JP2016025218A - Coil component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coil component capable of improving the efficiency by reducing eddy current loss.SOLUTION: A coil component 11 includes: a core 15 which has a lamination part 14 in which a magnetic material part 12 and a non-magnetic material part 13 are laminated in a magnetic path direction 23; a coil 17 of a conductor which is wound on a wound part 16 of the core 15; and a metal case 18 storing the core 15 and the coil 17. The metal case 18 has a concavity 21 at a position facing an outside surface 22 of the non-magnetic material part 13.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a coil component used in various electronic devices and electric machines.

  As coil parts, for example, a booster circuit of a motor drive device of an electric vehicle, a reactor used in various power motors, and an inductor used in power supply circuits of various electronic devices are known. The coil component includes a core made of a magnetic material and a coil made of a conductor, and performs electrical transformation using inductive reactance, blocking of harmonic current, and smoothing of direct current.

  As prior art document information relating to the invention of this application, for example, Patent Document 1 is known.

JP 2012-23083 A

  However, the conventional coil component cannot sufficiently reduce the eddy current loss caused by the leakage magnetic flux from the magnetic core, and it is difficult to improve the efficiency of the coil component. An object of this invention is to provide the coil component which can reduce an eddy current loss and can improve efficiency.

  In order to achieve the above object, a coil component includes a core having a laminated portion in which a magnetic part and a nonmagnetic part are laminated in a magnetic path direction, and a coil made of a conductor and wound around a winding part of the core. And a metal case that houses the core and the coil, and the metal case has a recess at a position facing the outer surface of the non-magnetic member.

  By having the above-described configuration, the coil component can reduce eddy current loss and improve efficiency.

(A), (b) The perspective view and exploded perspective view of the coil component in Embodiment 1 (A), (b) Sectional drawing and principal part sectional drawing of coil components in Embodiment 1 Characteristics diagram of coil component according to Embodiment 1 Characteristics diagram of coil component according to Embodiment 1 Characteristics diagram of coil component according to Embodiment 1 Characteristics diagram of coil component according to Embodiment 1 Characteristics diagram of coil component according to Embodiment 1 The exploded perspective view of the coil components in Embodiment 2 The disassembled perspective view of the other coil components in Embodiment 2. FIG.

(Embodiment 1)
1A is a perspective view of the coil component 11 according to the first embodiment, and FIG. 1B is an exploded perspective view of the coil component 11. 2A is a cross-sectional view of the cut surface in the vertical direction created by the line AA in FIG. 1A, and FIG. 2B is a cross-sectional view of the main part in which the portion B in FIG. .

  1A, 1B, 2A, and 2B, a coil component 11 includes a core 15 having a laminated portion 14 in which a magnetic body portion 12 and a nonmagnetic portion 13 are laminated, and a conductor. A coil 17 wound around the winding portion 16 of the core 15, a metal case 18 that houses the core 15 and the coil 17, a filler 19, and a terminal portion 20.

  The magnetic body portion 12 is made of soft magnetic powder having an average particle size of about 10 to 100 μm mainly composed of iron, and after insulating the surface of the soft magnetic powder, an organic binder is mixed if necessary, It is produced by pressure molding at a pressure of 5 ° C., heat treatment or sintering as necessary, and has a plurality of parts. Here, the magnetic material means a ferromagnetic material, and includes a soft magnetic material and a hard magnetic material.

  The nonmagnetic body portion 13 is made of, for example, a ceramic such as alumina or a nonmagnetic insulator such as resin, and is interposed between the magnetic body portions 12 and functions as a gap layer of the core 15. Non-magnetic materials include diamagnetic materials, paramagnetic materials, and antiferromagnetic materials. Note that the non-magnetic member 13 may be a void layer made of air.

  The core 15 includes a laminated portion 14 in which the magnetic body portion 12 and the nonmagnetic body portion 13 are laminated in the magnetic path direction 23, and a winding portion 16 that is a portion around which the coil 17 is wound, and an outer side of the coil 17. The winding part 16 and the outer part constitute a closed magnetic circuit.

  The coil 17 is formed in a spiral shape by edgewise bending a rectangular conductive wire made of a metal mainly composed of copper. The coil 17 may be a flat copper wire that is flatwise bent or may be a copper round wire that is wound. An insulating bobbin or the like may be provided between the coil 17 and the core 15 in order to ensure insulation between them.

