Magnetically coupled coil component and method for manufacturing the same

Abstract

This invention provides a magnetically coupled coil component that achieves high dimensional accuracy in the spacing between two coil conductors. [Solution] The magnetically coupled coil component 1 comprises first and second coil conductors 25 and 35, a first base portion 11 covering the first coil conductor, a second base portion 12 covering the second coil conductor, a first external electrode 21 connected to one end of the first coil conductor, a second external electrode 22 connected to the other end of the first coil conductor, a third external electrode 23 connected to one end of the second coil conductor, and a fourth external electrode 24 connected to the other end of the second coil conductor. The first and second coil conductors each have first and second circumferential portions 25a and 35a extending in the circumferential direction around the coil axis. The first base portion has a main body portion 11a and one or more protrusions. If the end face of the main body portion in the direction toward the second coil conductor along the coil axis is considered the first surface, then the one or more protrusions protrude from the first surface of the main body portion. The second coil conductor is arranged such that the second circumferential portion is in contact with at least one protrusion.

Description

Technical Field

[0001] The disclosure in this specification mainly relates to a magnetically coupled coil component and a method for manufacturing a magnetically coupled coil component.

Background Art

[0002] A magnetically coupled coil component has two or more coil elements that are magnetically coupled to each other. The magnetically coupled coil component is used, for example, as a common mode choke coil, a transformer, or a coupled inductor.

[0003] In the magnetically coupled coil component described in Japanese Patent Application Laid-Open No. 2016-131208, two coil conductors are arranged along the coil axis.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In a magnetically coupled coil component in which two coil conductors are arranged along the coil axis, the distance between the two coil conductors in the coil axis direction has a great influence on the coupling coefficient. Therefore, in order to achieve a desired coupling coefficient in such a magnetically coupled coil component, high dimensional accuracy is required for the distance between the coil conductors.

[0006] In the magnetically coupled coil component described in Patent Document 1, each of the two coil components is constructed as a laminate, and these laminates are joined together with a non-magnetic adhesive (joint portion 13). As a result, the spacing between the coil conductors changes depending on the thickness of the adhesive. The thickness of the adhesive interposed between the two laminates is easily affected by variations in thickness during application and the force applied to press one laminate against the other after the adhesive has been applied, making it difficult to precisely control the thickness of the adhesive joining the two laminates. Furthermore, the non-magnetic adhesive can also be a factor in reducing the inductance value.

[0007] Furthermore, in the magnetically coupled coil component of Patent Document 1, the distance between two coil conductors is determined by the number of insulating layers (for example, insulating layers 11d1 to 11d3 shown in Figure 3) located at the ends of each laminate in the lamination direction, and the thickness of each insulating layer. Since it is difficult to keep the thickness of the sheet-like insulating layers constant, in the magnetically coupled coil component of Patent Document 1, where the distance between coil conductors is determined by the sum of the thicknesses of multiple insulating layers, it is difficult to obtain high dimensional accuracy for the distance between coil conductors.

[0008] The object of the inventions disclosed herein is to solve or alleviate at least some of the problems described above. One specific object of the present invention is to provide a magnetically coupled coil component that can achieve high dimensional accuracy in the spacing between two coil conductors. The various inventions disclosed herein may be collectively referred to as “the present invention.”

[0009] Any other object of the present invention will be made clear throughout the specification. The invention described in the claims may solve problems other than those identified in the "problems to be solved by the invention." [Means for solving the problem]

[0010] A magnetically coupled coil component according to one aspect of the present invention comprises a first coil conductor, a second coil conductor, a first base portion covering the first coil conductor, a second base portion covering the second coil conductor, a first external electrode connected to one end of the first coil conductor, a second external electrode connected to the other end of the first coil conductor, a third external electrode connected to one end of the second coil conductor, and a fourth external electrode connected to the other end of the second coil conductor. The first coil conductor has a first circumferential portion extending in the circumferential direction around the coil axis. The second coil conductor has a second circumferential portion extending in the circumferential direction around the coil axis. The first base portion has a main body portion and at least one protruding portion. The end face of the main body portion in a first direction along the coil axis is defined as the first surface. At least one protruding portion protrudes from the first surface of the main body portion. The second coil conductor is arranged such that the second circumferential portion is in contact with at least one protruding portion. [Effects of the Invention]

[0011] According to one aspect of the present invention, high dimensional accuracy can be obtained regarding the spacing between two coil conductors in a magnetically coupled coil component. [Brief explanation of the drawing]

[0012] [Figure 1] This is a schematic diagram of a magnetically coupled coil component according to one embodiment of the present invention. [Figure 2] This is a schematic perspective view showing a magnetically coupled coil component according to one embodiment of the present invention. [Figure 3] Figure 2 is a transmission view of a magnetically coupled coil component seen through a frontal view. [Figure 4] This figure schematically shows the first base portion and the second coil conductor provided in the magnetically coupled coil component shown in Figure 2. [Figure 5] This is a flowchart illustrating the manufacturing process of a magnetically coupled coil component according to one embodiment of the present invention. [Figure 6a] This is a schematic diagram illustrating the process of placing the first coil conductor into a molding die, which is part of the manufacturing method for coil components. [Figure 6b]This is a schematic diagram illustrating the process of forming the first base part in the manufacturing method of coil components. [Figure 7] This is a schematic diagram showing the process of assembling the second coil conductor to the first base. [Figure 8] This is a schematic diagram showing the process of assembling the second coil conductor to the first base. [Figure 9] This is a schematic diagram showing a modified example of the first base part. [Modes for carrying out the invention]

