Magnetic assembly

Abstract

The utility model discloses a magnetic assembly. The magnetic assembly comprises a lead and a magnetic powder mixture. And the lead is embedded in the magnetic powder mixture. Wherein the magnetic powder mixture comprises first composite magnetic powder and second composite magnetic powder, and the first composite magnetic powder sequentially comprises magnetic powder, a thermosetting resin layer and a thermoplastic resin layer from inside to outside. The lead is embedded by the magnetic powder mixture to form a magnetic body. According to the magnetic assembly, the manufacturing steps of the magnetic core can be simplified, and the process cost can be reduced.

Description

Technical Field

[0001] This utility model relates to a magnetic component, and more particularly to a magnetic component that simplifies the magnetic manufacturing process and reduces the manufacturing cost. Background Technology

[0002] An inductor is a passive electronic component widely used in various electronic circuits. Therefore, as electronic products become smaller, the smaller the inductor, the better. An inductor typically consists of a magnetic core and leads; the magnetic core is made by pressing magnetic powder.

[0003] In the molding process, magnetic powder is typically cured by hot pressing, followed by a spray coating process to ensure a tight bond between the resin coating and the magnetic core, preventing it from peeling off easily when the core is subjected to impact. However, the existing magnetic core manufacturing methods involve complex steps, increasing processing costs.

[0004] Therefore, how to simplify the manufacturing process of magnetic cores and reduce the cost of manufacturing by improving the manufacturing method, thereby overcoming the above-mentioned defects, has become one of the important issues that this project aims to solve. Utility Model Content

[0005] The technical problem to be solved by this utility model is to provide a magnetic component that addresses the shortcomings of the prior art.

[0006] To address the aforementioned technical problems, one technical solution adopted by this utility model is to provide a magnetic component, which includes leads and a magnetic powder mixture. The leads are embedded in the magnetic powder mixture. The magnetic powder mixture includes a first composite magnetic powder and a second composite magnetic powder, and the first composite magnetic powder sequentially comprises magnetic powder, a thermosetting resin layer, and a thermoplastic resin layer from the inside out. The magnetic powder mixture embeds the leads to form a magnetic body.

[0007] Furthermore, the average particle size of the first composite magnetic powder ranges from 25 μm to 40 μm.

[0008] Furthermore, the average particle size of the second composite magnetic powder ranges from 25 μm to 40 μm.

[0009] Furthermore, the average particle size ratio of the first composite magnetic powder to the second composite magnetic powder ranges from 4.8 to 8.

[0010] Furthermore, the hardness of the first composite magnetic powder ranges from 200 to 600.

[0011] Furthermore, the hardness of the second composite magnetic powder ranges from 120 to 350.

[0012] Furthermore, the hardness difference between the first composite magnetic powder and the second composite magnetic powder is 150 to 480.

[0013] Furthermore, the weight ratio of the first composite magnetic powder to the second composite magnetic powder ranges from 0.25 to 1.85.

[0014] One of the beneficial effects of this utility model is that the magnetic component provided by this utility model can improve the density of the magnetic component through the technical solutions of "the magnetic component includes a lead wire and a magnetic powder mixture" and "the magnetic powder mixture includes a first composite magnetic powder and a second composite magnetic powder, and the first composite magnetic powder includes magnetic powder, a thermosetting resin layer and a thermoplastic resin layer in sequence from the inside to the outside".

[0015] To further understand the features and technical content of this utility model, please refer to the following detailed description and drawings of this utility model. However, the drawings provided are for reference and illustration only and are not intended to limit this utility model. Attached Figure Description

[0016] Figure 1 This is a perspective view of the first embodiment of the present utility model.

[0017] Figure 2 This is a perspective view of the second embodiment of the present utility model.

[0018] Figure 3 This is a perspective view of the third embodiment of the present utility model.

[0019] Figure 4 This is a perspective view of the fourth embodiment of the present utility model.

[0020] Figure 5 This is a three-dimensional schematic diagram of the fifth embodiment of the present utility model.

[0021] Figure 6 This is a perspective view of the sixth embodiment of the present utility model.

