative example

[0121]

[0122]

[0123] As shown in Table 3, the injection molding yields of the housings of Examples 1-11 were all high, reaching 100%. In contrast, the housing of Comparative Example 1 was formed using an insert molding process using steel sheets. Due to the different shrinkage rates of the PPA material and the steel sheet, this easily caused housing deformation and cracking between the PPA and the steel sheet. Consequently, the product yield was low, at only 75%.

[0124] In summary, the housing of Comparative Example 1 was formed using an insert molding process with steel sheets. The excessive density of the steel sheets resulted in a heavy overall housing mass, failing to meet lightweight requirements. Furthermore, this process resulted in different shrinkage rates between the PPA material and the steel sheets, which easily caused housing deformation and cracking between the PPA and steel sheets. This resulted in a low product yield and failed to meet sealing performance requirements.

[0125] The shell of Example 1-11 is formed by injection molding 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 polyamide composite materials. Moreover, due to the low density of polyamide, the density of the shell is 1.2g / cm 3 -1.45g / cm 3 range, thereby achieving a lightweight design of the shell. The heat deformation temperature of polyamide is ≥250°C, which can minimize the decrease in strength of the shell during high-temperature operation and enhance structural stability. In addition, the bending modulus of the shell is in the range of 20GPa-40GPa, which can not only avoid resonance between the shell and the sound-emitting 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 200MPa-450MPa, and the shell is not easily deformed when impacted, and cracking is not easy between the steel sheet and the injection molding material. In addition, the shells of Examples 1-11 do not require steel sheets, the processing technology is simple, and the product yield is high.

[0126] 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.

[0127] Although some specific embodiments of the present invention have been described in detail through examples, those skilled in the art will appreciate that the above examples are for illustration only and are not intended to limit the scope of the present invention. Those skilled in the art will appreciate that modifications may be made to the above embodiments 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 shell includes a reinforcement portion, the thickness of the reinforcement portion is ≤0.3mm, the reinforcement portion is formed by injection molding of a polyamide composite material consisting of carbon fiber and polyamide, the length of the carbon fiber in the reinforcement portion is 0.1mm-1mm, and the bending strength of the reinforcement portion is 200MPa-450MPa.

2. The housing of the sound-generating device according to claim 1, wherein: The polyamide includes semi-aromatic polyamide, and the semi-aromatic polyamide includes any one of PPA, PA46, PA4T, PA5T, PA6T, PA9T, PA10T, and PA12T.

3. The housing of the sound-generating device according to claim 1, wherein: The orientation angle of the graphite crystallites of the carbon fiber is ≤25°.

4. The housing of the sound-generating device according to claim 1, wherein: The carbon fibers are sizing-treated with a sizing agent, wherein the sizing agent comprises any one of a polyamide sizing agent, a polyurethane sizing agent, and an epoxy resin sizing agent.

5. The housing of the sound-generating device according to claim 1, wherein: An accommodating cavity is provided inside the shell, and at least a portion of a wall of the accommodating cavity is formed by the reinforcement portion.

6. The housing of the sound-generating device according to claim 5, characterized in that: The accommodating 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 reinforcement portion.

7. The housing of the sound-generating device according to claim 1, wherein: The entire shell is composed of the reinforcement part.

8. The housing of the sound-generating device according to claim 1, wherein: The shell further includes a base portion, and the base portion and the reinforcement portion are integrally injection-molded.

9. The housing of the sound-generating device according to claim 8, characterized in that: The base portion includes a resin material, and the resin material includes any 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 base portion further comprises a fiber material, wherein the fiber material comprises carbon fiber and / or glass fiber.

11. The housing of the sound-generating device according to claim 1, characterized in that: The thermal deformation temperature of the reinforcement portion is ≥250°C; And / or, the density of the reinforcement is 1.2 g / cm 3 -1.45g / cm 3 ; And / or, the bending modulus of the reinforcement portion is 20 GPa-40 GPa.

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

13. The sound generating device according to claim 12, characterized in that: The sound-emitting device further includes a sound-emitting unit disposed in the shell, the sound-emitting unit includes a vibration system, and along the vibration direction of the vibration system, at least a portion of the shell opposite to the sound-emitting unit is composed of the reinforcement portion.

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

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