Coil component, coil device, and coil component molding method

Abstract

[Problem] To provide: a coil component, in which the axial direction length including a gap and a coupling part of two coil elements is shortened for size reduction, and deterioration in characteristics and the risk of heat generation that could occur when the leakage magnetic flux comes into contact with a twisted portion can be reduced; a coil device; and a method for producing the coil component. [Solution] The present invention comprises: a first coil element 111 and a second coil element 112 that are formed from a coil winding body which is obtained by rectangularly stacking one rectangular wire 101 in an edge-wise manner, which is divided into two at a predetermined position and folded back, and in which the opposing side surfaces of the coil winding body are disposed so as to be parallel and in close contact with each other; and a coupling part 113 that couples the coil elements 111 and 112. The coupling part 113 is provided along upper surfaces of the coil elements 111, 112 so as to straddle the two coil elements 111, 112. The coupling part 113 includes, at one portion thereof, a twisted section 123D where the rectangular wire 101 is twisted 180°.

Description

[Technical Field]

[0001] The present invention relates to a coil component used as a reactor or the like and a molding method for the coil component, and more particularly to a coil component consisting of two adjacently arranged rectangular cylindrical laminated coils formed from a single rectangular wire, a coil device, and a molding method for the coil component. [Background technology]

[0002] A coil component such as a reactor can generate inductance by having a configuration in which a winding coil is wound around a magnetic core. Various types of reactors are known depending on their intended use, from large-capacity reactors for power transmission systems to components for communication devices. These reactors are housed in a metal case or the like together with other insulating members.

[0003] Incidentally, a reactor used in an in-vehicle boost circuit is known that has two stacked coil elements formed in parallel and connected so that the currents flowing through both coil elements are in opposite directions, so that a high inductance value is obtained when a high current flows through it (see, for example, Patent Document 1 below).

[0004] In Patent Document 1, a first coil element and a second coil element are formed in parallel at opposing positions of a magnetic core that forms a closed loop, and the first and second coil elements are formed by edgewise winding a rectangular wire while forming a bent portion. The connecting portion of the rectangular wire is twisted 180 degrees while being passed between these two coil elements. In addition, there is known a prior art similar to that of Patent Document 1 below, which differs from Patent Document 1 below in that the coil elements are angular and that the connecting portion connecting the two coil elements is located on the front side of the horizontal sides of the two coil elements (see Patent Document 2 below). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 10-172852 [Patent Document 2] JP 2019-153722 A Summary of the Invention [Problem to be solved by the invention]

[0006] In the device disclosed in Patent Document 1, the flat wire at the connecting section is inserted between the opposing sides of the two coil elements and passed from one coil element to the other, so the two coils cannot be placed close together, and the spacing between the coil elements inevitably becomes large, which goes against the demand for compact devices. Furthermore, in a magnetically coupled reactor, the twisted portion of the connecting portion is located in the path of leakage magnetic flux, which causes a problem of heat generation. In the case of Patent Document 2, the spacing between the two coil elements can be improved compared to that of Patent Document 1, which is preferable as it alleviates the problem of heat generation due to the twisted part being outside the path of leakage magnetic flux, but there is a demand for further compactness in the axial length including the connecting part of the coil elements.

[0007] The present invention has been made in consideration of the above circumstances, and aims to provide a coil component, a coil device, and a method for molding a coil component that can reduce the axial length, including the spacing and connecting parts, of two coil elements to make them more compact, and that can reduce the risk of heat generation due to leakage magnetic flux hitting the twisted parts. [Means for solving the problem]

