Preparation process of FPC-containing ear clip for ear clip type earphone

Abstract

The invention relates to the technical field of ear clip type earphone processing, and relates to a preparation process of an FPC-containing ear clip for an ear clip type earphone, and the preparation process comprises the following preparation steps: S1, preparing a memory steel wire, and bending the steel wire into a required shape according to needs to obtain a bent memory steel wire; s2, the bent memory steel wire is placed in a mold, and SR buckles with FPC holes are formed at the two ends of the bent memory steel wire through an SR forming technology; s3, soaking a false steel wire into the silicone oil liquid, penetrating the soaked false steel wire into one FPC hole, and penetrating the soaked false steel wire out of the other hole, so that the false steel wire is parallel to the bent memory steel wire to obtain a frame; s4, the frame is put into a mold for injection molding, so that the upper half parts of the SR buckles, the bent memory steel wires and the false penetrating steel wires are all wrapped by plastic, a first wrapping layer is formed, and a semi-finished product is obtained; and S5, the semi-finished product is put into a mold for injection molding, the surface of the first layer of plastic is wrapped with a layer of plastic to form a second wrapping layer, then the fake steel wire is drawn away to form a channel, the FPC is put into the channel, and a finished product is obtained.

Description

Technical Field

[0001] The present application relates to the technical field of ear clip type earphone processing, and more specifically, to a preparation process of an FPC ear clip for an ear clip type earphone. Background Art

[0002] Ear clip earphones are fixed by clipping above the ear. They do not need to be inserted into the ear canal or cover the entire ear. They will not put pressure on the ear and will not feel uncomfortable when worn for a long time.

[0003] Ear clip headphones mainly include an ear tip for transmitting audio to the ear, an ear clip for fixing the earphone, and a control head for functions such as volume control, play / pause, answer / hang up the phone, and an ear tail for improving the wearing stability of the earphone by contacting the inner side of the earlobe when worn. The ear tip and ear tail are located at the two ends of the ear clip respectively.

[0004] Traditional clip-on earphones mostly rely on wires for signal and power transmission. However, as users' demands for earphone functions grow, more wires are required. The more wires there are, the more difficult it is to align the wires, the more complicated the connection process is, and the more time-consuming it is. At the same time, it will also cause the ear-clip earphones to be larger in size, affecting their use.

[0005] Flexible Printed Circuit (FPC) is a printed circuit made of a flexible insulating substrate. It is thin, soft and flexible. It can connect various components without increasing the size of the ear clip headphones, which helps to miniaturize and lighten the ear clip headphones. At the same time, it fundamentally solves the problems of more wires making it more difficult to align the wires, more complicated connection procedures and more time-consuming.

[0006] In the prior art, the FPC is usually installed in the ear clip to achieve the signal transmission or power supply function between the ear tip and the ear tail. However, in the existing ear clip type headphones, the FPC is completely fixed to the ear clip by glue. During the clamping process, the structure of the ear clip will be deformed to a certain extent. At this time, the change of the ear clip will cause a certain degree of pulling on the FPC. Therefore, after repeated use, the structure of the FPC may be damaged, which is easy to affect the service life of the FPC. At the same time, it may cause the FPC to fall off, thereby affecting the service life of the headphones. Summary of the invention

[0007] In order to solve the problem that the FPC structure is easily damaged and falls off after repeated use, the application provides a preparation process for an FPC ear clip for ear clip type headphones.

[0008] In a first aspect, the present application provides a preparation process for an ear clip containing FPC for an ear clip-type earphone, using the following technical solution: A preparation process for an ear clip containing FPC for an ear clip type earphone, comprising the following preparation steps: S1. Prepare a memory steel wire, and bend the steel wire into a desired shape as required to obtain a curved memory steel wire; S2, placing the bending memory steel wire in a mold, and forming SR buckles with FPC holes at both ends of the bending memory steel ring through an SR molding process; S3, soaking the fake steel wire in silicone oil, and then passing the soaked fake steel wire through one of the FPC holes, and then passing it out through another hole, so that the fake steel wire is parallel to the bending memory steel wire, and a frame is obtained; S4, placing the frame into a mold for injection molding, so that the upper part of the SR buckle, the bending memory steel wire and the fake steel wire are all wrapped by plastic to form a first wrapping layer, and a semi-finished product is obtained; S5. Put the semi-finished product into the mold for injection molding, wrap a layer of plastic on the surface of the first layer of plastic to form a second wrapping layer, then remove the fake steel wire to form a channel, and then place the FPC in the channel to obtain the finished product.