[0013] Various embodiments of the present invention will be described below with reference to the drawings as appropriate. Components common to multiple drawings are denoted by the same reference numerals throughout the drawings. Note that, for the sake of clarity, the drawings are not necessarily drawn to an exact scale. The embodiments described below do not necessarily limit the invention as defined in the claims. The elements described in the embodiments below are not necessarily essential to the solution of the invention.

[0014] First, with reference to Figure 1, an outline of a magnetically coupled coil component 1 according to one embodiment of the present invention will be described. As schematically shown in Figure 1, the magnetically coupled coil component 1 according to one embodiment of the present invention comprises a base body 10, a first coil conductor 25 disposed within a first base body portion 11 of the base body 10, and a second coil conductor 35 disposed within a second base body portion 12 of the base body 10. The magnetically coupled coil component 1 can be used as a choke coil, a transformer, a coupled inductor, and various other magnetically coupled coil components. When the magnetically coupled coil component 1 is used, the first coil conductor 25 is magnetically coupled with the second coil conductor 35. In Figure 1, for the sake of simplicity in the illustration, the external electrodes are not shown.

[0015] The first coil conductor 25 has a first turn portion 25a that extends in the circumferential direction around the coil axis Ax1. The second coil conductor 35 has a second turn portion 35a that extends in the circumferential direction around the coil axis Ax1. The first coil conductor 25 and the second coil conductor 35 are arranged along the coil axis Ax1. In the following description, the direction along the coil axis Ax1 is referred to as the "axial direction". Also, in FIG. 1, the direction from the first coil conductor 25 toward the second coil conductor 35 along the coil axis Ax1 is referred to as the "first direction", and the direction opposite to the first direction is referred to as the "second direction".

[0016] The base body 10 is partitioned into a first base body portion 11 and a second base body portion 12. The first base body portion 11 has a main body portion 11a that covers the first coil conductor 25, and a protruding portion 11b that protrudes in the first direction from the first surface 11a1 of the main body portion 11a. The first surface 11a1 is the end surface of the main body portion 11a in the first direction. The main body portion 11a is also filled inside the radial direction of the first turn portion 25a of the first coil conductor 25. The protruding portion 11b is connected to the portion inside the radial direction of the first turn portion 25a in the main body portion 11a. The first base body portion 11 can be manufactured with high dimensional accuracy, for example, by using a mold.

[0017] The first turn portion 25a has a first coil surface 25a1. The first coil surface 25a1 is the end surface of the first turn portion 25a in the first direction. In one embodiment, the first coil surface 25a1 of the first turn portion 25a is exposed from the first surface 11a1 of the main body portion 11a. In other words, the main body portion 11a covers the first coil conductor 25 such that the first coil surface 25a1 of the first turn portion 25a is exposed from the first surface 11a1. The first coil surface 25a1 may be flush with the first surface 11a1.

[0018] The second coil conductor 35 is disposed in the second base body portion 12 such that the second turn portion 35a contacts the protruding portion 11b. In the illustrated embodiment, the second coil surface 35a1 of the second turn portion 35a directly contacts the protruding portion 11b. The second coil surface 35a1 is the end surface of the second turn portion 35a in the second direction.

[0019] With this magnetically coupled coil component 1, the distance between the first coil conductor 25 and the second coil conductor 35 in the axial direction can be made equal to the axial dimension D1 of the protrusion 11b. As described above, since the first base portion 11 is manufactured with high dimensional accuracy, high dimensional accuracy can also be obtained for the axial dimension D1 of the protrusion 11b, which is part of the first base portion 11. Furthermore, since the second coil conductor 35 is arranged so that the second coil surface 35a1 of the second circumferential portion 35a is in contact with the protrusion 11b, no other members or compositions (e.g., adhesive) other than the protrusion 11b are interposed between the first coil conductor 25 and the second coil conductor 35. In this way, in the magnetically coupled coil component 1, high dimensional accuracy can be obtained for the distance between the first coil conductor 25 and the second coil conductor 35 by making the distance between the first coil conductor 25 and the second coil conductor 35 equal to the axial dimension D1 of the protrusion 11b.

[0020] In one embodiment, the protrusion 11b is formed integrally with the main body 11a. In other words, the main body 11a and the protrusion 11b have a one-piece structure. If the main body 11a and the protrusion 11b are joined with an adhesive, dimensional errors may occur in the spacing between the first coil conductor 25 and the second coil conductor 35 depending on the variation in the thickness of the adhesive. By forming the first base 11 such that the main body 11a and the protrusion 11b have a one-piece structure, dimensional errors caused by the joining means between the main body 11a and the protrusion 11b can be eliminated, and thus even higher dimensional accuracy can be obtained for the spacing between the first coil conductor 25 and the second coil conductor 35.

