Magnetic core, inductor, and EMI filter comprising the same

Abstract

To provide a magnetic core part excellent in magnetic properties and strength, and an inductor and an EMI filter that include the magnetic core part.SOLUTION: In an inductor, a magnetic core 800A comprises: a first magnetic body 810 having a toroidal shape, and including a ferrite; and a second magnetic body 820 disposed on an outer circumferential surface or an inner circumferential surface of the first magnetic body. The second magnetic body 820 includes: a second outer magnetic body 822 disposed on the outer circumferential surface S2 of the first magnetic body 810; and a second inner magnetic body 824 disposed on the inner circumferential surface S4 of the first magnetic body 810. The second outer magnetic body 822 and the second inner magnetic body 824 each have a thickness smaller than the thickness of the first magnetic body 810, and are obtained by forming a resin material on a metal ribbon wound in multiple layers.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a magnetic core, an inductor, and an EMI filter including the same. [Background technology]

[0002] An inductor is an electronic component that is applied to a printed circuit board and has electromagnetic properties. This can be applied to a resonant circuit, a filter circuit, a power circuit, etc.

[0003] On the other hand, EMI (Electro Magnetic In) applied inside the power board An interference filter passes the signals necessary for the circuit to operate and removes noise. This role is to

[0004] Figure 1 shows a typical power board with an EMI filter connected to a power supply and a load. FIG.

[0005] The types of noise transmitted from the power board of the EMI filter shown in Figure 1 are broadly The radiated noise of 30MHz to 1GHz emitted from the power board and the noise transmitted through the power line This can be divided into conducted noise in the range of 150 kHz to 30 MHz and conducted noise in the range of 150 kHz to 30 MHz.

[0006] The transmission method of conductive noise is the same as that of differential mode. Common mode noise is a small Even if the amount of radiation is small, it returns in a large loop and may not reach electronic devices located far away. Such common mode noise can also affect the impedance imbalance of the wiring system. This can also occur due to noise, and is more pronounced in high frequency environments.

[0007] In order to eliminate common mode noise, the inductor applied to the EMI filter shown in Figure 1 The toroidal rotor is generally made of Mn-Zn ferrite material. The magnetic core is oroidal. Mn-Zn ferrite is used for 100kHz to 1 Its high permeability at MHz allows it to effectively filter out common mode noise.

[0008] FIG. 2 is a perspective view showing a typical inductor 100. As shown in FIG.

[0009] Referring to FIG. 2, the inductor 100 includes a magnetic core 110 and a It may include a wound coil 120 .

[0010] The magnetic core 110 may be toroidal in shape, and the coil 120 may be a magnetic A first coil 122 is wound on the magnetic core 110, and a second coil 123 is wound opposite the first coil 122. The first coil 122 and the second coil 124 may include a second coil 124. The toroidal magnetic core 110 may be wound on an upper surface S1, a side surface S2, and a lower surface S3. do.

[0011] The magnetic core 110 may further include a bobbin (not shown) for insulating the coil 120. The coil 120 may be made of a conductive wire having a surface coated with an insulating material.

[0012] FIG. 3 is an exploded perspective view of the magnetic core shown in FIG. 2 further including a bobbin, and FIG. 4 is a perspective view showing a process for manufacturing the magnetic core shown in FIG. 3.

[0013] 3, the magnetic core 110 may be housed in a bobbin 130. The bobbin 130 may include: An upper bobbin 132 and a lower bobbin 134 may be included.

[0014] Next, referring to FIG. 4(a), the upper bobbin 132, the magnetic core 110 and the With the lower bobbin 132 provided, the magnetic core 110 is disposed on the bottom surface of the lower bobbin 132. Then, as shown in FIG. 4(b), the upper bobbin is added to the result shown in FIG. 4(a). At this time, each component may be bonded to each other with an adhesive material.