[0008] In order to solve the above problems, a coil component, a coil device, and a method for forming a coil component according to the present invention have the following features. That is, the coil component according to the present invention is A coil winding body formed by edgewise winding a single rectangular wire material and laminating it into a rectangular shape is divided into two at a predetermined position and folded back, and the coil winding body comprises a first coil element and a second coil element arranged so that the opposing side surfaces are parallel to each other, and a connecting portion connecting these two coil elements; When the sides of the rectangular portions constituting the end faces of the coil elements at the end face side relating to the connection of the first coil element and the second coil element that are close to each other and the sides that are parallel to these sides are referred to as first sides, the connecting portion has the connecting portion connects a coil element winding end portion of one of the two coil elements, which is located near an end portion on one side of either of the first sides or on an extension of the first side, to a coil element winding start portion of the other of the two coil elements, which is located near an end portion on one side of either of the first sides or on an extension of the first side, The connecting portion is The flat wire from the coil element winding end portion is provided with a first flatwise bending portion that is bent at a right angle in a flatwise bending manner from the end face side related to the connection to one coil element side of a coil element surface that is parallel to a plane that includes both the arrangement direction of the two coil elements and the axial direction of the two coil elements, and a first connecting portion that is continuous with this first flatwise bending portion and extends in the axial direction of the coil elements along one side of the coil element surface; A second flatwise bent portion is provided in which the flat wire from the coil element winding start portion is bent at a right angle in a flatwise manner from the end face side related to the connection to the other coil element side of the coil element surface, and a second connection portion is provided next to this second flatwise bent portion and extends in the axial direction of the coil element along the other side of the coil element surface; an intermediate connection portion made of the flat wire material arranged along the coil element surface, connecting the end of the flat wire material extending in the first connection portion and the end of the flat wire material extending in the second connection portion; Thus, the hole is formed in a U-shape, The connecting portion is a portion disposed along the surface of the coil element. The flat wire is characterized in that it is configured to have a twisted portion in which the flat wire is twisted by 180 degrees. do.

[0009] In addition, when the first side of the first coil element and the second coil element located on the inside is referred to as an inner first side, and the first side of the connecting portion located on the outside is referred to as an outer first side, the connecting portion is located near the end of the one side of the inner first side of one of the two coil elements or on an extension of the inner first side. The aforementioned Coil element winding start and The aforementioned It is preferable that one of the coil element winding end portions is connected to the other of the coil element winding start portion and the coil element winding end portion, which is located near the end of one side of the outer first edge of the other of the two coil elements or on an extension of the outer first edge.

[0010] In this case, the connecting portion is a connecting portion between the first coil element and the second coil element. the coil element surface In the coil element winding start portion and the coil element winding end portion, The two aforementioned It is preferable that the coil element has two longitudinal sides of a predetermined length extending in the axial direction of the coil elements via a flatwise bend portion, and one side in the arrangement direction of the coil elements connecting the ends of these two longitudinal sides, and that the twisted portion is provided on the side of the two longitudinal sides extending from the first inner side.

[0011] In addition, in the first coil element and the second coil element, The aforementioned The end of the rectangular wire is Perpendicular to the coil element surface It is preferable that the axial length of the slit is formed so as to extend in the direction perpendicular to the axial direction. It is also preferable that the opposing side surfaces of the first coil element and the second coil element are configured to be in close contact with each other.

[0012] Further, the coil device according to the present invention is The coil component is characterized by comprising any one of the coil components described above and a magnetic core portion in which legs are inserted into the hollow portion of the coil component to form a closed magnetic circuit as a whole.

[0013] Further, a method for forming a coil component according to the present invention includes the steps of: A method for forming a coil component using a single rectangular wire material, both ends of which serve as connection terminals, and including a first coil element and a second coil element formed in parallel to each other in a rectangular cylindrical shape by edgewise winding and laminating the portions near both ends, and arranged so that one opposing side surface is parallel to each other, and a connecting portion connecting these two coil elements, The sides constituting the rectangular cylindrical shape are defined as horizontal sides in a direction parallel to the parallel direction connecting the centers of the first coil element and the second coil element when the coil component is molded, and ApplicableWhen referring to the vertical side in the direction perpendicular to the parallel direction, a first coil element forming step of winding and stacking the flat wire material edgewise around the vertical side and the horizontal side from the vicinity of an end of the first coil element of the flat wire material to form the first coil element into a rectangular tube shape; The flat wire is wound from the winding end of the first coil element so as to extend the vertical side. The aforementioned The vertical side extensions of the first coil element are formed by protruding in the outer diameter direction of the rectangular cylindrical shape, and the vertical side extensions are wound edgewise to form the second coil element. For those a connecting portion forming step of bending the first coil element by 90 degrees toward the first coil element so as to form a connecting portion horizontal side parallel to the horizontal side, and then bending the connecting portion horizontal side by 90 degrees toward the second coil element by edgewise winding, thereby forming a vertical side extension of the second coil element parallel to the vertical side extension of the first coil element and continuous with the winding start end of the second coil element; a second coil element forming step of winding and stacking the flat wire material edgewise around the vertical side and the horizontal side in the same direction as the winding direction of the first coil element up to the vicinity of the other end of the flat wire material at a forming position of the second coil element to form the second coil element into a rectangular tube shape, Next, at the position of the connecting portion, the vertical side extension portion of the first coil element is twisted by 180 degrees. By forming a twisted part After performing a coil element dividing step of folding the first coil element and the second coil element in half along a direction perpendicular to the parallel direction, The vertical side extension of the first coil element and the vertical side extension of the second coil element are Among the side surfaces, toward a coil element surface parallel to a plane including both the arrangement direction of the two coil elements and the axial direction of the two coil elements, Flatwise bending at 90 degrees and the twisted portion The connecting portion Coil element surface The method is characterized in that a connecting portion bending step is carried out to align the connecting portion with the connecting portion.