[0021] Next, the dimensions of the projection 11b in the radial direction centered on the coil axis Ax1 will be described. The radial direction centered on the coil axis Ax1 intersects perpendicularly with the axial direction along the coil axis Ax1. The projection 11b has an outer dimension D2 in the radial direction. In one embodiment, the outer dimension D2 of the projection 11b is larger than the inner diameter dimension D3 of the first circumferential portion 25a.

[0022] In one embodiment, the outer dimension D2 of the protrusion 11b is larger than the inner diameter D4 of the second circumferential portion 35a. By making the outer dimension D2 of the protrusion 11b larger than the inner diameter D4 of the second circumferential portion 35a, the second coil surface 35a1 of the second circumferential portion 35a can be reliably seated on the end face of the protrusion 11b in the first direction.

[0023] In one embodiment, the external dimensions D2 of the protrusion 11b are smaller than the external dimensions D5 of the second surrounding portion 35a. If the external dimensions D2 of the protrusion 11b are too large, the radial width of the surrounding portion 12a of the second base portion 12 that surrounds the protrusion 11b from the radially outside will be reduced. By making the external dimensions D2 of the protrusion 11b smaller than the external dimensions D5 of the second surrounding portion 35a, the radial width of the surrounding portion 12a can be increased by that amount, thereby ensuring the strength of the surrounding portion 12a.

[0024] Next, the magnetic coupling coil component 1 will be described in more detail with further reference to Figures 2 and 3. Figure 2 is a perspective view of the magnetic coupling coil component 1 according to one embodiment of the present invention, and Figure 3 is a transmission view of the magnetic coupling coil component seen through from the front.

[0025] As shown in the figure, the magnetically coupled coil component 1 comprises a base body 10, a first coil conductor 25, and a second coil conductor 35, as well as a first external electrode 21 connected to one end of the first coil conductor 25, a second external electrode 22 connected to the other end of the first coil conductor 25, a third external electrode 23 connected to one end of the second coil conductor 35, and a fourth external electrode 24 connected to the other end of the second coil conductor 35. The first external electrode 21, the second external electrode 22, the third external electrode 23, and the fourth external electrode 24 are arranged on the surface of the base body 10 so as to be spaced apart from each other. The first external electrode 21 and the third external electrode 23 are provided on the base body 10 so as to be spaced apart from each other in the W-axis direction. The magnetically coupled coil component 1 is mounted on a circuit board via the first external electrode 21, the second external electrode 22, the third external electrode 23, and the fourth external electrode 24. The circuit board on which the magnetically coupled coil component 1 is mounted can be mounted on various electronic devices. Electronic devices that may incorporate circuit boards include smartphones, tablets, game consoles, automotive electronics, servers, and various other electronic devices.

[0026] In one embodiment, the base body 10 is constructed from an insulating material in a rectangular parallelepiped shape. For example, the dimensions (length) of the magnetically coupled coil component 1 in the L-axis direction are in the range of 0.5 mm to 6.0 mm, the dimensions (width) in the W-axis direction are in the range of 0.5 mm to 10 mm, and the dimensions (height) in the T-axis direction are in the range of 0.3 mm to 6 mm. In one embodiment, the length dimension of the magnetically coupled coil component 1 may be greater than the width dimension. In this specification, "rectangular parallelepiped" or "rectangular parallelepiped shape" does not mean only a "rectangular parallelepiped" in a mathematically strict sense. As will be described later, the corners and / or edges of the base body 10 may be curved. The dimensions and shape of the base body 10 are not limited to those explicitly stated herein.

[0027] The base body 10 has a first main surface 10a, a second main surface 10b, a first end surface 10c, a second end surface 10d, a first side surface 10e, and a second side surface 10f. The first main surface 10a and the second main surface 10b each form the surfaces at both ends of the base body 10 in the height direction (T-axis direction), the first end surface 10c and the second end surface 10d each form the surfaces at both ends of the base body 10 in the length direction (L-axis direction), and the first side surface 10e and the second side surface 10f each form the surfaces at both ends of the base body 10 in the width direction (W-axis direction). The first main surface 10a and the second main surface 10b face each other in the T-axis direction. As shown in Figure 1, the first main surface 10a is on the upper side of the base body 10, so the first main surface 10a is sometimes called the "top surface". Similarly, the second main surface 10b is sometimes called the "bottom surface" or "bottom surface".

[0028] In the illustrated embodiment, the first external electrode 21, the second external electrode 22, the third external electrode 23, and the fourth external electrode 24 are provided on the upper surface 10a of the base body 10. When mounting the magnetically coupled coil component 1 on a circuit board, the upper surface 10a is positioned to face the circuit board. For this reason, the upper surface 10a of the base body 10 is sometimes called the "mounting surface". In one embodiment, the first external electrode 21, the second external electrode 22, the third external electrode 23, and the fourth external electrode 24 are all provided on the base body 10 so as to be in contact only with the upper surface 10a. In another embodiment, at least one of the first external electrode 21, the second external electrode 22, the third external electrode 23, and the fourth external electrode 24 may extend to a surface other than the upper surface 10a of the base body 10. For example, the first external electrode 21 may extend so as to be in contact not only with the upper surface 10a but also with the second side surface 10f.