[0009] By adopting the above technical solution, through the process steps of memory steel wire, SR buckle, fake steel wire and double-layer injection molding, the stable fixation and effective protection of FPC in the ear clip are achieved, which not only improves the service life of FPC, but also ensures the stability and reliability of the earphones during long-term use.

[0010] In step S1, the memory steel wire is bent into a desired shape according to the design requirements of the ear clip. This step ensures that the memory steel wire can maintain a stable bending shape in subsequent processes, providing the necessary support and elasticity for the ear clip.

[0011] Step S2: SR buckles with FPC holes are formed at both ends of the memory steel wire through the SR forming process. The SR buckles have good elasticity and toughness, and can adapt to the deformation that may occur during the use of the ear clip, while ensuring the position and shape of the FPC hole are stable, providing a reliable support point for the fixation of the FPC. At the same time, it is also convenient for the SR buckle to be connected with the ear head and ear tail, effectively preventing the FPC from being pulled or falling off.

[0012] The fake steel wire plays an auxiliary role in forming a channel during the injection molding process. It ensures that the channels between the FPC holes are unobstructed, which facilitates the subsequent FPC installation. The temperature is high during the subsequent injection molding process, which can easily damage the FPC and increase defective products. In this application, the fake steel wire is first injected and then removed to reserve a special channel for the FPC to reduce the impact of high temperature. Silicone oil can prevent the fake steel wire from bonding to the first wrapping layer and prevent the fake steel wire from being unable to be removed.

[0013] Steps S4 and S5 use a double-layer injection molding process to form two layers of plastic wrapping on the basis of the memory steel wire and the SR buckle. These two layers of plastic wrapping not only enhance the overall strength and stability, but also provide additional protection for the FPC. Even under the action of external force, the plastic wrapping layer can absorb part of the impact force and reduce damage to the FPC.

[0014] At the final stage of step S5, the FPC is precisely placed into the channel. Since the shape and position of the channel have been precisely controlled through the previous process steps, the FPC can be stably fixed in the ear clip, avoiding pulling and damage caused by deformation of the ear clip.

[0015] Preferably, the injection molding material used in step S2 is composed of LSR silicone, coupling agent, filler and polyethylene in a weight ratio of 10:0.5:5:(2-3).

[0016] By adopting the above technical solution, the toughness and hardness of the SR buckle are further improved, and the SR buckle is prevented from deformation or cracking during use. LSR silicone can form a soft and tough plastic layer to provide support for the memory steel wire and FPC, which is beneficial to increase the stability of the ear clip structure. The coupling agent can enhance the bonding force between LSR silicone and components such as fillers and polyethylene, and improve the overall strength and stability of the material. The filler can increase the density and hardness of the SR buckle, and improve the strength and wear resistance of the ear clip. Polyethylene can form a close bond with other components, improve the overall toughness and impact resistance of the SR buckle, and extend the service life of the ear clip.

[0017] Preferably, the injection molding material used in step S4 is composed of TPU, silane coupling agent, ethylene-vinyl acetate copolymer, filler and polyethylene in a weight ratio of 10:1:5:4:(2-3).

[0018] By adopting the above technical solution, the prepared first wrapping layer has good elasticity and toughness, can withstand greater external force and deformation, and protect the FPC from damage. As the main injection molding material, TPU has excellent elasticity, wear resistance and tear resistance. When combined with other components such as silane coupling agent, EVA and PE, it can improve the strength and toughness of the injection molded parts, enabling them to withstand greater external force and deformation. In the event of an accidental fall or collision, the high-hardness first wrapping layer can better protect the internal electronic components and structures and reduce the risk of damage.

[0019] Preferably, the injection molding material used in step S5 is composed of TPU, SEBS, silane coupling agent, ethylene-vinyl acetate copolymer, antioxidant, filler and polyethylene in a weight ratio of 15:8:1:5:0.1:4:(2-3).