  The case that houses the coil 17 and the core 15 uses a metal case 18 having a good heat conductivity and a shielding property in order to ensure heat dissipation and shielding performance against leakage magnetic flux. Moreover, the metal case 18 uses the thing which has light metals, such as aluminum, as a main component from a lightweight viewpoint, for example.

  By providing the concave portion 21 at a position of the metal case 18 facing the outer surface 22 of the nonmagnetic body portion 13, the coil component 11 can reduce eddy current loss due to leakage magnetic flux.

  The coil component 11 has a non-magnetic part 13 called a gap plate inside the core 15 to ensure direct current superimposition. The nonmagnetic part 13 is sandwiched between the magnetic parts 12 and stacked in the magnetic path direction 23. However, when the nonmagnetic body portion 13 is provided inside the core 15, a leakage magnetic flux is generated around the nonmagnetic body portion 13. If this leakage magnetic flux leaks to the outside of the coil component 11, an electromagnetic interference such as noise is generated. Therefore, it is necessary to shield it with the metal case 18. However, due to this leakage magnetic flux, an eddy current is generated inside the metal case 18 around the non-magnetic member 13 and energy loss occurs. The coil component 11 can reduce eddy current loss and improve the efficiency of the coil component 11 by providing the recess 21 at a position facing the outer surface 22 of the nonmagnetic body portion 13 of the metal case 18. Can do.

  This is because the opposing surface of the metal case 18 where the eddy current is generated is formed by providing the concave portion 21 at a position facing the outer surface 22 of the nonmagnetic body portion 13 of the metal case 18 through which a large amount of leakage magnetic flux passes. 12 and the laminated portion 14 of the nonmagnetic body portion 13, and the thickness of the bottom portion of the concave portion 21 of the metal case 18 is reduced, so that the generation of eddy currents in the concave portion 21 of the metal case 18 can be reduced.

  Further, when the eddy current generated in the metal case 18 other than the recess 21 flows in the metal case 18, the recess 21 is thin and has higher electric resistance than the other portions, so that the eddy current flows beyond the recess 21. By suppressing this, the path through which eddy current flows is shortened, and eddy current loss can be further reduced.

  The filler 19 is an insulator that contains an epoxy resin and a filler and hardens, and fills the space between the inner wall surface of the metal case 18, the core 15, and the coil 17. In addition to the epoxy resin, the resin constituting the filler 19 may be a silicon resin or a urethane resin.

  The terminal portion 20 is made of a conductor, connected to both ends of the coil 17 and led out of the filler 19 to obtain an electrical connection with an external circuit (not shown).

  The coil component 11 configured as described above is used as a reactor in a step-up circuit of a motor drive device of an electric vehicle and various power motors.

  Next, simulation results of eddy current loss generated in the metal case 18 of the coil component 11 under various conditions are shown in the characteristic diagrams of FIGS. The dimensions of each part of the coil component 11 used for the simulation are determined as follows.

  In FIG. 2B, the thickness of the nonmagnetic body portion 13 in the magnetic path direction 23 is G (mm), the thickness of the metal case 18 other than the concave portion 21 is T (mm), and the metal case 18 other than the core 15 and the concave portion 21. Let S (mm) be the interval between the two. The depth of the recess 21 is D (mm), the width of the recess 21 in the magnetic path direction 23 is W (mm), the thickness of the metal case 18 at the bottom of the recess 21 is R (mm), and the magnetic path direction of the recess 21 The width of 23 is W (mm), and the distance from the boundary surface on one side of the magnetic body portion 12 and the non-magnetic body portion 13 to the inner surface of the concave portion 21 on the near side is P (mm). Here, D + R = T and W = G + 2 × P.

  First, the relationship between the thickness R (mm) of the metal case 18 at the bottom of the recess 21 and the eddy current loss (W: watt) of the metal case 18 is shown in FIG.

  In the characteristic diagram of FIG. 3, the vertical axis represents eddy current loss (W: watts) of the metal case 18, and the horizontal axis represents the thickness R (mm) of the metal case 18 at the bottom of the recess 21. The coil component 11 has an operating frequency of 20 (kHz), a thickness of the nonmagnetic part 13 in the magnetic path direction 23 of G = 1 (mm), a thickness of the metal case 18 of T = 2 (mm), a core 15 and a metal. The distance from the case 18 is S = 1 (mm).