[0015] In order to improve the performance of the inductor described above, the magnetic core 110 may be made of a different material. As an example, the Mn-Zn ferrite (F The surface of a toroidal magnetic core containing errite material is In some cases, Fe-Si-based metal ribbons may be arranged in the structure. However, metal ribbons have high magnetic properties. Heat treatment at high temperatures (e.g., 500°C to 600°C) to obtain the desired properties (i.e., high magnetic permeability) However, metal ribbons that have been heat-treated at high temperatures tend to retain their magnetic properties. Although the strength is improved, the strength is also weakened, so it is easily broken by even a small impact (brittle). ) which makes transportation and handling during the manufacturing process extremely difficult, resulting in reduced workability. This leads to a problem of a decrease in the yield of the finished product. Summary of the Invention [Problem to be solved by the invention]

[0016] The technical problem that the present invention aims to achieve is to provide a magnetic core part having excellent magnetic properties and strength, and The present invention provides an inductor and an EMI filter including: [Means for solving the problem]

[0017] The inductor according to one embodiment has a toroidal shape and includes a first magnetic material including ferrite. and a second magnetic body disposed on an outer circumferential surface or an inner circumferential surface of the first magnetic body, The first magnetic body includes a plurality of layers of metal ribbons and a resin material wound around the circumference of the first magnetic body. The resin material is a first resin material arranged to cover the outer surface of the multiple layers of metal ribbons, and a multiple layer and a second resin material disposed in at least a portion of the interlayer space.

[0018] For example, the first magnetic body includes a Mn-Zn ferrite and the second magnetic body includes a Fe-Si metal. The second resin material includes a ribbon, and the second resin material extends from the lower surface to the upper surface of the second magnetic body relative to the entire height of the second magnetic body. It can be placed in the range of 0% to 5% and in the range of 95% to 100%.

[0019] For example, the thickness of the first magnetic body in the diametrical direction is greater than the thickness of the second magnetic body in the diametrical direction, and The magnetic body may have a diametrical thickness greater than the diametrical thickness of the first resin material.

[0020] For example, the thickness of the first resin material may be from 20 μm to 30 μm.

[0021] For example, the height of the first resin material layer may be greater than the height of the second magnetic body.

[0022] For example, the second resin material may be disposed in an amount of 15% to 30% relative to the interlayer spaces between the multiple layers.

[0023] For example, the second resin material may be disposed in an amount of 20% to 25% relative to the interlayer spaces between the multiple layers.

[0024] The EMI filter according to the embodiment includes an inductor and a capacitor. The magnet has a toroidal shape and includes a first magnetic body containing ferrite, and the first magnetic body has an outer circumferential surface or an inner circumferential surface thereof. a second magnetic body arranged on the circumferential surface of the first magnetic body, the second magnetic body being arranged along the circumferential direction of the first magnetic body; The metal ribbon may include multiple layers of a wound metal ribbon and a resin material, where the resin material is A first resin material is disposed so as to cover the outer surfaces of the multiple layers of metal ribbons, and a space between the multiple layers is disposed. and a second resin material disposed at least partially therebetween.

[0025] For example, the first magnetic body includes a Mn-Zn ferrite and the second magnetic body includes a Fe-Si metal. The second resin material includes a ribbon, and the second resin material extends from the lower surface to the upper surface of the second magnetic body relative to the entire height of the second magnetic body. It can be placed in the range of 0% to 5% and in the range of 95% to 100%.

[0026] For example, a portion of the second resin material may be disposed in an amount of 15% to 30% relative to the interlayer space of the plurality of layers. do. Effect of the Invention

[0027] The inductor and the EMI filter including the inductor according to the embodiment are formed by winding multiple layers of The metal ribbon-shaped magnetic core is coated with a resin material, improving strength while providing excellent It has excellent magnetic properties. [Brief description of the drawings]

[0028] [Figure 1] This is a block diagram of a general power board to which an EMI filter is applied, connected to a power supply and a load. [Diagram 2] FIG. 1 is a perspective view showing a general inductor. [Diagram 3] 3 is an exploded perspective view showing a case where the magnetic core shown in FIG. 2 further includes a bobbin. [Figure 4] 4 is a perspective view of a process for manufacturing the magnetic core shown in FIG. 3. [Diagram 5] 1A and 1B are a perspective view and a cross-sectional view of a magnetic core according to an embodiment of the present invention. [Figure 6] FIG. 6 is a process diagram of the magnetic core of FIG. 5. [Figure 7] 11A and 11B are a perspective view and a cross-sectional view of a magnetic core according to still another embodiment of the present invention. [Figure 8] 11A and 11B are a perspective view and a cross-sectional view of a magnetic core according to still another embodiment of the present invention. [Figure 9] 11A and 11B are a perspective view and a cross-sectional view of a magnetic core according to still another embodiment of the present invention. [Figure 10] 1 is a graph showing the magnetic permeability and inductance of a ferrite material and a metal ribbon material. [Figure 11] 4 is a cross-sectional image showing an epoxy ratio in an interlayer space depending on a dilution ratio of an epoxy coating liquid according to an embodiment. [Figure 12] FIG. 12 is a diagram for explaining a sample measurement region according to the embodiment. [Figure 13] FIG. 13 shows the measurement results in each region of FIG. [Figure 14] 1 is an example of an EMI filter including an inductor according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] The present invention can be modified in various ways and can have various embodiments. Specific embodiments will be illustrated and described in the drawings. However, this does not imply that the invention is limited to the specific implementation. The present invention is not intended to be limited to the specific form, and all embodiments falling within the spirit and scope of the present invention are illustrative and not restrictive. It should be understood that this invention includes any modifications, equivalents, or alternatives.