[0020] By adopting the above technical solution, the prepared second wrapping layer has good elasticity, toughness and softness, and the second wrapping layer can absorb most of the impact force and protect the FPC. At the same time, the second wrapping layer is in direct contact with the ear, and the good softness can ensure that when wearing headphones, the pressure and discomfort of the ear clip on the skin during the clamping process can be reduced. In addition, most of the components of the second wrapping layer are the same as those of the first wrapping layer. According to the principle of similar compatibility, the first wrapping layer and the second wrapping layer can be stably connected and will not separate after multiple bending.

[0021] Preferably, the hardness of the first wrapping layer is greater than the hardness of the second wrapping layer.

[0022] By adopting the above technical solution, the stability of the ear clip structure is further improved, the wearing comfort and durability are enhanced. As the layer in direct contact with the ear clip structure, the first wrapping layer has a higher hardness and can provide better support to ensure that the ear clip maintains a stable shape and performance during use. Materials with higher hardness usually have better compression and deformation resistance, and can resist deformation under external forces, thereby protecting key components such as the internal FPC and memory steel wire. At the same time, a certain degree of deformation will occur during the clamping process, and the high hardness of the first wrapping layer can reduce this deformation, reduce the pulling and stress concentration on the FPC, and extend the service life of the FPC. As the layer in direct contact with the user's skin, the second wrapping layer has a lower hardness and can provide better cushioning and shock absorption effects, reducing the pressure and discomfort of the ear clip on the skin during the clamping process. Soft materials can better fit the user's ear contour and improve wearing comfort and stability.

[0023] Preferably, the injection molding process in step S2 is as follows: The first stage: temperature is 110-115℃, injection pressure is 70-75MPa, injection speed is 20-23mm 3 / s, time is 15-20s; second stage: temperature is 115-120℃, injection pressure is 60-65MPa, injection speed is 25-30mm 3 / s, time is 20-30s; The third stage: the temperature is 110-120℃, the injection pressure is 45-50MPa, and the injection speed is 15-20mm 3 / s, time is 25-30s.

[0024] By adopting the above technical solution and accurately controlling the injection molding parameters, product quality problems caused by defects such as insufficient filling, bubbles, and shrinkage holes can be reduced. At the same time, the two-stage injection molding process ensures that the material is fully filled and compacted in the mold, thereby improving the structural strength and durability of the ear clip.

[0025] Preferably, in step S4, the injection molding temperature is 200-220° C., the pressure is 50-60 MPa, the time is 4-6 min, the injection speed is 20-30 mm / s, and the injection position is 60-70 mm.

[0026] Preferably, the injection molding process in step S5 is as follows: The first stage: injection temperature is 180-190℃, pressure is 60-70MPa, time is 5-8min, injection speed is 25-30mm / s, injection position is 50-60mm; The second stage: injection temperature is 200-220℃, pressure is 70-80MPa, time is 2-3min, injection speed is 30-40mm / s, injection position is 40-50mm.

[0027] By adopting the above technical solution, the injection temperature, pressure, time, speed and injection position are optimized to ensure that the injection components are fully melted, evenly distributed and filled in the mold, thereby obtaining a first wrapping layer with stable quality, good elasticity, moderate hardness and good toughness.

[0028] Preferably, the thickness ratio of the first wrapping layer to the second wrapping layer is 2:(0.8-1.2).

[0029] By adopting the above technical solution, the thickness ratio of the first wrapping layer to the second wrapping layer is optimized, the stability of the ear clip structure is further improved, which helps to resist external impact and deformation and protect the internal memory steel wire and FPC from damage.

[0030] Preferably, the silicone oil liquid is composed of silicone oil, surfactant and diluent in a weight ratio of 1:0.1:(2-3).

[0031] By adopting the above technical solution, a smooth film is formed on the surface core layer of the fake steel wire to prevent the fake steel wire from connecting with the first wrapping layer, while reducing the friction of the fake steel wire, making it easier to pull out. The silicone oil mainly plays a lubricating role. It can adhere to the surface of the fake steel wire to form a smooth protective film, which reduces the friction resistance of the fake steel wire when passing through the SR buckle, making the extraction process smoother. Surfactants can improve the surface tension of silicone oil, making it easier to spread on the surface of the fake steel wire, which is beneficial to the formation of a smooth film. The diluent in the silicone oil mainly plays the role of adjusting the viscosity and diluting the silicone oil. By adding a diluent, the viscosity of the silicone oil can be reduced, making it easier to be absorbed and carried by the fake steel wire.