In FIG. 3, the data plot A1 is a distance P = 1 (mm), the data plot A2 is a distance P = 2 (mm), the data plot A3 is a distance P = 3 (mm), and the data plot A4 is a distance P = 4 (mm). ), The data plot A5 is the distance P = 5 (mm).
In each data plot A1 to A5, the thickness R of the metal case 18 at the bottom of the recess 21 was changed between 0.2 and 2 (mm), and the change in eddy current loss (W) was plotted. Since D = T−R, the depth D of the recess 21 is 1.8 (mm) at R = 0.2 (mm), and the depth D of the recess 21 is R = 2.0 (mm). 0 (mm).

  As can be seen from the data plots A1 to A5 in FIG. 3, the eddy current loss of the metal case 18 is achieved by setting the thickness of the metal case 18 at the bottom of the recess 21 to a range of R = 0.4 to 1.6 (mm). (W) can be reduced. Therefore, with respect to the skin depth SD = 0.58 (mm) of the aluminum metal case 18 at an operating frequency of 20 (kHz), the thickness R is 0.7 × SD (mm) or more and 2.8 × SD (mm). In the following range, the eddy current loss (W) of the metal case 18 can be reduced.

  When the thickness R is smaller than 0.7 × SD (mm), the electric resistance value at the bottom of the recess 21 is increased, and eddy current loss (W) is increased, which is not preferable. Further, if the thickness R exceeds 2.8 × SD (mm), the eddy current loss (W) cannot be reduced in the recess 21, and eddy currents generated outside the recess 21 easily pass through the metal case 18. This is not preferable because the eddy current loss (W) increases. More preferably, the eddy current loss (W) of the metal case 18 can be further greatly reduced in the range where the thickness R is SD (mm) or more and 2 × SD (mm) or less.

  Usually, at a frequency as high as 20 kHz, the current density of the eddy current is high on the surface of the metal case 18 due to the skin effect, and becomes low when it is away from the surface. Even in the part where the eddy current away from the surface flows, it is preferable to reduce the loss by suppressing the electric resistance value, and the upper limit of the thickness R (mm) is 2.8 × SD (mm), more preferably 2 ×. It is good to set to SD (mm).

  Next, when the thickness G (mm) of the nonmagnetic part 13 in the magnetic path direction 23 is increased from G = 1 (mm) shown in the characteristic diagram of FIG. FIG. 4 shows the relationship between the thickness R (mm) of the metal case 18 at the bottom and the eddy current loss (W: watts) of the metal case 18.

  In the characteristic diagram of FIG. 4, the vertical axis represents the eddy current loss (W: watts) of the metal case 18, and the horizontal axis represents the thickness R (mm) of the metal case 18 at the bottom of the recess 21. The coil component 11 has an operating frequency of 20 (kHz), a thickness of the nonmagnetic portion 13 in the magnetic path direction 23 of G = 2 (mm), a thickness of the metal case 18 of T = 2 (mm), a core 15 and a metal The distance from the case 18 is S = 1 (mm).

  In FIG. 4, the data plot B1 is a distance P = 1 (mm), the data plot B2 is a distance P = 2 (mm), the data plot B3 is a distance P = 3 (mm), and the data plot B4 is a distance P = 4 (mm). ). In each data plot B1 to B4, the thickness R of the metal case 18 at the bottom of the recess 21 was changed between 0.2 and 2 (mm), and the change in eddy current loss (W) was plotted. The depth D of the recess 21 is 1.8 (mm) at R = 0.2 (mm), and the depth D of the recess 21 is 0 (mm) at R = 2.0 (mm).

  As can be seen from the data plots B1 to B4 in FIG. 4, the eddy current loss of the metal case 18 is achieved by setting the thickness of the metal case 18 at the bottom of the recess 21 to a range of R = 0.4 to 1.6 (mm). (W) could be reduced.

  Thus, even in the case of FIG. 4 where the thickness G (mm) in the magnetic path direction 23 of the nonmagnetic portion 13 is increased from 1 (mm) to 2 (mm), as in the characteristic diagram of FIG. The thickness R is in the range of 0.7 × SD to 2.8 × SD (mm) with respect to the skin depth SD = 0.58 (mm) of the aluminum metal case 18 at an operating frequency of 20 (kHz). Thereby, the eddy current loss (W) of the metal case 18 can be reduced. In particular, when the thickness R is in the range of SD to 2 × SD (mm), the eddy current loss (W) of the metal case 18 can be further greatly reduced.