[0030] Ordinal terms such as second, first, etc. may be used to describe various components. However, these terms are not intended to limit the components. The terms are used only to distinguish one component from another. For example, Without departing from the scope of the invention, the second component may be named the first component, and similarly. The term and / or may be used to refer to multiple relationships. It includes any combination of associated items or any of a number of related items.

[0031] When an element is referred to as being "coupled" or "connected" to another element, When the component is connected to the other component, it may be directly connected or directly connected to the other component. It should be understood that there may be additional components between the components. When an element is referred to as being "directly connected" or "directly connected" to another component, In such cases, it should be understood that there are no further components in between.

[0032] In the description of the embodiments, each layer (film), region, pattern or structure is a substrate, each layer (film), region, Shaped "on" or "under" an area, pad or pattern The phrase "formed" means "formed directly" or "formed with other layers interposed therebetween." Both cases are included. The criteria for the top / upper part and the bottom / lower part of each layer are explained based on the drawings. In addition, the thickness and size of each layer (film), region, pattern, or structure in the drawings are not necessarily shown. The dimensions may be modified for clarity and convenience, and may not reflect the actual size. do not have.

[0033] The terms used in this application are merely used to describe specific embodiments and are not intended to limit the scope of the present invention. The singular term "a," "an," or "the" is used herein unless the context clearly dictates otherwise. In this application, terms such as "including" or "having" are used interchangeably throughout the specification. Any feature, number, step, operation, component, part or combination thereof described in It is intended to specify the presence of one or more other features, numbers, steps, movements, etc. The presence or possibility of addition of any operation, component, part or combination thereof is excluded in advance. It should be understood that this does not exclude

[0034] Unless otherwise defined, all terms used herein, including technical or scientific terms, , which is generally understood by those having ordinary skill in the art to which the present invention pertains. Terms as defined in commonly used dictionaries have the same meaning as those in the related art. shall be interpreted to have a meaning consistent with the meaning in the context of the Unless expressly defined, it is not to be construed in an idealized or overly formal sense.

[0035] Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings. Corresponding components are given the same reference numerals, and duplicated descriptions thereof will be omitted. do.

[0036] According to an embodiment of the present invention, the magnetic core is made of a first magnetic body and a second magnetic body made of different materials. The magnetic material may include a second magnetic body, where the second magnetic body is disposed on at least a portion of the surface of the first magnetic body. The metal ribbon may be disposed on a surface and may include multiple layers of wound metal ribbon. The second magnetic body solves the problem of weakening of the wound multi-layer metal ribbon after heat treatment. The resin material may include a resin material for bonding the wound multi-layer metal ribbon. a resin material covering the outer surface of the layer and a resin material disposed in at least a portion of the interlayer spaces of the layers. Here, the interlayer space is defined as the space between the layers that is centrifugally separated by the winding of the metal ribbon. In two ribbon layers adjacent to each other in the direction, the outer surface of the layer relatively closer to the centrifugal force is The term "space" refers to the space formed between the inner surface of the layer farther from the centrifuge. The details of the characteristics will be described later. First, referring to Figs. 5 to 8, the different embodiments of the present invention will be described. Various forms of the magnetic core made of various magnetic materials will be described. For convenience of explanation, FIG. In FIG. 7, the resin material is omitted from the illustration.

[0037] FIG. 5 is a perspective view and a cross-sectional view of a magnetic core according to an embodiment of the present invention, and FIG. 6 is a perspective view and a cross-sectional view of a magnetic core according to an embodiment of the present invention. 7 to 9 are perspective views and diagrams of a magnetic core according to another embodiment of the present invention. FIG.