[0032] In summary, this application has the following beneficial effects: 1. In the present application, a solid plastic wrapping layer is formed around the FPC through a specific preparation process, and the FPC is stably fixed in the ear clip structure, reducing the pulling and damage to the FPC caused by the deformation of the ear clip, and effectively preventing the FPC from falling off during use, thereby extending the service life of the FPC and the earphones. DETAILED DESCRIPTION Example

[0033] LSR silicone was purchased from Guangzhou Ruikexing Trading Co., Ltd. The brand is Momentive and the model is 40.

[0034] Polyethylene was purchased from Dongguan Julong Plastic Raw Materials Co., Ltd. The brand is SABIC and the model is 3H673.

[0035] TPU was purchased from Dongguan Zhenpin New Materials Co., Ltd. The brand is BASF of Germany and the grade is 1190A.

[0036] Ethylene-vinyl acetate copolymer was purchased from Guangzhou Jiushun New Materials Co., Ltd. The brand is French Arkema and the grade is 42-60.

[0037] SEBS was purchased from Guangzhou Jiushun New Materials Co., Ltd. The brand is American Kraton and the grade is G1726.

[0038] Example 1 A preparation process for an ear clip containing FPC for an ear clip type earphone, comprising the following preparation steps: S1. Prepare a memory steel wire, and bend the steel wire into a desired shape as required to obtain a curved memory steel wire; S2, placing the bending memory steel wire in a mold, and forming SR buckles with FPC holes at both ends of the bending memory steel ring through an SR molding process; The injection molding material used is composed of LSR silicone, coupling agent (vinyl triethoxysilane), filler (silicon dioxide) and polyethylene in a weight ratio of 10:0.5:5:2; The injection molding process in step S2 is as follows: The first stage: temperature is 110℃, injection pressure is 70MPa, injection speed is 20mm 3 / s, time is 15s; The second stage: temperature is 115℃, injection pressure is 60MPa, injection speed is 25mm 3 / s, time is 20s; The third stage: temperature is 110℃, injection pressure is 45MPa, injection speed is 15mm 3 / s, the time is 25s.

[0039] S3, soaking the fake steel wire in silicone oil, and then passing the soaked fake steel wire through one of the FPC holes, and then passing it out through another hole, so that the fake steel wire is parallel to the bending memory steel wire, and a frame is obtained; The silicone oil liquid is composed of silicone oil, surfactant (Tween) and diluent (ethyl acetate) in a weight ratio of 1:0.1:2; S4, placing the frame into a mold for injection molding, so that the upper part of the SR buckle, the bending memory steel wire and the fake steel wire are all wrapped by plastic to form a first wrapping layer, and a semi-finished product is obtained; The injection molding material used is composed of TPU, silane coupling agent (vinyl triethoxysilane), ethylene-vinyl acetate copolymer, filler (silicon dioxide) and polyethylene in a weight ratio of 10:1:5:4:2.

[0040] In step S4, the injection temperature is 200° C., the pressure is 50 MPa, the time is 4 min, the injection speed is 20 mm / s, and the injection position is 60 mm.

[0041] S5. Put the semi-finished product into the mold for injection molding, wrap a layer of plastic on the surface of the first layer of plastic to form a second wrapping layer, then remove the fake steel wire to form a channel, and then place the FPC in the channel to obtain the finished product.

[0042] The injection molding material used is composed of TPU, SEBS, silane coupling agent (vinyl triethoxysilane), ethylene-vinyl acetate copolymer, antioxidant (2,6-di-tert-butyl-p-cresol), filler (silicon dioxide) and polyethylene in a weight ratio of 15:8:1:5:0.1:4:2.

[0043] The injection molding process in step S5 is as follows: The first stage: injection temperature is 180℃, pressure is 60MPa, time is 5min, injection speed is 25mm / s, injection position is 50mm; The second stage: injection temperature is 200°C, pressure is 70MPa, time is 2min, injection speed is 30mm / s, and injection position is 40mm.

[0044] The thickness ratio of the first wrapping layer to the second wrapping layer is 2:0.8.