[0014] Here, the above-mentioned "edgewise winding" refers to a winding method in which one of the short side surfaces of the rectangular cross section of the flat wire is used as the inner diameter surface and wound vertically to form a plate, and the above-mentioned "flatwise bending" refers to a bending method in which one of the long side surfaces of the rectangular cross section of the flat wire is used as the inner diameter surface and the flat wire is bent toward the long side. [Effects of the Invention]

[0015] According to the coil component, coil device, and coil component molding method of the present invention, the connecting portion connecting two coil elements is arranged along the upper surfaces of the two coil elements at a predetermined distance, leaving no room for it to get between the two coil elements. In particular, when one long coil element is bent in two along the way to form two coil elements, a twisted portion is formed at the connecting portion between the two coil elements. However, in the present invention, the twisted portion of the connecting portion is arranged along the upper surfaces of the coil elements at a predetermined distance, making it possible to minimize the distance between the two coil elements and eliminate any protruding portion of the connecting portion in the longitudinal direction (axial direction) of the two coil elements, thereby facilitating compactness in the longitudinal direction.

[0016] Furthermore, if leakage magnetic flux continues to hit the twisted portion of the connecting part, heat generation is unavoidable. However, according to the coil component, coil device, and coil component molding method of the present invention, the twisted portion of the connecting part is not positioned on the front side between the two coil elements, so there is little risk of leakage magnetic flux hitting the twisted portion, and heat generation can be significantly suppressed, particularly in magnetically coupled reactors. Furthermore, in the coil device of the present invention, the twisted portion of the connecting portion is not located between the coil element and the inner wall surface of the core, so there is no risk of wasted space being generated, the core shape can be made smaller, and the device can be made more compact. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 1 is a perspective view of a coil component according to an embodiment of the present invention. [Figure 2]2 is a plan view showing the coil device according to the embodiment of FIG. 1 as viewed from above. FIG. [Figure 3] FIG. 2 is a front view of the coil component according to the embodiment of FIG. [Figure 4] 2 is a perspective view showing a main body of a coil device equipped with the coil component according to the embodiment of FIG. 1. FIG. [Figure 5] 5 is a perspective view showing a main body of a coil device according to a modified example of the embodiment shown in FIG. 4. FIG. [Figure 6] 2 is a perspective view showing a method of forming the coil component according to the embodiment of FIG. 1 (manufacturing step 1). FIG. [Figure 7] 2 is a perspective view showing a method for forming the coil component according to the embodiment of FIG. 1 (manufacturing step 2). FIG. [Figure 8] 1. FIG. 4 is a perspective view showing a method for forming the coil component according to the embodiment of FIG. 1 (manufacturing step 3). DETAILED DESCRIPTION OF THE INVENTION

[0018] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A coil component according to an embodiment of the present invention will now be described with reference to the drawings. The coil component according to the present embodiment is applied to, for example, a reactor.

[0019] Reactors are used, for example, as electrical circuit elements in various devices installed in automobiles, and include a magnetic core and a reactor coil wound around this core. Typically, the reactor core is inserted into the reactor coil, and the reactor body can be housed within the case while ensuring insulation between the reactor body and the case.