[0038] Referring to FIG. 5, the magnetic core 800 includes a first magnetic body 810 and a second magnetic body 820. The first magnetic body 810 and the second magnetic body 820 are different types, and the second magnetic body 820 is the first magnetic body. The second magnetic body 820 may be disposed on at least a portion of the surface of the first magnetic body 810. It may have a higher saturation flux density than body 810.

[0039] Here, the first magnetic body 810 includes ferrite, and the second magnetic body 820 includes a metal ribbon. Here, the magnetic permeability (μ) of the ferrite can be 2,000 to 15,000. The magnetic permeability (μ) of the metal ribbon can be 100,000 to 150,000. The ferrite can be a Mn-Zn based ferrite and the metal ribbon can be a Fe based nanocrystalline metal ribbon. The Fe-based nanocrystalline metal ribbon may be a nanocrystalline metal ribbon containing Fe and Si. The thickness of the metal ribbon may be 15 μm to 20 μm, but is not necessarily limited thereto. Not done.

[0040] At this time, the first magnetic body 810 and the second magnetic body 820 are each toroidal. The second magnetic body 820 includes a second outer magnetic body 822 disposed on the outer peripheral surface S2 of the first magnetic body 810, and a second inner magnetic body 824 disposed on the inner circumferential surface S4 of the first magnetic body 810. do.

[0041] At this time, the thickness of the second outer magnetic body 822 and the second inner magnetic body 824 are the same as that of the first magnetic body. The thickness of the second outer magnetic body 822 is smaller than the thickness of the first magnetic body 810. and at least one of the ratio between the thickness of the second inner magnetic body 824 and the thickness of the first magnetic body 810. By adjusting either of these, the magnetic permeability of the magnetic core 800 can be adjusted.

[0042] To manufacture such a magnetic core, as shown in FIG. 6, two second magnetic bodies 822, Each of the second magnetic bodies 822 and 824 is a metal wire wound in multiple layers. The second magnetic bodies 822 and 824 may be formed of a resin material. The second inner magnetic body 824 corresponding to the inner peripheral surface S4 of the toroidal first magnetic body 810 is The first magnetic body 810 also has a second outer magnetic body corresponding to the outer peripheral surface S2. Of course, the relative position of each second magnetic body to the first magnetic body 810 can be determined by the magnetic field. The join order may be changed.

[0043] At this time, the outer peripheral surface S2 of the first magnetic body 810, the second outer magnetic body 822, and the first magnetic body 8 The inner circumferential surface S4 of the magnetic member 10 and the second inner magnetic body 824 may be bonded by an adhesive. The adhesive is at least one of epoxy resin, acrylic resin, silicon resin, and varnish. In this way, when different types of magnetic materials are bonded together using an adhesive, This means that performance degradation will no longer occur even when physical vibrations occur.

[0044] Here, each of the second magnetic bodies 822 and 824 is wound multiple times as shown in FIG. The metal ribbon may be laminated into multiple layers by laminating the metal ribbon. The thickness and magnetic permeability of the second magnetic bodies 822 and 824 vary depending on the number of layers. The magnetic permeability of Core 800 has changed, and the noise reduction of the EMI filter to which the magnetic core 800 is applied has been improved. Removal performance may vary.

[0045] In other words, the greater the thickness of the second magnetic bodies 822 and 824, the higher the noise removal performance may be. Using this principle, the second magnetic body 822, which is disposed in the area where the coil is wound, The thickness of 824 is the thickness of the second magnetic bodies 822 and 824 arranged in the area where the coil is not wound. The number of layers of metal ribbons stacked together can be adjusted so that the thickness is greater than the thickness.

[0046] The number of layers of the metal ribbon depends on the number of windings, the winding start point and the winding As shown in FIG. 5A, the outer circumferential surface of the first magnetic body 810 The relationship between the start point and the end point of the winding is determined based on the second outer magnetic body 822 arranged in S2. The relationship is as follows. Of course, the second outer magnetic body 822 is connected to the first magnetic body 810. Before the connection, the winding and the formation of the resin material (not shown) are completed. As described above, for the sake of convenience, the magnetic flux is generated at one point on the outer circumferential surface of the first magnetic body 810. It is assumed that winding starts based on

[0047] When winding the second outer magnetic body 822, which is a metal ribbon, When winding once from the starting point, the second outer magnetic body 822 includes one layer of metal ribbon. If you wind it twice from the start of the winding, the second outer magnetic The body 822 can include two layers of metal ribbon. If the end points of the windings are different from each other, for example, 1.5 turns from the start point of the winding When binding, the second outer magnetic body 822 is a region where a metal ribbon is laminated in one layer. This includes the area where the metal ribbon is laminated in two layers. When winding 2.5 times from the point, the second outer magnetic body 822 has two layers of metal ribbon. This includes areas where the metal ribbon is laminated in three layers and areas where the metal ribbon is laminated in three layers. If the coil is arranged in an area with a larger number of layers, the magnetic core 800 according to the embodiment of the present invention can be obtained. This can further improve the noise removal performance of the EMI filter to which it is applied.

