Inductance device and preparation method thereof

Abstract

The invention discloses an inductance device and a preparation method thereof.The method comprises the steps that aluminum oxide and epoxy resin are mixed according to a preset proportion, and an injection molding raw material is obtained; the injection molding raw materials are added into a charging barrel of injection molding equipment, and the target magnetic core is placed into a cavity of an injection mold; the injection mold is moved to injection molding equipment for mold locking; injection molding equipment is controlled to pour injection molding raw materials into an injection molding cavity, and the injection molding raw materials enter a cavity of the injection mold through a nozzle; when a cavity of the injection mold is filled with the injection molding raw material, the injection molding raw material is subjected to pressure maintaining for first preset time; cooling for a second preset time through a cooling system arranged in the injection mold; and demolding to obtain the inductive device with the plastic shell formed on the surface of the target magnetic core. The problems that the consistency and the yield of the inductor device cannot be well guaranteed in an existing magnetic core shell mounting mode, the production cost of the inductor device is high due to manual participation of magnetic core shell mounting, and the market competitiveness is insufficient are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of inductor manufacturing, and particularly relates to an inductor device and a preparation method thereof. Background Art

[0002] As an important part of electronic components, inductors are widely used in many fields such as home appliances, communications, automotive electronics, and power. The stability of its performance and the delicacy of its appearance are directly related to the quality and market competitiveness of the overall product. The primary function of the inductor plastic housing is to isolate the inside of the inductor from the external environment, prevent harmful substances such as moisture and dust from invading, and thus avoid the decline or failure of the inductor performance caused by environmental factors. Secondly, as an important component for protecting the internal components of the inductor and providing structural support, the inductor housing provides a strong external support for the inductor, effectively resisting external mechanical shocks and vibrations. As an important component for protecting the internal components of the inductor and providing structural support, its preparation process is particularly critical.

[0003] The common current method for installing the magnetic core into the housing is to first obtain a plastic housing through 3D printing or injection molding, then fix the magnetic core inside the magnetic core housing by manual dispensing, and finally install the housing. Since most of the steps of this housing installation method are completed manually, the consistency and yield of the inductor device cannot be well guaranteed. Moreover, due to the large amount of manual participation, the labor cost is greatly increased, making the production cost of the product very high, and thus it does not have strong competitiveness in the market. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide an inductor device and a preparation method thereof, aiming to solve the problems that the consistency and yield of the inductor device cannot be well guaranteed by the existing magnetic core housing installation method, and the high production cost of the inductor device caused by manual participation in the magnetic core housing installation, resulting in insufficient market competitiveness.

[0005] The first aspect of the present invention lies in providing a preparation method of an inductor device, and the method includes:

[0006] Obtain alumina and epoxy resin respectively, and mix the alumina and epoxy resin according to a preset ratio to obtain an injection molding raw material;

[0007] Add the injection molding raw material into the barrel of the injection molding equipment, and place the target magnetic core into the cavity of the injection molding mold;

[0008] Move the injection molding mold to the injection molding equipment, drive the injection molding mold to align and close through the hydraulic system, and perform mold clamping;

[0009] Control the injection molding equipment to pour the injection molding raw material into the injection cavity, and through heating and plasticization, make the injection molding raw material enter the cavity of the injection mold through the nozzle;

[0010] When the injection molding raw material fills the cavity of the injection mold, carry out pressure holding on the injection molding raw material for a first preset time;

[0011] After carrying out pressure holding on the injection molding raw material for the first preset time, cool for a second preset time through the cooling system built in the injection mold, so that the injection molding raw material cools and solidifies in the cavity;

[0012] Drive the injection mold to demold through the hydraulic system to obtain an inductor device with a plastic shell formed on the surface of the target magnetic core.

[0013] According to one aspect of the above technical solution, the steps of respectively obtaining alumina and epoxy resin and mixing the alumina and epoxy resin in a preset ratio to obtain the injection molding raw material include:

[0014] Respectively obtain alumina and epoxy resin, and prepare materials according to the ratio of (1-3):1;

[0015] Add the prepared alumina and epoxy resin to a preset mixing device in sequence, and control the mixing device to move to mix the alumina and epoxy resin.