[0045] The difference between Example 2-3 and Example 1 is that the raw material types, amounts and experimental parameters for preparing the FPC ear clips for ear clip-type headphones are different. The specific differences are shown in Table 1: Table 1: Raw material types, amounts and experimental parameters for preparing FPC ear clips for ear clip-on headphones in Examples 1-3 Example 4 A preparation process for an ear clip-type earphone containing an FPC ear clip, the difference between this embodiment and embodiment 1 is that the injection molding process in step S2 is as follows: The first stage: temperature is 110℃, injection pressure is 70MPa, injection speed is 20mm 3 / s, time is 15-20s; Second stage: temperature 115°C, injection pressure 60-MPa, injection speed 25 mm 3 / s, time is 20-30s.

[0046] Example 5 A preparation process for an ear clip containing FPC for an ear clip type earphone. The difference between this embodiment and embodiment 1 is that the injection molding material used in step S4 is composed of TPU, silane coupling agent, ethylene-vinyl acetate copolymer, filler and polyethylene in a weight ratio of 5:1:5:4:2.

[0047] Example 6 A preparation process for an ear clip containing FPC for an ear clip type earphone. The difference between this embodiment and embodiment 1 is that the injection molding material used in step S5 is composed of TPU, SEBS, silane coupling agent, ethylene-vinyl acetate copolymer, antioxidant, filler and polyethylene in a weight ratio of 20:8:1:5:0.1:4:2.

[0048] Example 7 A preparation process for an ear clip-type earphone containing an FPC ear clip, the difference between this embodiment and embodiment 1 is that the injection molding process in step S5 is as follows: The injection temperature is 180°C, the pressure is 60 MPa, the time is 5 min, the injection speed is 25 mm / s, and the injection position is 50 mm.

[0049] Example 8 A preparation process for an ear clip-type earphone containing an FPC ear clip, the difference between this embodiment and embodiment 1 is that the injection molding process in step S5 is as follows: The injection temperature is 200°C, the pressure is 70 MPa, the time is 2 min, the injection speed is 30 mm / s, and the injection position is 40 mm.

[0050] Example 9 A preparation process for an ear clip containing FPC for an ear clip type earphone. The difference between this embodiment and embodiment 1 is that the injection molding material used in step S2 is composed of LSR silicone, coupling agent, filler and polyethylene in a weight ratio of 5:0.5:5:2.

[0051] Comparative Example Comparative Example 1 A preparation process of an FPC ear clip for an ear clip-type earphone. The difference between this comparative example and Example 1 is that the step S3 is immersed in pure water.

[0052] Comparative Example 2 A preparation process for an ear clip containing FPC for an ear clip type earphone. The difference between this comparative example and Example 1 is that the injection molding material used in step S4 is composed of TPU, SEBS, a silane coupling agent (vinyl triethoxysilane), ethylene-vinyl acetate copolymer, an antioxidant (2,6-di-tert-butyl-p-cresol), a filler (silicon dioxide) and polyethylene in a weight ratio of 15:8:1:5:0.1:4:2.

[0053] The injection molding process in step S4 is as follows: The first stage: injection temperature is 180℃, pressure is 60MPa, time is 5min, injection speed is 25mm / s, injection position is 50mm; The second stage: injection temperature is 200°C, pressure is 70MPa, time is 2min, injection speed is 30mm / s, and injection position is 40mm.

[0054] Comparative Example 3 A preparation process for an ear clip containing FPC for an ear clip type earphone. The difference between this comparative example and Example 1 is that the injection molding material used in step S5 is composed of TPU, a silane coupling agent (vinyl triethoxysilane), an ethylene-vinyl acetate copolymer, a filler (silicon dioxide) and polyethylene in a weight ratio of 10:1:5:4:2.

[0055] In step S4, the injection temperature is 200° C., the pressure is 50 MPa, the time is 4 min, the injection speed is 20 mm / s, and the injection position is 60 mm.

[0056] Comparative Example 4 A preparation process for an ear clip-type earphone containing an FPC ear clip. The difference between this comparative example and Example 1 is that an FPC circuit board is used in step S3 instead of a fake steel and is not pulled out in step S5.