  Next, the bottom of the recess 21 when the interval S (mm) between the core 15 and the metal case 18 is increased from S = 1 (mm) shown in the characteristic diagram of FIG. 3 to S = 2 (mm). FIG. 5 shows the relationship between the thickness R (mm) of the metal case 18 and the eddy current loss (W: watts) of the metal case 18.

  In the characteristic diagram of FIG. 5, the vertical axis represents the eddy current loss (W: watts) of the metal case 18, and the horizontal axis represents the thickness R (mm) of the metal case 18 at the bottom of the recess 21. The coil component 11 has an operating frequency of 20 (kHz), a thickness of the nonmagnetic part 13 in the magnetic path direction 23 of G = 1 (mm), a thickness of the metal case 18 of T = 2 (mm), a core 15 and a metal. The distance from the case 18 is S = 2 (mm).

  In FIG. 5, the data plot C1 is a distance P = 1 (mm), the data plot C2 is a distance P = 2 (mm), the data plot C3 is a distance P = 3 (mm), and the data plot C4 is a distance P = 4 (mm). ), The data plot C5 is the distance P = 5 (mm).

  In each data plot C1 to C5, the thickness R of the metal case 18 at the bottom of the recess 21 was changed between 0.2 and 2 (mm), and the change in eddy current loss (W) was plotted. The depth D of the recess 21 is 1.8 (mm) at R = 0.2 (mm), and the depth D of the recess 21 is 0 (mm) at R = 2.0 (mm).

  As can be seen from the data plots C1 to C5 in FIG. 5, the eddy current loss of the metal case 18 (by reducing the thickness R of the metal case 18 at the bottom of the recess 21 to a range of 0.4 to 1.6 (mm) ( W) could be reduced.

  Thus, even in the case of FIG. 5 in which the distance S (mm) between the core 15 and the metal case 18 is changed from 1 (mm) to 2 (mm), as in the characteristic diagram of FIG. The thickness R should be in the range of 0.7 × SD to 2.8 × SD (mm) with respect to the skin depth SD = 0.58 (mm) of the aluminum metal case 18 at an operating frequency of 20 (kHz). Therefore, the eddy current loss (W) of the metal case 18 can be reduced. In particular, when the thickness R is in the range of SD to 2 × SD (mm), the eddy current loss (W) of the metal case 18 can be further greatly reduced.

  Next, FIG. 6 shows the relationship between the eddy current loss (W: watts) of the metal case 18 and the thickness R (mm) of the metal case 18 at the bottom of the recess 21 in the difference in the operating frequency of the coil component 11.

  In the characteristic diagram of FIG. 6, the vertical axis represents the eddy current loss (W: watts) of the metal case 18, and the horizontal axis represents the thickness R (mm) of the metal case 18 at the bottom of the recess 21. In the coil component 11, the thickness of the non-magnetic part 13 in the magnetic path direction 23 is G = 1 (mm), the thickness of the metal case 18 is T = 3 (mm), and the distance between the core 15 and the metal case 18 is S = 1 (mm).

  In FIG. 6, the operating frequency of the coil component 11 is 1 (kHz) for data plot D1, 5 (kHz) for data plot D2, 10 (kHz) for data plot D3, 20 (kHz) for data plot D4, and data plot. D4 is 100 (kHz). In each data plot D1 to D5, the thickness R of the metal case 18 at the bottom of the recess 21 was changed between 0.2 and 2 (mm), and the change in eddy current loss (W) was plotted. Note that the depth D of the recess 21 is 2.8 (mm) at R = 0.2 (mm), and the depth D of the recess 21 is 1 (mm) at R = 2.0 (mm). The skin depth of the metal case 18 made of aluminum is 2.59 (mm) when the operating frequency is 1 (kHz), 1.16 (mm) when the operating frequency is 5 (kHz), and the operating frequency is 10 It is 0.82 (mm) when (kHz), 0.58 (mm) when the operating frequency is 20 (kHz), and 0.26 (mm) when the operating frequency is 100 (kHz).

  As can be seen from the data plots D1 to D4 in FIG. 6, even when the operating frequency of the coil component 11 is different, similarly to the characteristic diagram of FIG. 3, the coil component 11 has a skin depth of the aluminum metal case 18 at each operating frequency. The eddy current loss (W) of the metal case 18 can be reduced by setting the thickness R in the range of 0.7 × SD to 2.8 × SD (mm). In particular, when the thickness R is in the range of SD to 2 × SD (mm), the eddy current loss (W) of the metal case 18 can be further greatly reduced.