[0016] According to one aspect of the above technical solution, the steps of controlling the injection molding equipment to pour the injection molding raw material into the injection cavity, and through heating and plasticization, make the injection molding raw material enter the cavity of the injection mold through the nozzle include:

[0017] Control the injection molding equipment to pour the injection molding raw material into the injection cavity, and heat the injection molding raw material in the injection cavity to plasticize the injection molding raw material;

[0018] Control the injection molding raw material in the injection cavity to enter the cavity of the injection mold through the nozzle.

[0019] According to one aspect of the above technical solution, in the step of controlling the injection molding equipment to pour the injection molding raw material into the injection cavity and heating the injection molding raw material in the injection cavity to plasticize the injection molding raw material, the heating temperature for heating the injection molding raw material is 200°C - 260°C, and the heating time is 100s - 300s.

[0020] According to one aspect of the above technical solution, in the step of carrying out pressure holding on the injection molding raw material for a first preset time when the injection molding raw material fills the cavity of the injection mold, the first preset time is 30s - 200s.

[0021] According to one aspect of the above technical solution, after holding the injection molding raw material for the first preset time, it is cooled for the second preset time through the cooling system built in the injection mold, so that in the step of cooling and solidifying the injection molding raw material in the cavity, the second preset time is 20s - 60s, and the cooling rate is 5℃ / s - 8℃ / s.

[0022] According to one aspect of the above technical solution, the step of driving the injection mold to demold through the hydraulic system to obtain an inductor device with a plastic shell formed on the surface of the target magnetic core includes:

[0023] Start the hydraulic system, and drive the moving mold and the fixed mold of the injection mold to gradually separate through the hydraulic system to release the formed inductor device;

[0024] After the mold is separated, take out the inductor device from the injection mold through the robotic arm to obtain an inductor device with a plastic shell formed on the surface of the target magnetic core.

[0025] The second aspect of the present invention is to provide an inductor device, which is prepared by the preparation method described in the above technical solution.

[0026] According to one aspect of the above technical solution, the inductor device includes a magnetic core and a plastic shell.

[0027] According to one aspect of the above technical solution, the magnetic core is an annular magnetic core, and the thickness of the plastic shell is 0.5mm - 1.5mm.

[0028] Compared with the prior art, the beneficial effects of using the inductor device and its preparation method shown in the present invention are as follows:

[0029] (1) The outer shell material is subjected to a composite design, and the method of combining inorganic materials such as alumina and organic substances is adopted, which can not only ensure the fluidity and strength required for the injection molding outer shell material, but also match the expansion coefficient of the metal material; the close expansion coefficient makes the phenomenon of performance fluctuation caused by internal stress in the previous metal magnetic ring disappear.

[0030] (2) The direct injection molding method is adopted, which can not only achieve efficient and consistent production, but also reduce the size of the magnetic ring product to achieve the purpose of miniaturization. At the same time, due to the smaller size, the usage amount of the subsequent winding copper wire is reduced, and the cost is better reduced.

[0031] (3) Different from the traditional casing method, processes such as dispensing and casing are omitted, and the degree of automation is significantly improved. Therefore, not only the raw material cost and labor cost are saved, but also the yield rate of the product can be improved, so that the product cost is significantly reduced and the market competitiveness is stronger. Description of the Drawings

[0032] The above and / or additional aspects and advantages of the present invention will become obvious and easy to understand from the description of the embodiments in conjunction with the following drawings, where:

[0033] Figure 1 It is a schematic flow chart of a preparation method of an inductor device in an embodiment of the present invention. Detailed implementation manners

[0034] To make the objectives, features, and advantages of the present invention more obvious and understandable, the following provides a detailed description of the specific implementation manners of the present invention in conjunction with the drawings. Several embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present invention more thorough and comprehensive.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0036] Embodiment 1

[0037] Please refer to Figure 1 , the first embodiment (Embodiment Case 1) of the present invention provides a preparation method of an inductor device, and the method includes steps S10 - S70:

[0038] Step S10, respectively obtain alumina and epoxy resin, and mix the alumina and epoxy resin according to a preset ratio to obtain an injection molding raw material.