[0029] The upper surface 10a and the lower surface 10b are separated by the height dimension of the base body 10, the first end surface 10c and the second end surface 10d are separated by the length dimension of the base body 10, and the first side surface 10e and the second side surface 10f are separated by the width dimension of the base body 10. In this specification, unless otherwise interpreted in context, the "length" direction, "width" direction, and "thickness" (or "height") direction of the magnetically coupled coil component 1 are the L-axis direction, W-axis direction, and T-axis direction of Figure 1, respectively.

[0030] The substrate 10 is made from an insulating material with excellent insulating properties. The substrate 10 may also be made from a magnetic material. As the magnetic material for the substrate 10, a soft magnetic alloy material, a composite magnetic material in which magnetic particles are dispersed in a resin, a ferrite material, or any other known magnetic material can be used.

[0031] In the illustrated embodiment, the first coil conductor 25 and the second coil conductor 35 are arranged along the coil axis Ax1. The coil axis Ax1 is a virtual axis extending along the T-axis direction. A protrusion 11b, which is part of the insulating substrate 10, is interposed between the first coil conductor 25 and the second coil conductor 35. Therefore, the first coil conductor 25 and the second coil conductor 35 are positioned within the substrate 10 at a distance D1 from the protrusion 11b in the axial direction along the coil axis Ax1. The axial dimension D1 of the protrusion 11b can be, for example, 1 / 100 to 1 / 10 of the height dimension of the substrate 10. The axial dimension D1 of the protrusion 11b can be, for example, 0.05 to 0.2 mm. The radial outer dimension D2 of the protrusion 11b can be 1.8 mm to 3.5 mm.

[0032] The first coil conductor 25 has a first circumferential portion 25a, a first lead-out portion 25b connecting one end of the first circumferential portion 25a to the first external electrode 21, and a second lead-out portion 25c connecting the other end of the first circumferential portion 25a to the second external electrode 22.

[0033] The first circumferential portion 25a extends circumferentially around the coil axis Ax, which extends along the T-axis. The first circumferential portion 25a is provided inside the base body 10 so as to face the upper surface 10a of the base body 10. The first lead-out portion 25b extends from one end of the first circumferential portion 25a along the T-axis to the upper surface 10a of the base body 10. One end of the first lead-out portion 25b is exposed to the outside of the base body 10 from the upper surface 10a of the base body 10. The first lead-out portion 25b is connected to the first external electrode 21 at the exposed surface exposed from the upper surface 10a. The second lead-out portion 25c extends from the other end of the first circumferential portion 25a along the T-axis to the upper surface 10a of the base body 10. One end of the second lead-out portion 25c is exposed to the outside of the base body 10 from the upper surface 10a of the base body 10. The second lead-out portion 25c is connected to the second external electrode 22 at the exposed surface exposed from the upper surface 10a.

[0034] The second coil conductor 35 has a second circumferential portion 35a, a third lead portion 35b connecting one end of the second circumferential portion 35a to the third external electrode 23, and a fourth lead portion 35c connecting the other end of the second circumferential portion 35a to the fourth external electrode 24.

[0035] The second circumferential portion 35a extends circumferentially around the coil axis Ax1. The second circumferential portion 35a is positioned between the first circumferential portion 25a and the lower surface 10b of the base body 10. The second circumferential portion 35a faces the lower surface 10a of the base body 10. The third lead-out portion 35b extends from one end of the second circumferential portion 35a along the T-axis to the upper surface 10a of the base body 10. One end of the third lead-out portion 35b is exposed to the outside of the base body 10 from the upper surface 10a of the base body 10. The third lead-out portion 35b is connected to the third external electrode 23 at the exposed surface exposed from the upper surface 10a. The fourth lead-out portion 35c extends from the other end of the second circumferential portion 35a along the T-axis to the upper surface 10a of the base body 10. One end of the fourth lead-out portion 35c is exposed to the outside of the base body 10 from the upper surface 10a of the base body 10. The fourth lead-out portion 35c is connected to the fourth external electrode 24 at the exposed surface that is exposed from the upper surface 10a.

[0036] The first coil conductor 25 and the second coil conductor 35 are made of a metal material with excellent conductivity. For example, Ag or Cu can be used as the metal material for the first coil conductor 25 and the second coil conductor 35. For example, the first coil conductor 25 and the second coil conductor 35 can be manufactured from a metal strip or wire using a winding machine. The surfaces of the first coil conductor 25 and the second coil conductor 35 may be covered with an insulating coating (not shown) made of an insulating material with excellent insulating properties. The insulating coating may be an oxide film formed on the surfaces of the first coil conductor 25 and the second coil conductor 35 during the heat treatment in the manufacturing process of the magnetically coupled coil component 1. The insulating coating may be a coating film made of a resin with excellent insulating properties such as polyurethane, polyamide-imide, polyimide, polyester, or polyester-imide.