[0057] Comparative Example 5 A preparation process of an FPC ear clip for an ear clip-type earphone. The difference between this comparative example and Example 1 is that TPU is used instead of LSR silicone in step S2.

[0058] Detection method / test method Among them, the fake steel wire in comparative example 1 could not be pulled out, so it did not participate in any experiments.

[0059] The FPC circuit was purchased from Shenzhen Hengxin Hengye Technology Co., Ltd., model number 075523703482. The FPC circuit was installed in the FPC ear clip prepared in Examples 1-9 and Comparative Examples 1-3 and 5 to obtain a sample, first tested whether it was powered on, and then subjected to a bending resistance test and an impact resistance test.

[0060] Power-on test: Use a multimeter to connect the two ends of the FPC. If you can hear a buzzing sound, it means the circuit is connected. If you can't hear a buzzing sound, it means the circuit is disconnected. If the circuit is disconnected, the remaining tests will not be performed.

[0061] Bending test: Place the sample in a wire swing tester, adjust the pressure to 2Kg, and swing it left and right during the test. After a certain number of times, take out the FPC and observe whether it is broken. Record the number of breaks, and record it every 500 times.

[0062] Impact resistance test: Place the sample on a horizontal surface, 3 meters above the ground, and let a weight of 1 kg fall freely onto the surface of the sample. Take out the FPC and observe whether it is broken. The same test is also carried out on Comparative Example 4, and then the first and second wrapping layers are torn apart to observe whether the FPC is broken or deformed.

[0063] Peeling test: Use a tensile testing machine to fix the SR buckle containing the FPC ear clip prepared in Examples 1-9 and Comparative Examples 1-3 and 5, then clamp the second wrapping layer, start the tensile testing machine until the SR buckle falls off, and record the force at this time.

[0064] Wearing comfort test: 50 people were selected to try on the FPC ear clips prepared in Examples 1-9 and Comparative Examples 1-3 and 5 in turn, and the number of people who felt comfortable was recorded.

[0065] The experimental data are shown in Table 2: Comparing Example 1 with Comparative Example 1, the fake steel wire cannot be extracted in Comparative Example 1, which will result in the failure of the process. In the present application, the silicone oil coating method is adopted to make the entire process smooth and fluent, and can be industrialized for production.

[0066] Comparing Example 1 with Comparative Example 4, in Comparative Example 4, the FPC is directly wrapped, which will result in no electricity after various steps. The preparation process in the present application can protect the FPC well during use and during production, thereby improving the yield rate.

[0067] Comparing Example 1 with Comparative Examples 2-3, the bending resistance times and peeling force of Comparative Examples 2-3 are less than those of Example 1, and Comparative Examples 1-2 are deformed and broken in the impact resistance test, respectively. The number of people who feel comfortable wearing the ear clips in Comparative Example 2 is less than that in Example 1, indicating that the preparation process in the present application can obtain ear clips that are comfortable to wear, have good impact resistance, are resistant to bending, and have a stable structure.

[0068] Comparing Example 1 with Comparative Example 5, the peeling force of Comparative Example 5 is smaller than that of Example 1, indicating that the SR buckle prepared by the formula of the present application has good connection stability with the memory steel wire and the first wrapping layer.

[0069] Comparing Example 1 with Example 4, the peeling force of Example 4 is smaller than that of Example 1, indicating that optimizing the injection molding parameters of step S2 is beneficial to improving the connection stability between the SR buckle, the memory steel wire, and the first wrapping layer.

[0070] Comparing Example 1 with Example 5, the bending resistance and peeling force of Example 5 are both lower than those of Example 1, indicating that optimizing the dosage of the formula of the first wrapping layer prepared in the present application is beneficial to improving the connection stability between the first wrapping layer and the memory steel wire and the SR buckle.

[0071] Comparing Example 1 with Example 6, the bending resistance and peeling force of Example 6 are both lower than those of Example 1, and the number of people who feel comfortable wearing the ear clip in Example 6 is lower than that in Example 1, indicating that the dosage of the formula of the second wrapping layer prepared by the present application is conducive to improving the bending resistance and comfort of the ear clip.

[0072] Comparing Example 1 with Examples 7-8, the bending resistance and peeling force of Examples 7-8 are both lower than those of Example 1, and the number of people who feel comfortable wearing the ear clips in Examples 7-8 is lower than that in Example 1, indicating that optimizing the injection molding parameters of step S5 is beneficial to the bending resistance and comfort of the ear clips.