[0039] Among them, the step of respectively obtaining alumina and epoxy resin and mixing the alumina and epoxy resin according to a preset ratio to obtain an injection molding raw material includes:

[0040] Respectively obtain alumina and epoxy resin, and prepare materials according to a ratio of (1 - 3):1;

[0041] Sequentially add the prepared alumina and the epoxy resin into a preset mixing device, and control the mixing device to move to mix the alumina and the epoxy resin.

[0042] Step S20, add the injection molding raw material into the barrel of an injection molding device, and place a target magnetic core into the cavity of an injection molding mold.

[0043] Step S30: Move the injection mold onto the injection device, drive the injection mold through the hydraulic system for alignment and closing, and perform mold clamping.

[0044] Step S40: Control the injection device to pour the injection raw material into the injection cavity. After heating and plasticizing, make the injection raw material enter the cavity of the injection mold through the nozzle.

[0045] Among them, the step of controlling the injection device to pour the injection raw material into the injection cavity, heating and plasticizing it, and making the injection raw material enter the cavity of the injection mold through the nozzle includes:

[0046] Control the injection device to pour the injection raw material into the injection cavity, heat the injection raw material in the injection cavity to plasticize it.

[0047] Control the injection raw material in the injection cavity to enter the cavity of the injection mold through the nozzle.

[0048] Specifically, in the step of controlling the injection device to pour the injection raw material into the injection cavity, heating the injection raw material in the injection cavity to plasticize it, the heating temperature for heating the injection raw material is 200°C - 260°C, and the heating time is 100s - 300s.

[0049] Step S50: When the injection raw material fills the cavity of the injection mold, perform pressure holding on the injection raw material for a first preset time.

[0050] Among them, in the step of performing pressure holding on the injection raw material for a first preset time when the injection raw material fills the cavity of the injection mold, the first preset time is 30s - 200s.

[0051] Step S60: After performing pressure holding on the injection raw material for a first preset time, cool it through the cooling system built in the injection mold for a second preset time to cool and solidify the injection raw material in the cavity.

[0052] Among them, in the step of cooling through the cooling system built in the injection mold for a second preset time to cool and solidify the injection raw material in the cavity after performing pressure holding on the injection raw material for a first preset time, the second preset time is 20s - 60s, and the cooling rate is 5°C / s - 8°C / s.

[0053] Step S70: Drive the injection mold through the hydraulic system for demolding to obtain an inductor device with a plastic shell formed on the surface of the target magnetic core.

[0054] Among them, the step of driving the injection mold to demold through a hydraulic system to obtain an inductor device with a plastic shell formed on the surface of the target magnetic core includes:

[0055] Start the hydraulic system, and drive the moving mold and the fixed mold of the injection mold to gradually separate through the hydraulic system to release the formed inductor device;

[0056] After the mold is separated, use a robotic arm to take out the inductor device from the injection mold to obtain an inductor device with a plastic shell formed on the surface of the target magnetic core.

[0057] It is easy to understand that the method shown in this embodiment includes: directly injection molding using an injection molding machine, placing the magnetic core into the injection mold, and controlling the unilateral thickness of the inductor shell by designing the mold size, so as to ensure the appearance size of the product; using a combination of alumina and organic epoxy resin to conduct a composite design on the shell material, which can not only ensure the fluidity and strength required for the injection molded shell material, but also match the expansion coefficient of the metal material because the expansion coefficient of alumina is close to that of the metal. Since the expansion coefficients are very close, the influence of the internal stress generated by the thermal expansion of the inductor on its performance is greatly reduced.