[0037] The first coil conductor 25 is covered by the first base portion 11 of the base body 10. In one embodiment, the first coil conductor 25 is covered by the first base portion 11 such that the first coil surface 25a1 of the first circumferential portion 25a is exposed from the first surface 11a1 of the main body portion 11a. The second coil conductor 35 is covered by the second base portion 12 of the base body 10. The dimensions of the first base portion 11 in the L-axis direction and the W-axis direction are smaller than the dimensions of the second base portion 12 in the L-axis direction and the W-axis direction.

[0038] In the illustrated embodiment, the second base portion 12 has a recess that extends inward from the upper surface of the base 10 towards the interior of the base 10, and the first base portion 11 is housed in this recess. Therefore, the upper surface 10a of the base 10 is defined by the upper surface of the first base portion 11 and the upper surface of the second base portion 12.

[0039] The first base portion 11 will be further described with reference to Figure 4. As shown in Figure 4, the first base portion 11 has a main body portion 11a and a protruding portion 11b. The main body portion 11a covers the first coil conductor 25 such that the first coil surface 25a1 of the first circumferential portion 25a is exposed from the first surface 11a1. The protruding portion 11b protrudes from the first surface 11a1 of the main body portion 11a by a distance D1 in a first direction. In the illustrated embodiment, the protruding portion 11b has a circular shape when viewed from a direction along the coil axis Ax1. The shape of the protruding portion 11b when viewed from a direction along the coil axis Ax1 is not limited to a circular shape, but can be elliptical, oblong, or other shapes.

[0040] Next, an example of a method for manufacturing the magnetically coupled coil component 1 will be described following the flowchart in Figure 5. First, in step S1, the first coil conductor 25 is prepared. As described above, the first coil conductor 25 has a first circumferential portion 25a extending in the circumferential direction around the coil axis Ax1, a first lead portion 25b extending from one end of the first circumferential portion 25a in a direction parallel to the coil axis, and a second lead portion 25c extending from the other end of the first circumferential portion 25a in a direction parallel to the coil axis. The first coil conductor 25 can be made from a strip or wire made of conductive material using a commercially available spindle winding machine, a commercially available flyer winding machine, or any other known winding machine. The method for making the first coil conductor 25 is obvious to those skilled in the art, so a detailed explanation will be omitted.

[0041] Next, in step S2, primary molding is performed to form the first base portion 11. The first base portion 11 is formed, for example, by insert molding. When the first base portion 11 is formed by insert molding, as shown in Figure 6a, a first mold 50 provided with a cavity 51 is prepared, and the first coil conductor 25 prepared in step S1 is set in this cavity 51. Next, as shown in Figure 6b, a mixed composition containing a magnetic material and a resin is filled into the cavity 51. The mixed composition filled into the cavity 51 is, for example, a resin composition containing magnetic powder of a soft magnetic metal and a resin. The composition filled into this cavity 51 is pressed with a punch, and the mixed composition in the cavity 51 is heated at a molding temperature above the curing temperature of the resin contained in the mixed composition in the cavity 51, thereby forming the first base portion 11 with the first coil conductor 25 embedded inside. The first base portion 11 is removed from the first mold 50 for subsequent processes.

[0042] As described above, the first base portion 11 formed in this manner has a main body portion 11a that covers the first coil conductor 25 and a protruding portion 11b that protrudes from the main body portion 11a toward the first direction. Since the cavity 51 of the first mold 50 used in step S2 is formed to be slightly larger than the first coil conductor 25, the first coil conductor 25 can be accurately positioned within the first base portion 11.

[0043] Next, in step S3, the second coil conductor 35 is prepared. As described above, the second coil conductor 35 has a second circumferential portion 35a extending in the circumferential direction around the coil axis, a third lead portion 35b extending from one end of the second circumferential portion 35a in a direction parallel to the coil axis, and a fourth lead portion 35c extending from the other end of the second circumferential portion 35a in a direction parallel to the coil axis. The second coil conductor 35 can be made using a known winding machine, similar to the first coil conductor 25.

[0044] Next, in step S4, secondary molding is performed to form the second base portion 12. In secondary molding, a second mold (not shown) different from the first mold 50 used in primary molding is prepared. A cavity is formed in the second mold. In step S4, first, the first base portion 11 and the second coil conductor 35 are placed in this cavity. For example, the first base portion 11 can be placed in the cavity, and the second coil conductor 35 can be assembled to the first base portion 11 in this cavity. Alternatively, an assembly can be made by assembling the second coil conductor 35 to the first base portion 11, and this assembly can be placed in the cavity of the second mold. The second coil conductor 35 is assembled to the first base portion 11 such that the second coil surface 35a1 is in direct contact with the protrusion 11b of the first base portion 11. Furthermore, the second coil conductor 35 is assembled to the first base portion 11 such that its coil axis is parallel to the coil axis of the first coil conductor 25, which is embedded in the first base portion 11.