[0048] For example, the magnetic core 800 is toroidal, and the first coil 122 is disposed on the magnetic core 800. When the first coil 124 and the second coil 125 are wound symmetrically, the first coil 124 is disposed on the outer circumferential surface of the first magnetic body 810. The first coil 122 is disposed in a region of the second outer magnetic body 822 where the number of layers is large. The area where the number of layers of the second inner magnetic body 824 arranged on the inner circumferential surface of the first magnetic body 810 is large The second coil 124 can be disposed in the region. This allows the first coil 122 and In both of the two coils 124, the number of layers stacked in the second magnetic bodies 822 and 824 is large. In the region where the number of layers is small, the first coil 122 and the second coil 124 are arranged. Since no noise is placed, high noise removal performance can be obtained.

[0049] The second outer magnetic body 822 and the second inner magnetic body 824 are assumed to have the same material and thickness. However, the present invention is not limited to this. 4 may have different materials or different magnetic permeabilities, and may have different thicknesses. This allows the magnetic core 800 to have a range of magnetic permeability.

[0050] On the other hand, as shown in FIG. 7, the height h1 of the first magnetic body 810 is greater than the height h2 of the second magnetic body 820. For this reason, in the manufacturing process of the second magnetic body 820, the high A metal ribbon with a width shorter than the length h1 can be wound up. 2 is a boundary between the upper surface S1 and the outer peripheral surface S2 of the first magnetic body 810 and a lower surface S3 of the first magnetic body 810 The second inner magnetic body 824 is not disposed at the boundary between the upper surface S1 of the first magnetic body 810 and the outer peripheral surface S2 of the first magnetic body 810. and the boundary between the lower surface S3 of the first magnetic body 810 and the inner peripheral surface S4. This prevents the boundary between the upper surface S1 and the outer peripheral surface S2 of the first magnetic body 810 from being broken. The boundary between the bottom surface S3 and the outer peripheral surface S2 of the first magnetic body 810, the top surface S1 and the inner peripheral surface S4 of the first magnetic body 810 and the boundary between the lower surface S3 and the inner peripheral surface S4 of the second outer magnetic body 810. This can prevent cracks in the insulating body 822.

[0051] Alternatively, as shown in FIG. 8, the second magnetic body 820 is provided only on the outer circumferential surface S2 of the first magnetic body 810. As shown in FIG. 9, the second magnetic body 820 may be disposed on the inner circumferential surface S of the first magnetic body 810. It may only be placed in 4.

[0052] In this way, if the magnetic core 800 contains different types of magnetic materials with different magnetic permeabilities, a wide range of frequencies can be achieved. In particular, the toroidal structure made only of Mn-Zn ferrite is Compared to a magnetic core with a conductor, the phenomenon of magnetic flux gathering on the surface is prevented, so high-frequency noise can be eliminated. The effect is large and the degree of internal saturation is low, so it can be applied to high-power products. By adjusting the magnetic permeability and volume ratio of the magnetic body 810 and the second magnetic body 820, the magnetic core 800 The performance can be adjusted.

[0053] On the other hand, referring to FIG. 10, ferrite material and metal ribbon material have different magnetic permeability by frequency. A magnetic core that contains all of these elements has a high inductance in a certain frequency range, which results in a high It can be seen that excellent noise reduction performance can be obtained.

[0054] The above describes the relative positions of the first and second magnetic bodies according to the embodiment. Next, the resin material of the second magnetic body according to an embodiment of the present invention will be described in more detail.

[0055] According to one embodiment, the resin material is formed by heat treating a metal ribbon wound into a plurality of layers. The coating can be formed by dipping the processed product in a coating liquid and then drying it. In some embodiments, the drying process may include a thermal drying process in an environment of 60° to 150°. do.