  Next, the eddy current loss (W: Watt) of the metal case 18 with respect to the distance P (mm) from the boundary surface on one side of the magnetic body portion 12 and the nonmagnetic body portion 13 to the inner surface of the concave portion 21 on the near side. The relationship is shown in FIG. 7 by changing the distance S (mm) between the core 15 and the metal case 18.

  In the characteristic diagram of FIG. 7, the vertical axis represents the eddy current loss (W: watts) of the metal case 18, and the horizontal axis represents the inside of the recess 21 on the side closer to the boundary surface between the magnetic body portion 12 and the nonmagnetic body portion 13. The distance P (mm) to the side surface. The coil component 11 has an operating frequency of 20 (kHz), a thickness of the metal case 18 at the bottom of the recess 21 of R = 0.8 (mm), and a thickness of the nonmagnetic portion 13 in the magnetic path direction 23 of G = 1 ( mm) and the thickness of the metal case 18 is T = 2 (mm).

  In FIG. 7, the data plot E1 is a distance S = 1 (mm) between the core 15 and the metal case 18, and the data plot E2 is a distance S = 2 (mm) between the core 15 and the metal case 18. In each of the data plots E1 and E2, the horizontal axis represents the distance P from the boundary surface on one side of the magnetic body portion 12 and the nonmagnetic body portion 13 to the inner surface of the concave portion 21 on the near side of 0.5 to 5 (mm). And the change in eddy current loss (W) was plotted. Since W = G + 2 × P, the width W of the recess 21 varies in the range of 2 to 11 (mm).

  As can be seen from the data plots E1 and E2 in FIG. 7, the distance P is 1 (mm) or more, that is, the width W of the recess is 3 (mm) or more, and the width W of the recess is the magnetic path direction of the nonmagnetic body portion 13. By making the thickness G more than three times the thickness G of 23, the eddy current loss (W) of the metal case 18 can be reduced.

  Further, the distance P is 1.5 (mm) or more, that is, the width W of the recess is 4 (mm) or more, and the width W of the recess is 4 times or more the thickness G in the magnetic path direction 23 of the nonmagnetic body portion 13. By doing so, the eddy current loss (W) of the metal case 18 can be further reduced.

  As described above, the coil component 11 includes the core 15 having the laminated portion 14 in which the magnetic body portion 12 and the nonmagnetic body portion 13 are laminated in the magnetic path direction 23, and the winding portion 16 of the core 15 made of a conductor. The coil 17 is provided with a wound coil 17 and a metal case 18 that houses the core 15 and the coil 17. The metal case 18 has a recess 21 at a position facing the outer surface 22 of the nonmagnetic body 13, thereby leaking. Eddy current loss generated in the metal case 18 due to magnetic flux can be reduced, and the efficiency can be improved.

  Moreover, the coil component 11 can reduce the eddy current loss by a leakage magnetic flux effectively by making the width | variety of the recessed part 21 larger than the width | variety of the thickness direction in the outer surface 22 of the nonmagnetic body part 13. FIG.

  In addition, the coil component 11 can effectively reduce the eddy current loss due to the leakage magnetic flux by making the width of the recess 21 more than three times the width of the outer surface 22 of the nonmagnetic body portion 13 in the thickness direction. it can.

  Moreover, the coil component 11 can further reduce the eddy current loss due to the leakage magnetic flux by setting the width of the concave portion 21 to four times or more the width of the outer surface 22 of the nonmagnetic body portion 13 in the thickness direction.

  Moreover, the coil component 11 can effectively reduce the eddy current loss due to the leakage magnetic flux by providing the concave portion 21 at a position covering the outer surface 22 of the nonmagnetic body portion 13.

  Here, the position covering the outer surface 22 of the nonmagnetic body portion 13 means that the opening of the recess 21 is located on the inner surface of the metal case 18 so as to cover a region facing the outer surface 22 of the nonmagnetic body portion 13. It is preferable that the outer surface 22 of the non-magnetic member 13 is positioned so as to face the center of the opening of the recess 21. More preferably, the central portion of the outer surface 22 of the nonmagnetic body portion 13 is positioned so as to face the central portion of the width of the opening of the recess 21.