[0058] Specifically, different from the traditional method of installing the shell on the magnetic core, directly injection molding the magnetic core shell can not only achieve efficient production, but also the inductor device formed by direct injection molding has better consistency. Moreover, for the product installed with the shell in the traditional way, there will be a gap between the magnetic ring and the plastic shell, and the gap is 1-2 mm. However, for the product formed by direct injection molding, the magnetic ring and the magnetic core shell are tightly fitted together without any gap. Therefore, the direct injection molding method can not only produce efficiently and with good consistency, but also reduce the size of the magnetic ring product to achieve the goal of product miniaturization. At the same time, due to the smaller size, the usage amount of the subsequent winding copper wire is reduced, and the cost is better reduced.

[0059] Secondly, compared with the traditional method of installing the shell, processes such as dispensing and shell installation are omitted, and the degree of automation is significantly improved. Therefore, not only the raw material cost and labor cost are saved, but also the yield rate of the product can be improved, resulting in a significant decrease in the product cost and greater market competitiveness.

[0060] In addition, the influence of the coefficient of thermal expansion on the inductor device is as follows: (1) Variation of the inductance value. When the inductor is heated or cooled, due to the different coefficients of thermal expansion of the materials, its structure or dimensions will change. When the temperature rises, the inductor usually expands, resulting in a decrease in the number of turns of the coil, and thus a decrease in the inductance value. Conversely, when the temperature drops, the inductor contracts, the number of turns of the coil increases, and the inductance value increases. This characteristic of the inductance value changing with temperature may have a significant impact in some applications with high requirements for inductance value accuracy (such as precision circuits in the fields of communication, computers, etc.). (2) Variation of electrical performance parameters. In addition to the inductance value, thermal expansion may also affect other electrical performance parameters of the inductor, such as the quality factor (Q value), impedance, etc. The change of these parameters will directly affect the working effect of the inductor device in the circuit, and thus affect the performance and stability of the entire application behind the inductor. (3) Damage caused by internal stress. Inductors usually use plastic casings. Due to the different coefficients of thermal expansion between the plastic casing and the internal magnetic core. When the temperature changes, the thermal expansion difference between different materials will lead to the accumulation of internal stress. If the stress is too large, it will cause cracks, deformation or other damages to the inductor, thus affecting its performance and lifespan.

[0061] As a specific example, the method shown in this embodiment includes:

[0062] (1) Add alumina and organic epoxy resin into a mixing device in a ratio of 2:1 for mixing. After mixing according to the designed process, the raw material for directly injection-molding the casing is obtained;

[0063] (2) Add the mixed casing raw material into the barrel of the injection molding machine;

[0064] (3) Place the 270 magnetic core into the cavity of the injection mold. The injection mold is a one-out-of-eighty mold;

[0065] (4) Move the injection mold to the injection molding machine and use the hydraulic system to provide power to achieve the correct alignment and closing of the injection mold;

[0066] (5) Execute the mold clamping program to ensure that the injection mold is completely closed and locked, preparing for the subsequent injection process;

[0067] (6) The injection molding machine feeds the casing raw material into the injection cavity. After heating and plasticizing, control the injection speed, pressure and time of the injection molding machine, and inject the molten casing raw material into the cavity of the injection mold through the nozzle;

[0068] (7) After the casing raw material fills the cavity of the injection mold, the injection molding machine applies a certain pressure between the barrel and the injection mold to ensure the appearance and performance quality of the inductor;

[0069] (8) After the pressure holding is completed, the injection molding machine continues to apply pressure, and at the same time opens the cooling system in the injection mold to cool and solidify the inductor casing;

[0070] (9) After the cooling and solidification are completed, the injection mold is opened through the hydraulic system, and the inductor wrapped with the outer shell is pushed out from the injection mold, so as to obtain an inductor device with a directly injection-molded outer shell.

[0071] In addition, the present invention also provides a comparative example (Example 2), which adopts the traditional manual shell loading method, and its preparation method includes the following steps:

[0072] (1) Design the outer shell size, and obtain the outer shell through 3D printing or injection molding;

[0073] (2) Put the 270 magnetic core into half of the outer shell, and use a dispensing machine to fix the 270 magnetic core inside half of the outer shell:

[0074] (3) Install the other half of the outer shell on the half of the outer shell where the magnetic core has been fixed:

[0075] (4) Place the inductor with the installed outer shell on a horizontal table and let it stand for a period of time to fully cure the glue:

[0076] (5) Put the inductor after standing into a drying oven for drying treatment. The temperature of the drying oven is controlled at 40°C - 50°C, and the drying time is 5 - 10 minutes.