[0056] As shown in FIG. 8C, in the second magnetic body 820, the resin material R is wound around the The metal ribbon MR is placed on the outer surface (upper surface, lower surface, inner peripheral surface, outer peripheral surface) of the wound metal ribbon. It may also be placed between the bonnets (not shown).

[0057] According to one embodiment, the coating liquid is a mixture of an epoxy resin and a diluent in a predetermined ratio. The diluent may be a mixture of the epoxy resin and the epoxy resin. The following Tables 1 to 4 show the results of measuring the inductance of inductors with different ratios of epoxy resin and diluent. An example of the measurement results of the rate of decrease in performance is shown below.

[0058] [Table 1]

[0059] [Table 2]

[0060] [Table 3]

[0061] [Table 4]

[0062] Referring to Tables 1 to 4, the higher the ratio of epoxy resin, the higher the inductance reduction rate. It can be seen that the higher the diluent ratio, the smaller the inductance reduction rate. When the ratio of epoxy resin to diluent was 5:5, the inductance reduction rate was close to 30%, and When the ratio of epoxiesin to diluent was 3:7, the inductance reduction rate was close to 15%. However, the inductance when the epoxy resin to diluent ratio is 2:8 and 1:9 The decline rates are 5.72% and 4.7%, respectively, and the difference is not large, but the results show a relatively good The inductance reduction rate was shown.

[0063] Next, the strength of each diluent is compared with reference to Table 5.

[0064] [Table 5]

[0065] Table 5 shows the results of the heat treatment of a metal ribbon wound into 15 turns. The external force in g is the force required for damage when pressure is applied in the diametric direction. See Table 5. When an external force of about 70g is applied to the metal ribbon before it is soaked in the coating liquid, However, depending on the ratio of epoxy resin and diluent, the strength is increased by about 3 to 10 times. It can be seen that...

[0066] The difference in strength improvement according to the dilution ratio is due to the dilution of the coating liquid (i.e., the impregnation liquid). The viscosity of the epoxy resin varies depending on the dilution ratio, so when picking up the metal ribbon after impregnation, This is one of the reasons why a relatively large amount of epoxy remains on the outer circumference of the ribbon, but it is also because the gold wound in the impregnation liquid This is also due to the increased amount of epoxy resin penetrating into the interlayer spaces of the metal ribbon. In addition, the volume of epoxy resin increases during drying in the spaces between the layers of the wound metal ribbon. As the metal ribbon expands, microcracks increase, causing a decrease in inductance. This will be described with reference to Figs. 11 to 13. In 13, the position where the resin material is arranged in the interlayer space of the wound ribbon is 2. When the total height of the magnetic body 820 is defined as the height from the bottom surface to the top surface, They can be arranged in the region of 0% to 5% and in the region of 95% to 100% of the total height. Located in the areas of 0% to 15% and 85% to 100% of the total height in the direction from the bottom to the top. More preferably, the thickness of the slit is 0% to 30% and 70% to 10% of the total height in the direction from the bottom surface to the top surface. 00% of the total height in the direction from the bottom to the top. , the strength improvement and inductance reduction may be slight.

[0067] FIG. 11 shows the epoxy in the interlayer space depending on the dilution ratio of the epoxy coating liquid according to the embodiment. In Fig. 11, a metal reel wound into 15 turns is shown. The second magnetic body is impregnated with epoxy coating liquid with different dilution ratios, and the second magnetic body is circumferentially The cross-sections are enlarged after cutting. The end is in the centrifugal direction, and the top image shows all 15 layers of metal ribbon for each dilution ratio. The bottom image is a further enlargement showing only the five layers of metal ribbon. The circles in the bottom images indicate the areas where the epoxy resin is located. do.

[0068] Referring to FIG. 11, when the epoxy to diluent ratio is 1:9, the adjacent ribs in the centrifugal direction are The epoxy resin is located in the space between the bond layers, i.e., about 10% of the entire interlayer space. If the epoxy to diluent ratio is 2:8, the epoxy resin is located at about 25%. Also, when the epoxy to diluent ratio is 3:7, the ratio of the entire interlayer space is about 30%. When the epoxy resin is located in the epoxy resin and the ratio of epoxy to diluent is 5:5, the epoxy resin is about 50%. The epoxy resin is located.

[0069] As shown in Figure 11, the strength changes depending on the ratio of epoxy resin in the interlayer space. It becomes clear that...