[0073] Comparing Example 1 with Example 9, the peeling force of Example 9 is smaller than that of Example 1, indicating that optimizing the amount of injection molding raw materials in step S2 is beneficial to improving the connection stability between the SR buckle, the memory steel wire, and the first wrapping layer.

[0074] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A preparation process for an ear clip containing FPC for an ear clip type earphone, characterized in that: The method comprises the following preparation steps: S1. Prepare a memory steel wire, and bend the steel wire into a desired shape as required to obtain a curved memory steel wire; S2, placing the bending memory steel wire in a mold, and forming SR buckles with FPC holes at both ends of the bending memory steel ring through an SR molding process; S3, soaking the fake steel wire in silicone oil, and then passing the soaked fake steel wire through one of the FPC holes, and then passing it out through another hole, so that the fake steel wire is parallel to the bending memory steel wire, and a frame is obtained; S4, placing the frame into a mold for injection molding, so that the upper part of the SR buckle, the bending memory steel wire and the fake steel wire are all wrapped by plastic to form a first wrapping layer, and a semi-finished product is obtained; S5. Put the semi-finished product into the mold for injection molding, wrap a layer of plastic on the surface of the first layer of plastic to form a second wrapping layer, then remove the fake steel wire to form a channel, and then place the FPC in the channel to obtain the finished product.

2. The preparation process of the FPC ear clip for ear clip type headphones according to claim 1, characterized in that: The injection molding material used in step S2 is composed of LSR silicone, coupling agent, filler and polyethylene in a weight ratio of 10:0.5:5:(2-3).

3. The preparation process of the FPC ear clip for ear clip type headphones according to claim 1, characterized in that: The injection molding material used in step S4 is composed of TPU, silane coupling agent, ethylene-vinyl acetate copolymer, filler and polyethylene in a weight ratio of 10:1:5:4:(2-3).

4. The process for preparing the FPC ear clip for ear clip type headphones according to claim 1, characterized in that: The injection molding material used in step S5 is composed of TPU, SEBS, silane coupling agent, ethylene-vinyl acetate copolymer, antioxidant, filler and polyethylene in a weight ratio of 15:8:1:5:0.1:4:(2-3).

5. The process for preparing the FPC ear clip for ear clip type headphones according to claim 4, characterized in that: The hardness of the first wrapping layer is greater than the hardness of the second wrapping layer.

6. The process for preparing the FPC ear clip for ear clip type headphones according to claim 2, characterized in that: The injection molding process in step S2 is as follows: The first stage: temperature is 110-115℃, injection pressure is 70-75MPa, injection speed is 20-23mm 3 / s, time is 15-20s; The second stage: the temperature is 115-120℃, the injection pressure is 60-65 MPa, and the injection speed is 25-30mm 3 / s, time is 20-30s; The third stage: the temperature is 110-120℃, the injection pressure is 45-50 MPa, and the injection speed is 15-20 mm 3 / s, the time is 25s.

7. The process for preparing the FPC ear clip for ear clip type headphones according to claim 3, characterized in that: In step S4, the injection molding temperature is 200-220° C., the pressure is 50-60 MPa, the time is 4-6 min, the injection speed is 20-30 mm / s, and the injection position is 60-70 mm.

8. The process for preparing the FPC ear clip for ear clip type headphones according to claim 4, characterized in that: The injection molding process in step S5 is as follows: The first stage: injection temperature is 180-190℃, pressure is 60-70MPa, time is 5-8min, injection speed is 25-30mm / s, injection position is 50-60mm; The second stage: injection temperature is 200-220℃, pressure is 70-80MPa, time is 2-3min, injection speed is 30-40mm / s, injection position is 40-50mm.

9. The process for preparing the FPC ear clip for ear clip type headphones according to claim 8, characterized in that: The thickness ratio of the first wrapping layer to the second wrapping layer is 2:(0.8-1.2).

10. The process for preparing the FPC ear clip for ear clip type headphones according to claim 1, characterized in that: The silicone oil liquid is composed of silicone oil, surfactant and diluent in a weight ratio of 1:0.1:(2-3).

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