[0077] (6) After the drying treatment is completed, take out the inductor to obtain the inductor with the installed outer shell.

[0078] Among them, the inductor prepared by the method shown in this embodiment is tested for the change of inductance value at high and low temperatures, and the results are shown in Table 1;

[0079] The production efficiency and product qualification rate of the inductor prepared by the method shown in this embodiment are counted, and the results are shown in Table 2;

[0080] The appearance dimensions of the inductor prepared by the method shown in this embodiment are measured, and the results are shown in Table 3.

[0081] Table 1

[0082]

[0083] From the test results shown in Table 1 above, it can be concluded that by using the method of composite design of the outer shell raw material with alumina and organic epoxy resin as shown in this embodiment, since the expansion coefficients of alumina and metal are close to each other, when the inductor is in high-temperature and low-temperature environments, the change of its inductance value remains within ±10%. For the inductor device made by the traditional shell loading method, in such extreme environments, the change of its inductance value fluctuates too much. Therefore, the inductor produced by injection molding using the method of composite design of the outer shell raw material shown in this embodiment can well ensure its good performance in extreme environments.

[0084] Table 2

[0085] Number Time Number of People Quantity Product Pass Rate Implementation Case - 1h 1000 PCS 99％ Implementation Case Two 1h 5 500 PCS 90％

[0086] From the data results obtained through Table 2, it can be concluded that the direct injection molding method for the outer shell used in this embodiment is different from the traditional housing method, eliminating processes such as dispensing and housing installation, significantly improving the degree of automation. Therefore, not only the raw material cost and labor cost are saved, but also the yield rate of the product can be improved, thus significantly reducing the product cost and making it more competitive in the market.

[0087] Table 3

[0088] Number OD ID HT Bare Magnetic Core 26.92 ± 0.1 mm 14.73 ± 0.1 mm 11.18 ± 0.1 mm Implementation Case One 28.92 ± 0.1 mm 12.73 ± 0.1 mm 13.18 ± 0.1 mm Implementation Case Two 30.92 ± 0.5 mm 10.73 ± 0.5 mm 15.18 ± 0.5 mm

[0089] From the data obtained through Table 3, it can be concluded that through the preparation method of the high-efficiency direct injection molded inductor housing shown in this embodiment, the size of the inductor can be accurately controlled. It can not only achieve high-efficiency and good consistency in production, but also reduce the size of the magnetic ring product to achieve miniaturization. At the same time, due to the smaller size, the usage amount of the subsequent winding copper wire is reduced, better reducing the cost.

[0090] An inductor device is prepared by using the above preparation method, which includes a ring-shaped magnetic core and a plastic housing wrapped on the surface of the magnetic core. The thickness of the plastic housing is 0.5 mm - 1.5 mm, and the plastic housing is directly formed by injection molding, with no gap between the plastic housing and the injection molded housing.

[0091] In summary, compared with the prior art, the beneficial effects of using the preparation method of the inductor device shown in this embodiment are as follows:

[0092] (1) Conduct a composite design on the outer shell material, and use a combination of inorganic materials such as alumina and organic substances. This can not only ensure the fluidity and strength required for the injection molded outer shell material, but also match the expansion coefficient of the metal material; the close expansion coefficient eliminates the phenomenon of performance fluctuations caused by internal stress in the previous metal magnetic ring.

[0093] (2) Adopt the direct injection molding method, which can not only achieve high-efficiency and good consistency in production, but also reduce the size of the magnetic ring product to achieve miniaturization. At the same time, due to the smaller size, the usage amount of the subsequent winding copper wire is reduced, better reducing the cost.

[0094] (3) Different from the traditional housing method, it eliminates processes such as dispensing and housing installation, significantly improving the degree of automation. Therefore, not only the raw material cost and labor cost are saved, but also the yield rate of the product can be improved, thus significantly reducing the product cost and making it more competitive in the market.