[0070] Below, we will comprehensively compare the inductance reductions in Tables 1 to 4 and the strength improvement in Table 5. .

[0071] A 5:5 ratio of epoxy to diluent provides the highest strength but reduces inductance. If the ratio is too high and the epoxy to diluent ratio is 1:9, the inductance reduction rate is the lowest. The strength improvement was also low.

[0072] In addition, when the epoxy to diluent ratio was 2:8 and 1:9, the inductance The epoxy and diluent ratios were similar in terms of strength improvement, and the epoxy and diluent ratios were similar in terms of strength improvement. The 2:8 and 3:7 ratios showed similar superiority.

[0073] In other words, if the epoxy to diluent ratio is 2:8, the inductance reduction is 1: It shows a similar degree of excellence to the case of 9, and the strength shows a similar degree of excellence to the case of 3:7. As shown, this is the most preferable ratio.

[0074] Therefore, in the following, when the ratio of epoxy to diluent is 2:8, the epoxy in the interlayer space is The ratio will be explained more specifically with reference to FIGS.

[0075] FIG. 12 is a diagram for explaining a sample measurement region according to the embodiment, and FIG. These are the measurement results in each of the two areas.

[0076] FIG. 12 shows a coating liquid having a dilution ratio of 2:8 according to an embodiment of the present invention, which was then dried. A plan view of the dried second magnetic body 820 is shown. The second magnetic body 820 is divided into four areas, Area_1 to Area_4, Therefore, a cross-sectional image of one second magnetic sample is taken. The epoxy ratio in the interlayer space was measured four times for each sample, for a total of 20 measurements using five samples. A decision was made.

[0077] Figure 13 shows some sample images taken during this measurement process. The metal ribbon wound in 15 turns was then coated with an epoxy resin with a dilution ratio of 2:8. The second magnetic body soaked in the coating liquid is cut in the circumferential direction, and the cross section is enlarged. In addition, in Fig. 13, the bottom end of each image is in the centrifugal direction, and the top The images in the lower row indicate which part of the cross section the image in the lower row corresponds to, and the lower row image shows the five layers. The images are enlarged so that only the metal ribbons are visible. means the area where the epoxy resin is located.

[0078] In (a) of Fig. 13, the epoxy resin occupies 15% of the interlayer space, and in (b) of Fig. 13, The ratio is 20% in Fig. 13(c), 25% in Fig. 13(d), and 30% in Fig. 13(c). This indicates that the carboxylate occupies the

[0079] In short, when the dilution ratio is 2:8, the epoxy ratio in the interlayer space is 15% to 30%. This is a range including the maximum and minimum values, and the results of 20 measurements are shown in Table 6 below.

[0080] [Table 6]

[0081] Referring to Table 6, out of a total of 20 experiments, there were two 15% cases and four 20% cases. The dilution ratio was 100% in 10 cases, 25% in 7 cases, and 30% in 3 cases. When the ratio is 2:8, the epoxy ratio in the interlayer space is 15% to 30%, preferably 20% to 25%. %, more preferably 23% to 25%. Although not shown in the figure, the second magnetic material The thickness of the outer coating layer may be 10 μm to 40 μm, preferably 20 μm to 30 μm. If the thickness is less than 10 μm, the strength is reduced and the metal ribbon is broken. If it is larger than 40μm, the inductance reduction rate will be large and the performance will be deteriorated. may decrease.

[0082] Meanwhile, the inductor according to the above-mentioned embodiment may be included in a line filter. For example, The line filter is suitable for AC-to-DC converters. FIG. 14 shows an inductor according to an embodiment of the present invention. This is an example of an EMI filter that includes

[0083] Referring to FIG. 14, the EMI filter 2000 includes a plurality of X-capacitors Cx, a plurality of The Y-capacitor Cy and the inductor L may be included.

[0084] The X-capacitor Cx is connected between the first terminal P1 of the live line LIVE and the neutral line N Between the third terminal P3 of EUTRAL and the second terminal P2 of LIVE and the The fourth terminal P4 of the radial line NEUTRAL is disposed between the first terminal P1 and the second terminal P2.

[0085] The Y-capacitors Cy are connected to the second terminal P2 of the live line LIVE and the neutral line The fourth terminal P4 of the input NEUTRAL may be disposed in series between the fourth terminal P4 of the input NEUTRAL.