[0045] In step S4, a mixed composition containing magnetic material and resin is then filled into the cavity of the second mold, where the assembly of the first base part 11 and the second coil conductor 35 is installed. The mixed composition filled into the cavity of the second mold in secondary molding may be the same as or different from the mixed composition filled into the cavity 51 of the first mold 50 in primary molding. Next, the composition filled into the cavity of the second mold is pressed together with the assembly of the first base part 11 and the second coil conductor 35 using a punch. Next, the composition in the cavity is heated at a molding temperature above the curing temperature of the resin contained in the composition in the cavity, thereby forming a composite molded body in which the first base part 11 and the second base part 12 are combined. If the magnetic material contains epoxy resin, the molding temperature can be set to approximately 150°C. In this way, a composite molded body in which the first base part 11 and the second base part 12 are combined is obtained in step S4.

[0046] Next, the composite molded body formed as described above is removed from the second mold, and one side of the composite molded body removed from the second mold is ground with a cutting blade or laser to expose the end faces of the first pull-out portion 25b, the second pull-out portion 25c, the third pull-out portion 35b, and the fourth pull-out portion 35c. This grinding yields a base body 10 having the first base body portion 11 and the second base body portion 12.

[0047] Next, a conductive paste is applied to cover the exposed surfaces of the first, second, third, and fourth lead portions 25b, 25c, 35b, and 4th lead portions 35c, which are exposed from one surface (upper surface 10a) of the substrate 10, thereby forming the first external electrode 21, second external electrode 22, third external electrode 23, and fourth external electrode 24. This conductive paste contains a conductive material with excellent conductivity, such as Ag, Pd, Cu, Al, Ni, or alloys thereof. A plating layer may be formed on the surface of the first external electrode 21 and the second external electrode 22. There may be two or more plating layers. The two plating layers may include a Ni plating layer and a Sn plating layer provided outside the Ni plating layer.

[0048] As described above, the magnetically coupled coil component 1 is manufactured. According to the above manufacturing method, the first base portion 11 is formed to have an outer shape corresponding to the shape of the cavity 51, so the first base portion 11 can be manufactured with high dimensional accuracy. Furthermore, since the first coil conductor 25 is exposed from the first surface 11a1 of the first base portion 11, and the second coil conductor 35 is assembled so that the second coil surface 35a1 is in direct contact with the protrusion 11b, the distance between the first coil conductor 25 and the second coil conductor 35 can be made equal to the dimension D1 of the protrusion 11b in the axial direction along the coil axis Ax1. Therefore, in the magnetically coupled coil component 1 manufactured as described above, high dimensional accuracy can be obtained regarding the distance between the first coil conductor 25 and the second coil conductor 35.

[0049] Furthermore, according to the above manufacturing method, the first base portion 11 is manufactured using a first mold 50 having a cavity 51 that is slightly larger than the first coil conductor 25, so that the displacement of the first coil conductor 25 from a predetermined installation position within the first base portion 11 can be reduced.

[0050] As described above, according to the above manufacturing method, a magnetically coupled coil component 1 having high dimensional accuracy in the spacing between the first coil conductor 25 and the second coil conductor 35 within the base body 10 can be manufactured.

[0051] Some of the steps included in the manufacturing method described herein may be omitted as appropriate. In the manufacturing method of the magnetically coupled coil component 1, steps not explicitly described herein may be performed as necessary. Some of the steps included in the above manufacturing method of the magnetically coupled coil component 1 may be performed in any order, as long as this does not depart from the spirit of the present invention. Some of the steps included in the above manufacturing method of the magnetically coupled coil component 1 may be performed simultaneously or in parallel, if possible.

[0052] Furthermore, the processes in each of the above steps can be modified as appropriate. For example, in step S4, instead of assembling the second coil conductor 35 to the first base part 11 with the second coil conductor 35 exposed, the second coil conductor 35 may be embedded in the second base part 12, as shown in Figure 7, and then the second base part 12 with the second coil conductor 35 embedded in it may be assembled to the first base part 11. In this case, the second base part 12 with the second coil conductor 35 embedded in it can be manufactured, for example, by insert molding. The second base part 12 covers the second coil conductor 35 such that the second coil surface 35a1 of the second circumferential part 35a is exposed from the second surface 12a1, which is the end face in the second direction. Therefore, the second base portion 12 can be assembled to the first base portion 11 such that the second coil surface 35a1 of the second circumferential portion 35a exposed from the second surface 12a1 is in contact with the protruding portion 11b of the first base portion 11.

[0053] As shown in Figure 8, the protruding portion 11b of the first base portion 11 may be provided with a groove 11b1 that is recessed toward the inside of the first base portion 11, and the second base portion 12 may be provided with a projection 12b that protrudes toward the second direction from the second surface 12a1. The groove 11b1 may have a shape complementary to the projection 12b, for example, and may be configured to accommodate the projection 12b when the second base portion 12 is assembled to the first base portion 11. By providing the groove 11b1 and the projection 12b in appropriate positions, the second base portion 12 can be accurately positioned relative to the first base portion 11 when the second base portion 12 is assembled to the first base portion 11.