[0095] In the description of this specification, the descriptions referring to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0096] The above-described embodiments merely represent several implementation manners of the present invention. The descriptions thereof are relatively specific and detailed, but should not be construed as a limitation on the scope of the patent of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the appended claims.

Claims

1. A method for manufacturing an inductor device, characterized in that, The method includes: Obtaining alumina and epoxy resin respectively, mixing the alumina and epoxy resin in a preset ratio to obtain an injection molding raw material; Adding the injection molding raw material into the barrel of an injection molding device, and placing a target magnetic core into the cavity of an injection mold; Moving the injection mold to the injection molding device, driving the injection mold to align and close through a hydraulic system, and performing mold clamping; Controlling the injection molding device to pour the injection molding raw material into the injection cavity, and through heating and plasticizing, enabling the injection molding raw material to enter the cavity of the injection mold through a nozzle; When the injection molding raw material fills the cavity of the injection mold, performing pressure holding on the injection molding raw material for a first preset time; After performing pressure holding on the injection molding raw material for the first preset time, cooling for a second preset time through a cooling system built in the injection mold, so that the injection molding raw material cools and solidifies in the cavity; Driving the injection mold to demold through a hydraulic system to obtain an inductor device with a plastic shell formed on the surface of a target magnetic core.

2. The manufacturing method of the inductor device according to claim 1, characterized in that, The step of obtaining alumina and epoxy resin respectively, mixing the alumina and epoxy resin in a preset ratio to obtain an injection molding raw material includes: Obtaining alumina and epoxy resin respectively, and preparing materials in a ratio of (1 - 3):1; Sequentially adding the prepared alumina and epoxy resin into a preset mixing device, and controlling the mixing device to move to mix the alumina and epoxy resin.

3. The manufacturing method of the inductor device according to claim 1, characterized in that The step of controlling the injection molding device to pour the injection molding raw material into the injection cavity, and through heating and plasticizing, enabling the injection molding raw material to enter the cavity of the injection mold through a nozzle includes: Controlling the injection molding device to pour the injection molding raw material into the injection cavity, heating the injection molding raw material in the injection cavity to plasticize the injection molding raw material; Controlling the injection molding raw material in the injection cavity to enter the cavity of the injection mold through a nozzle.

4. The manufacturing method of the inductor device according to claim 3, wherein, In the step of controlling the injection molding device to pour the injection molding raw material into the injection cavity, heating the injection molding raw material in the injection cavity to plasticize the injection molding raw material, the heating temperature for heating the injection molding raw material is 200°C - 260°C, and the heating time is 100s - 300s.

5. The manufacturing method of the inductor device according to claim 1, characterized in that, In the step of performing pressure holding on the injection molding raw material for a first preset time when the injection molding raw material fills the cavity of the injection mold, the first preset time is 30s - 200s.

6. The manufacturing method of the inductor device according to claim 1, characterized in that, In the step of cooling for a second preset time through a cooling system built in the injection mold after performing pressure holding on the injection molding raw material for the first preset time, so that the injection molding raw material cools and solidifies in the cavity, the second preset time is 20s - 60s, and the cooling rate is 5°C / s - 8°C / s.

7. The manufacturing method of the inductor device according to any one of claims 1-6, characterized in that, The step of driving the injection mold to demold through a hydraulic system to obtain an inductor device with a plastic shell formed on the surface of a target magnetic core includes: Starting the hydraulic system, driving the moving mold and the fixed mold of the injection mold to gradually separate through the hydraulic system to release the formed inductor device; After the mold is separated, taking out the inductor device from the injection mold through a robotic arm to obtain an inductor device with a plastic shell formed on the surface of a target magnetic core.

8. An inductor device, characterized in that, The inductor device is prepared by the preparation method described in any one of claims 1-7.

9. The inductor device according to claim 8, characterized in that, The inductor device includes a magnetic core and a plastic housing.

10. The inductor device according to claim 9, characterized in that, The magnetic core is a toroidal magnetic core, and the thickness of the plastic housing is 0.5 mm - 1.5 mm.

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