[0022] Figure reference numerals: 1A-1F: composite magnetic powder; 11: magnetic powder; 12: thermosetting resin layer; 13: thermoplastic resin layer; 14: coupling agent layer; 15: oxide powder layer; 16: dispersant layer; 17: metal oxide layer; 18: lubricant layer. Detailed Implementation

[0023] The following specific embodiments illustrate the implementation of the "magnetic component" disclosed in this utility model. Those skilled in the art can understand the advantages and effects of this utility model from the content disclosed in this specification. This utility model can be implemented or applied through other different specific embodiments, and various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the concept of this utility model. The following embodiments will further describe the relevant technical content of this utility model in detail, but the disclosed content is not intended to limit the protection scope of this utility model. Furthermore, the term "or" as used herein may include, depending on the actual situation, any combination of any one or more of the associated listed items.

[0024] This invention provides a magnetic component, which includes at least winding a lead wire, providing a magnetic powder mixture, and cold pressing. In embodiments of this invention, the method does not require high-temperature baking; the magnetic powder mixture can be solidified at room temperature. Furthermore, this invention can use round wire as the lead wire, and the lead wire can be wound into a spiral shape, with the number of turns adjustable according to different inductance requirements. Specifically, the lead wire can be wound using a needle, and then both ends of the lead wire can be spot-welded to electrodes for fixation.

[0025] Furthermore, the lead wire can be an insulated film lead wire. It is worth mentioning that the composite magnetic powder of this invention refers to magnetic powder particles containing a multi-layered structure. That is, the first composite magnetic powder and the second composite magnetic powder of this invention can each be selected from the composite magnetic powders of any of the embodiments described below.

[0026] In the embodiments of this utility model, see Figure 1 As shown, the composite magnetic powder 1A includes magnetic powder 11, a thermosetting resin layer 12, and a thermoplastic resin layer 13. The magnetic powder 11 can be iron powder, Fe-Cr-Si alloy, Fe-Si alloy, Fe-Al-Si alloy, Fe-Ni-Si alloy, Fe-Si-B alloy, Fe-Si-B-Cr alloy, Fe-Si-B-Cr alloy, Fe-Al-Cr alloy, Fe-Si-B-Nb-Cu alloy, Fe-Si-Cr-B-Nb-Cu alloy, and an amorphous alloy. In an optional embodiment of this invention, the magnetic powder can be iron powder, Fe-Cr-Si alloy, Fe-Si alloy, Fe-Al-Si alloy, and an amorphous alloy.

[0027] The thermosetting resin layer 12 is formed of silicone resin, such as methyl vinyl silicone resin and methyl phenyl vinyl silicone resin. However, the examples given above are merely one possible embodiment and are not intended to limit the present invention. Thermosetting silicone resin is viscous at room temperature, which facilitates the formation of the thermosetting resin layer of the present invention. In this embodiment, the content of the thermosetting resin layer is 0.5% to 1.7% of the total amount of composite magnetic powder, for example, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, and 1.6%. If the content of the thermosetting resin layer is less than 0.5%, the compressibility of the composite magnetic powder will be poor. If the content of the thermosetting resin layer is greater than 1.7%, the processing cost will increase.

[0028] In this embodiment, the thermoplastic resin layer 13 is formed of phenolic resin, which is obtained by the condensation reaction of phenolic compounds and aldehyde compounds. The content of the thermoplastic resin layer is 0.4% to 1.3% of the total amount of composite magnetic powder, for example, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, and 1.2%. If the content of the thermoplastic resin layer is less than 0.4%, the corrosion resistance of the composite magnetic powder is poor.

[0029] In the embodiments of this utility model, see Figure 2 As shown, the composite magnetic powder 1B further includes a coupling agent layer 14, which is directly formed on and coats the magnetic powder 11. The coupling agent layer 14 is formed of at least one coupling agent selected from the group consisting of silane coupling agents, titanate coupling agents, aluminate coupling agents, and zirconate coupling agents. However, the above examples are merely one possible embodiment and are not intended to limit the present invention.

[0030] In this embodiment, in order to obtain a suitable adhesion strength, the content of the coupling agent layer 14 is 0.0001% to 0.01% of the total amount of composite magnetic powder 1B, for example, 0.0002%, 0.0004%, 0.0006%, 0.0008%, 0.001%, 0.002%, 0.004%, 0.006%, and 0.008%.