[0086] The inductor L is connected between the first terminal P1 and the second terminal P2 of the live line LIVE, It may be disposed between the third terminal P3 and the fourth terminal P4 of the neutral line NEUTRAL. Here, the inductor L can be the inductor 100 according to the above embodiment.

[0087] When common mode noise enters the EMI filter 2000, the primary inductance (P Composite impedance characteristics of Y-capacitor Cy and Y-parallel inductance Here, the primary inductor of the live line LIVE is The sense amplifier is connected to the first and second terminals P3 and P4 in an open state. The inductance between terminals P1 and P2 can be measured and the neutral line NE The primary inductance of the UTRAL is connected by opening the first and second terminals P1 and P2. n) The inductance between the third and fourth terminals P3 and P4 can be measured and obtained. can.

[0088] When differential mode noise enters the EMI filter 2000, the leakage inductance (l Composite impedance characteristics of the X-capacitor Cx and the Here, the leakage inductance of the live line LIVE is The third and fourth terminals P3 and P4 are shorted, and the first and second terminals P4 and P5 are connected to the It can be obtained by measuring the inductance between P1 and P2, and the neutral line NEUT The leakage inductance of the RAL is 3.0 V when the first and second terminals P1 and P2 are shorted. The inductance between the first terminal P1 and the fourth terminal P2 can be measured.

[0089] The inductor of the EMI filter 2000 according to the embodiment is the inductor according to the embodiment described above. This applies to the ctor.

[0090] The description of each of the above embodiments may be used interchangeably with other embodiments unless otherwise stated. It is also applicable to

[0091] The above description is centered on the embodiment, but this is merely an example and does not limit the present invention. Those skilled in the art will be able to easily understand the essential features of the present embodiment. It is understood that various modifications and applications not exemplified above are possible without departing from the scope of the invention. For example, each component specifically shown in the embodiment can be modified. The differences relating to such modifications and applications are defined in the appended claims. should be construed as being included within the scope of the present invention.

Claims

1. A first magnetic body having a toroidal shape and including ferrite; A second magnetic body disposed on an outer circumferential surface or an inner circumferential surface of the first magnetic body; Including, The second magnetic body is a multi-layered metal ribbon wound around the first magnetic body in the circumferential direction. and resinous substances, The resin material is a first resin material disposed to cover an outer surface of the plurality of layers of metal ribbon; and a second resin material disposed in at least a portion of the interlayer spaces of the plurality of layers. Duct.

2. The first magnetic body includes a Mn-Zn ferrite, and the second magnetic body includes a Fe-Si metal. Including ribbon, The second resin material is 0% of the total height of the second magnetic body in a direction from the bottom surface to the top surface. The inductor according to claim 1, which is arranged in the range of 5% to 95% and the range of 100%. Tha.

3. A thickness of the first magnetic body in a diametrical direction is greater than a thickness of the second magnetic body in a diametrical direction, The thickness of the second magnetic body in the diametrical direction is greater than the thickness of the first resin material in the diametrical direction. The inductor of claim 1 .

4. 4. The inductor according to claim 3, wherein the first resin material has a thickness of 20 μm to 30 μm. -

5. The ink jet head according to claim 3 , wherein the height of the first resin layer is greater than the height of the second magnetic body. Duct.

6. The second resin material is disposed in an amount of 15% to 30% of the interlayer spaces of the plurality of layers. The inductor of claim 1 .

7. The second resin material is disposed in an amount of 20% to 25% of the interlayer spaces of the plurality of layers. The inductor of claim 6.

8. An inductor, A capacitor; Including, The inductor is A first magnetic body having a toroidal shape and including ferrite; A second magnetic body disposed on an outer circumferential surface or an inner circumferential surface of the first magnetic body, The second magnetic body is a multi-layered metal ribbon wound around the first magnetic body in the circumferential direction. and resin substances, The resin material is a first resin material disposed to cover an outer surface of the plurality of layers of metal ribbon; A second resin material disposed in at least a portion of the interlayer spaces of the plurality of layers. MI filter.

9. The first magnetic body includes a Mn-Zn ferrite, and the second magnetic body includes a Fe-Si metal. Ribbon included The second resin material is 0% of the total height of the second magnetic body in a direction from the bottom surface to the top surface. EMI filters according to claim 8 are arranged in the range of 5% to 95% and 100%. Filter.

10. A portion of the second resin material is disposed in an area between the layers of the plurality of layers in a range of 15% to 30%. The inductor of claim 9 .

Images