  Further, the coil component 11 is configured such that the thickness of the metal case 18 at the bottom of the recess 21 is 0.7 times or more and 2.8 times or less the skin thickness of the material of the metal case 18 at the operating frequency of the coil component 11. The eddy current loss due to the leakage magnetic flux can be effectively reduced.

  In addition, the coil component 11 has a leakage flux caused by setting the thickness of the metal case 18 at the bottom of the recess 21 to 1 to 2 times the skin thickness of the material of the metal case 18 at the operating frequency of the coil component 11. Eddy current loss can be further effectively reduced.

(Embodiment 2)
FIG. 8 is an exploded perspective view of the coil component 31 according to the second embodiment. In the coil component 31 in the second embodiment, the same components as those in the coil component 11 in the first embodiment are denoted by the same reference numerals and description thereof is omitted. The coil component 31 is different from the coil component 11 in the direction of the core 15 and the coil 17 when housed in the metal case 18.

  Similar to the coil component 11, the coil component 31 has the concave portion 21 at a position facing the outer surface 22 of the nonmagnetic body portion 13 of the metal case 18, thereby reducing eddy current loss due to leakage magnetic flux. . The dimensions of the recess 21 in the coil component 31 can be determined in the same manner as the coil component 11 in the first embodiment.

  Here, the outer surface 22 of the non-magnetic member 13 includes the downward outer surface 22 that faces the inner bottom surface of the metal case 18. In the coil component 31, the metal case 18 similarly has a recess 21 on the inner bottom surface at a position facing the downward outer surface 22 of the nonmagnetic body portion 13.

  FIG. 9 is an exploded perspective view of another coil component 32 according to the second embodiment. In the other coil parts 32 in the second embodiment, the same reference numerals are given to the components common to the coil parts 11 in the first embodiment, and the description thereof is omitted. The coil part 32 is different from the coil part 11 in the direction of the core 15 and the coil 17 when housed in the metal case 18.

  Similar to the coil component 11, the coil component 32 has the recess 21 at a position facing the outer surface 22 of the nonmagnetic body portion 13 of the metal case 18, thereby reducing eddy current loss due to leakage magnetic flux. . The dimension of the recess 21 in the coil component 32 can be determined in the same manner as the coil component 11 in the first embodiment.

  Similar to the coil component 31, in the coil component 32, the metal case 18 also has a recess 21 on the inner bottom surface at a position facing the downward outer surface 22 of the nonmagnetic body portion 13.

  The coil components 11, 31, and 32 described in the first and second embodiments can be applied as elements other than the reactor, such as inductor elements used in various electronic devices.

  In the embodiments, terms indicating directions such as “upper side”, “lower side”, and “vertical” indicate relative directions that depend only on the relative positional relationship of the components, and are absolute directions such as the vertical direction. It does not indicate.

  The coil component according to the present invention is useful as an inductor element for various electronic devices and as a reactor for operating electric motors such as power motors and various machine tools for electric vehicles.

11, 31, 32 Coil parts 12 Magnetic body part 13 Non-magnetic body part 14 Laminated part 15 Core 16 Winding part 17 Coil 18 Metal case 19 Filler 20 Terminal part 21 Recessed part 22 Outer side surface 23 Magnetic path direction

Claims (7)

A core having a laminated portion in which a magnetic part and a non-magnetic part are laminated in a magnetic path direction;
A coil made of a conductor and wound around the winding portion of the core;
A metal case for housing the core and the coil;
The said metal case is a coil component which has a recessed part in the position facing the outer surface of the said non-magnetic-material part. The coil component according to claim 1, wherein a width of the concave portion is larger than a width in a thickness direction on an outer surface of the nonmagnetic body portion. 2. The coil component according to claim 1, wherein a width of the concave portion is three times or more a width in a thickness direction on an outer surface of the nonmagnetic body portion. The coil component according to claim 1, wherein a width of the concave portion is four times or more a width in a thickness direction on an outer surface of the nonmagnetic body portion. The coil component according to claim 1, wherein the concave portion is provided at a position covering an outer surface of the nonmagnetic body portion. The coil component according to claim 1, wherein the thickness of the metal case at the bottom of the recess is 0.7 times or more and 2.8 times or less the skin thickness of the material of the metal case at the operating frequency of the coil component. 2. The coil component according to claim 1, wherein the thickness of the metal case at the bottom of the recess is 1 to 2 times the skin thickness of the material of the metal case at the operating frequency of the coil component.

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