[0031] In the embodiments of this utility model, see Figure 3 As shown, the composite magnetic powder 1C further includes an oxide powder layer 15 disposed between the coupling agent layer 14 and the thermosetting resin layer 12. The oxide powder layer 15 is formed of at least one oxide powder selected from the group consisting of silicon dioxide and titanium dioxide. However, the above-described examples are merely one possible embodiment and are not intended to limit the present invention. Furthermore, the oxide powder layer 15 may be formed of nano-oxide powder.

[0032] In this embodiment, the content of oxide powder layer 15 is 0.007% to 0.04% of the total amount of composite magnetic powder 1C, for example, 0.008%, 0.009%, 0.001%, 0.002%, or 0.03%.

[0033] In an embodiment of this invention, the oxide powder layer 15 may be formed by first forming a layer of nano-silica and then forming another layer of nano-titanium dioxide. Specifically, the content of nano-silica is 0.005% to 0.01% of the total amount of composite magnetic powder 1C, and the content of nano-titanium dioxide is 0.002% to 0.03% of the total amount of composite magnetic powder 1C.

[0034] In the embodiments of this utility model, see Figure 4 As shown, the composite magnetic powder 1D further includes a dispersant layer 16, which is formed on and covers the thermoplastic resin layer 13. Specifically, the dispersant layer may be formed of at least one dispersant selected from the group consisting of polyester amine salts, polyamides, polyethylimides, aliphatic polycarboxylate esters, sorbitan monooleate, and unsaturated fatty acid amine salts. However, the examples given above are merely one possible embodiment and are not intended to limit the present invention.

[0035] In this embodiment, the content of the dispersant layer 16 is 0.001% to 0.1% of the total amount of the composite magnetic powder 1D, for example, 0.002%, 0.004%, 0.006%, 0.008%, 0.01%, 0.02%, 0.04%, 0.06%, or 0.08%.

[0036] In the embodiments of this utility model, see Figure 5 As shown, the composite magnetic powder 1E further includes a metal oxide layer 17, which is formed on and covers the dispersant layer 16. Specifically, the metal oxide layer 17 can be formed of at least one metal oxide selected from the group consisting of aluminum oxide, zinc dioxide, nickel oxide, chromium oxide, manganese oxide, cobalt oxide, and magnesium oxide. However, the examples given above are merely one possible embodiment and are not intended to limit the present invention.

[0037] In this embodiment, the content of the metal oxide layer 17 is 0.005% to 0.01% of the total amount of composite magnetic powder 1E, for example, 0.006%, 0.007%, 0.008%, or 0.009%.

[0038] In the embodiments of this utility model, see Figure 6As shown, the composite magnetic powder also includes a lubricant layer 18, which is formed on and covers the metal oxide layer 17. Specifically, the lubricant layer 18 may be formed of at least one lubricant selected from the group consisting of zinc stearate, calcium stearate, lithium stearate, paraffin wax, synthetic polyethylene, stearyl alcohol, stearamide, oleamide, and erucamide. However, the examples given above are merely one possible embodiment and are not intended to limit the present invention.

[0039] In this embodiment, the content of the lubricant layer 18 is 0.001% to 0.005% of the total amount of composite magnetic powder 1F, for example, 0.002%, 0.003%, or 0.004%. A lubricant layer content of less than 0.001% will result in insufficient lubrication of the magnetic powder. If the lubricant layer content is greater than 0.005%, it will lead to a higher porosity between the magnetic powder particles, making it impossible to obtain magnetic powder with a high compression ratio.

[0040] Furthermore, the first and second composite magnetic powders of this invention have a difference in magnetic powder particle size, which is sufficient to allow the composite magnetic powder to be cold-pressed into a magnetic body. The magnetic powder mixture formed by mixing the first and second composite magnetic powders of this invention can be cold-pressed at a temperature from 40°C to 180°C to form a magnetic body. For example, the cold-pressing pressure can be from 5.2 Ton to 10 Ton.

[0041] Specifically, the average particle size of the first composite magnetic powder can range from 25 μm to 40 μm. The average particle size of the second composite magnetic powder can also range from 25 μm to 40 μm. The ratio of the average particle size of the first composite magnetic powder to the second composite magnetic powder can range from 4.8 to 8 to obtain a high-density magnetic material. In embodiments of this invention, the proportion of the first composite magnetic powder is ≤60%, so that the second composite magnetic powder can completely coat the first composite magnetic powder, that is, a smaller particle size powder coats a larger particle size powder, to further increase the density of the magnetic material during cold pressing. In other words, the weight ratio of the first composite magnetic powder to the second composite magnetic powder can range from 0.25 to 1.85.