[0054] The arrangement of the projection 12b and the groove 11b1 that accommodates the projection 12b shown in Figure 8 can be changed as appropriate. For example, the projection 12b may be provided on the first base portion 11, and the groove 11b1 that receives the projection 12b may be provided on the second base portion 12. In this case, the projection 12b may be formed on the end face of the protruding portion 11b of the first base portion 11 in a first direction, so as to protrude from the end face in a first direction, and the groove 11b1 may be formed on the second surface 12a1 of the second base portion 12 so as to receive the projection 12b formed on the protruding portion 11b.

[0055] Next, a modified example of the first base portion 11 will be described with reference to Figure 9. Figure 9 is a schematic diagram showing a modified example of the first base portion 11. In the first base portion 11 shown in Figure 9, a plurality of protrusions 11b are provided on the first surface 11a1 of the main body portion 11a. In one embodiment of the present invention, the dimensions of each of the plurality of protrusions 11b in the axial direction along the coil axis Ax1 are equal to each other. The second coil conductor 35 is assembled to the first base portion 11 such that the second coil surface 35a1 of the second coil conductor 35 is in contact with each of the plurality of protrusions 11b.

[0056] In Figure 9, each of the multiple protrusions 11b has a circular shape when viewed from the axial direction along the coil axis Ax1. Some of the multiple protrusions 11b may have the same shape as the other protrusions 11b, or they may have different shapes. Also, the radial dimensions of the multiple protrusions 11b may differ from each other. In Figure 9, four protrusions 11b are formed on the first base portion 11, but the number of protrusions 11b formed on the first base portion 11 is not limited to four. The number of protrusions 11b formed on the first base portion 11 may be three or less, or five or more.

[0057] The dimensions, materials, and arrangements of each component described in the various embodiments described above are not limited to those explicitly described in each embodiment, and each component can be modified to have any dimensions, materials, and arrangements that fall within the scope of the present invention.

[0058] Components not explicitly described herein may be added to each of the embodiments described above, and some of the components described in each embodiment may be omitted.

[0059] In this specification, notations such as "Part 1," "Part 2," and "Part 3" are used to identify components and do not necessarily limit their number, order, or content. Furthermore, the numbers used to identify components are used on a context-by-context basis, and a number used in one context does not necessarily indicate the same component in another context. Moreover, this does not prevent a component identified by one number from also performing the function of a component identified by another number.

[0060] This specification also discloses the following technologies: [Note 1] A first coil conductor (25) having a first circumferential portion (25a) extending in the circumferential direction around the coil axis (Ax1), A first base portion (11) having a main body portion (11a) that covers the first coil conductor and has a first surface (11a1) which is an end face in a first direction along the coil axis, and at least one protruding portion (11b) that protrudes from the first surface of the main body portion, The second coil conductor (35) has a second circumferential portion (35a) extending in the circumferential direction around the coil shaft, and is arranged such that the second circumferential portion contacts the at least one protruding portion. The second base portion (12) covers the second coil conductor, A first external electrode (21) connected to one end of the first coil conductor, A second external electrode (22) is connected to the other end of the first coil conductor, A third external electrode (23) is connected to one end of the second coil conductor, A fourth external electrode (24) is connected to the other end of the second coil conductor, A magnetically coupled coil component (1) having the following features. [Note 2] The distance between the first coil conductor and the second coil conductor in the first direction is equal to the dimension (D1) of the protrusion in a uniaxial direction along the coil axis. Magnetic coupling coil component as described in Appendix 1. [Note 3] In the radial direction centered on the coil axis, the outer diameter of the protruding portion is larger than the inner diameter (D4) of the second circumferential portion. Magnetic coupling coil components as described in Appendix 1 or Appendix 2. [Note 4] In the radial direction centered on the coil axis, the outer diameter of the protruding portion is smaller than the outer diameter (D5) of the second circumferential portion. A magnetically coupled coil component as described in any one of the items from Appendix 1 to Appendix 3. [Note 5] The main body covers the first coil conductor such that the first coil surface (25a1), which is the end face of the first circumferential portion in the first direction, is exposed from the first surface. A magnetically coupled coil component as described in any one of the items from Appendix 1 to Appendix 4. [Note 6] The second coil conductor is arranged such that the second coil surface (35a1), which is the end face of the second circumferential portion in the second direction opposite to the first direction, is in contact with the at least one protrusion. A magnetically coupled coil component as described in any one of the items from Appendix 1 to Appendix 5. [Note 7] The main body and the protruding part have a one-piece structure. A magnetically coupled coil component as described in any one of the items from Appendix 1 to Appendix 6. [Note 8] The at least one projection includes a plurality of projections, The second coil conductor is arranged so as to be in contact with each of the plurality of protrusions. A magnetically coupled coil component as described in any one of the items from Appendix 1 to Appendix 7. [Note 9] The dimensions of each of the plurality of protrusions in the direction along the coil axis are equal to each other. Magnetic coupling coil component as described in Appendix 8. [Note 10] The second base portion has a second surface (12a1) which is an end face in a second direction opposite to the first direction, and at least one projection (12b) protruding from the second surface. The at least one projection of the first base portion has a groove (11b1) for receiving the at least one projection. A magnetically coupled coil component as described in any one of the items from Appendix 1 to Appendix 9. [Note 11] The aforementioned protruding portion has at least one projection that protrudes toward the first direction from the end face in the first direction, The second base portion has a groove for receiving at least one projection, A magnetically coupled coil component as described in any one of the items from Appendix 1 to Appendix 10. [Note 12] Step (S1) of preparing a first coil conductor having a first circumferential portion extending in the circumferential direction around the first coil axis, Step (S2) of filling a first mold (50) on which the first coil conductor is installed with a first magnetic material to form a first base body having a main body having a first surface that covers the first coil conductor and is an end face in a first direction along the first coil axis, and at least one protruding portion that protrudes from the first surface, Step (S3) of preparing a second coil conductor having a second circumferential portion extending in the circumferential direction around the second coil axis, The process of assembling the second coil conductor to the first base portion such that the second circumferential portion contacts the protruding portion of the first base portion, A step of providing a first external electrode so as to be connected to one end of the first coil conductor, A step of providing a second external electrode so as to be connected to the other end of the first coil conductor, A step of providing a third external electrode so as to be connected to one end of the second coil conductor, A step of providing a fourth external electrode so as to be connected to the other end of the second coil conductor, A method for manufacturing a magnetically coupled coil component. [Explanation of Symbols]