[0042] On the other hand, the magnetic powder mixture of this invention comprises a first composite magnetic powder and a second composite magnetic powder. The hardness range of the first composite magnetic powder can be 200 to 600, and the hardness range of the second composite magnetic powder can be 120 to 350. In embodiments of this invention, the hardness of the second composite magnetic powder is less than that of the first composite magnetic powder. It is worth mentioning that the hardness difference between the first and second composite magnetic powders of this invention can be 150 to 480, so that during cold pressing, the magnetic powder mixture formed by mixing the first and second composite magnetic powders does not excessively compress the leads, causing lead deformation or displacement, thereby improving the problems of poor inductance and reduced inductance reliability.

[0043] In other words, when using the composite magnetic powder of this invention, if the hardness difference between the first and second composite magnetic powders falls outside the range of 150 to 480, a highly reliable inductor cannot be obtained through cold pressing. It should be noted that the hardness referred to herein is Vickers hardness.

[0044] Furthermore, the method of this invention does not require the use of a convex core and flat wire. As shown in Table 1 below, in the embodiments, round wire will be used instead of flat wire, and a convex core will not be used. The inductor will be manufactured according to the method of this invention (using the magnetic powder mixture of this invention). Comparative Examples 1 and 2 are inductors using conventional convex cores and flat wires.

[0045] Table 1

[0046]

[0047] Rdc: DC impedance

[0048] Isat: Saturation current; Li drop 30% refers to the current when the inductance value decreases by 30%.

[0049] Irms: Heating current; here defined as the current value corresponding to a 40°C increase in inductor temperature.

[0050] SRF (self-resonant frequency): self-resonant frequency

[0051] Generally, a smaller Rdc value is better, a larger Isat value is better, and a larger Irms value is better. According to the results in Table 1, the embodiments of this invention have the smallest Rdc value and equivalent or maximum Isat and Irms values. That is to say, although the magnetic component of this invention does not use a convex iron core and flat wire, it can achieve or surpass the characteristics of flat wire using traditional leadframe technology, thus saving on manufacturing costs.

[0052] Beneficial effects of the embodiments

[0053] One of the beneficial effects of this utility model is that the magnetic component provided by this utility model can simplify the manufacturing steps of the magnetic core and reduce the process cost by using the technical solutions of "the magnetic powder mixture includes a first composite magnetic powder and a second composite magnetic powder" and "the first composite magnetic powder includes magnetic powder, a thermosetting resin layer and a thermoplastic resin layer in sequence from the inside to the outside".

[0054] Furthermore, the magnetic components of this invention can be cold-pressed to form magnetic bodies. Magnetic bodies formed using this novel method can be directly subjected to processes such as folding, appearance inspection, packaging, and field-oriented control (FOC) after cold pressing, without requiring a further coating step, thus achieving corrosion resistance and preventing core peeling.

[0055] In detail, because the magnetic component of this invention uses composite magnetic powder with a multi-layered structure, it can pass salt spray tests without the need for spraying anti-corrosion materials during inductor manufacturing. Specifically, the inductor manufactured with the composite magnetic powder of this invention can pass a 24-hour rust prevention test in a salt spray environment with a temperature of 35℃±2℃, a salt content of 5%±1%, and a pH of 6.5~7.2. In other words, the composite magnetic powder of this invention can achieve carbon neutrality, making it more environmentally friendly than inductors that require the spraying of anti-corrosion materials.

[0056] The above-disclosed content is only a preferred and feasible embodiment of the present utility model, and is not intended to limit the scope of protection of the claims of the present utility model. Therefore, all equivalent technical changes made based on the content of the present utility model specification and drawings are included in the scope of protection of the claims of the present utility model.

Claims

1. A magnetic component, characterized in that, The magnetic component includes: Lead wire, wherein the lead wire is a round wire; A magnetic powder mixture, wherein the lead wire is embedded in the magnetic powder mixture; and The magnetic powder mixture is used to embed the lead wire to form a magnetic body.

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