[0061] 1. Magnetically coupled coil component 10 Base 11. First base section 11a Main body 11b Projection 12 Second base section 21 1st external electrode 22 2nd external electrode 23 Third external electrode 24 4th external electrode 25 First coil conductor 25a First lap section 35. Second coil conductor 35a Second lap section

Claims

1. A first coil conductor having a first circumferential portion extending in the circumferential direction around the coil axis, A first base portion having a main body portion that covers the first coil conductor and has a first surface which is the end face in a first direction along the coil axis, and at least one protruding portion that protrudes from the first surface of the main body portion, A second coil conductor having a second circumferential portion extending in the circumferential direction around the coil shaft, wherein the second circumferential portion is arranged to be in contact with at least one protruding portion, The second base portion covers the second coil conductor, A first external electrode connected to one end of the first coil conductor, A second external electrode connected to the other end of the first coil conductor, A third external electrode connected to one end of the second coil conductor, A fourth external electrode connected to the other end of the second coil conductor, A magnetically coupled coil component equipped with the following features.

2. The distance between the first coil conductor and the second coil conductor in the first direction is equal to the dimension of the protrusion in a uniaxial direction along the coil axis. The magnetically coupled coil component according to claim 1.

3. In the radial direction centered on the coil axis, the outer diameter of the protruding portion is larger than the inner diameter of the second circumferential portion. A magnetically coupled coil component according to claim 1 or 2.

4. In the radial direction centered on the coil axis, the outer diameter of the protruding portion is smaller than the outer diameter of the second circumferential portion. A magnetically coupled coil component according to claim 1 or 2.

5. The main body covers the first coil conductor such that the first coil surface, which is the end face of the first circumferential portion in the first direction, is exposed from the first surface. A magnetically coupled coil component according to claim 1 or 2.

6. The second coil conductor is arranged such that the second coil surface, which is the end face of the second circumferential portion in a second direction opposite to the first direction, is in contact with the at least one protrusion. A magnetically coupled coil component according to claim 1 or 2.

7. The main body and the protruding part have a one-piece structure. A magnetically coupled coil component according to claim 1 or 2.

8. The at least one projection includes a plurality of projections, The second coil conductor is arranged so as to be in contact with each of the plurality of protrusions. A magnetically coupled coil component according to claim 1 or 2.

9. The dimensions of each of the plurality of protrusions in the direction along the coil axis are equal to each other. The magnetically coupled coil component according to claim 8.

10. The second base portion has a second surface which is an end face in a second direction opposite to the first direction, and at least one projection protruding from the second surface. The first base portion has at least one projection having a groove for receiving the at least one projection. The magnetic coupling side coil component according to claim 1 or 2.

11. The aforementioned protruding portion has at least one projection that protrudes toward the first direction from the end face in the first direction, The second base portion has a groove for receiving at least one projection, The magnetic coupling side coil component according to claim 1 or 2.

12. A step of preparing a first coil conductor having a first circumferential portion extending in the circumferential direction around a first coil shaft, A step of filling a first mold in which the first coil conductor is installed with a first magnetic material to form a first base body having a main body that covers the first coil conductor and has a first surface which is an end face in a first direction along the first coil axis, and at least one protruding portion that protrudes from the first surface, A step of preparing a second coil conductor having a second circumferential portion extending in the circumferential direction around the second coil axis, The process involves assembling the second coil conductor to the first base portion such that the second circumferential portion contacts the protruding portion of the first base portion, A step of providing a first external electrode so as to be connected to one end of the first coil conductor, A step of providing a second external electrode so as to be connected to the other end of the first coil conductor, A step of providing a third external electrode so as to be connected to one end of the second coil conductor, A step of providing a fourth external electrode so as to be connected to the other end of the second coil conductor, A method for manufacturing a magnetically coupled coil component.

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