[0020] <Example> FIG. 1 is a perspective view showing a coil component according to an embodiment of the present invention as viewed from diagonally above the front, FIG. 2 is a plan view showing the coil component according to the embodiment of FIG. 1 as viewed from above, and FIG. 3 is a front view showing the coil component according to the embodiment of FIG. 1 as viewed from the front. As shown in FIG. 1, the coil component 100 of this embodiment is constructed by using a single flat wire 101, wound and laminated in one direction using edgewise winding between one end 101A, which serves as a connection terminal, and the other end 101B, and bending the wound and laminated coil in two at a predetermined position (usually approximately the middle position) to form a first coil element 111 and a second coil element 112 each formed in parallel in a rectangular cylindrical shape, and by providing a connecting portion 113 that connects both coil elements 111 and 112. The rectangular wire material 101 has a rectangular cross section and is made of, for example, a copper wire with an insulating coating applied to the surface thereof. The rectangular cylindrical shape of the coil element is composed of horizontal sides 111G and 112G parallel to the parallel direction connecting the centers of the first coil element 111 and the second coil element 112, and vertical sides 111C and 112C perpendicular to this parallel direction.

[0021] The first coil element 111 and the second coil element 112 are arranged in parallel such that one side surface facing each other is in close contact with each other. In addition, the connecting portion 113 has a first connecting portion (extension of the vertical side of the first coil element) 123A, a second connecting portion (extension of the vertical side of the second coil element) 123B and an intermediate portion (horizontal side of the connecting portion) 123C, and the first connecting portion 123A has a first flatwise bent portion 123A1 and a twisted portion 123D, and the second connecting portion 123B has a second flatwise bent portion 123B1.

[0022] Specifically, the first connection portion 123A includes a first flatwise bent portion 123A1 at a coil element winding end portion 111D of the first coil element 111, where the flat wire material 101 is bent at a right angle in a flatwise manner toward the rear side of Fig. 1, and is arranged so as to have a portion continuing from this first flatwise bent portion 123A1 and extending toward the rear side of Fig. 1 along the upper surface of the first coil element 111. In addition, a twisted portion 123D formed by twisting the flat wire material 101 by 180 degrees is provided at a position along the upper surface of the first connection portion 123A.

[0023] The second connection portion 123B is provided with a second flatwise bending portion 123B1 at the coil element winding start portion 112D of the second coil element 112, where the flat wire material 101 is bent at a right angle toward the back side of FIG. 1 in a flatwise bending manner, and is arranged so as to have a portion following this second flatwise bending portion 123B1 and extending toward the back side of FIG. 1 along the top surface of the second coil element 112.

[0024] The intermediate portion 123C is a portion that connects an end of the first connection portion 123A and an end of the second connection portion 123B, and is arranged to extend in the same direction as the horizontal sides 111G and 112G of the coil elements 111 and 112. The intermediate portion 123C includes edgewise wound portions 123A2 and 123B2 that are bent by 90 degrees by edgewise winding relative to the ends of the respective connection portions 123A and 123B, and is connected to the respective connection portions 123A and 123B by the edgewise wound portions 123A2 and 123B2.

[0025] In the coil component according to this embodiment, as described above, the connecting portion 113 connecting the first coil element 111 and the second coil element 112 is formed in a roughly U-shape consisting of a first connecting portion 123A, a second connecting portion 123B, and an intermediate portion 123C, and this roughly U-shaped portion is configured to fit along the upper surfaces of the coil elements 111 and 112. Furthermore, the connecting portion 113 is connected to the coil element winding end portion 111D of the first coil element 111 and the coil element winding start portion 112D of the second coil element 112 via flatwise bent portions 123A1 and 123B1 that are bent toward the back side of FIG. 1 , so that no part of the connecting portion 113 protrudes from the front side of the coil elements 111 and 112.

[0026] Therefore, it is possible to easily prevent the problem of the portion connecting the first coil element 111 and the second coil element 112 being twisted and getting stuck between these two coil elements 111, 112, as in the prior art described above. Also, it is possible to facilitate the compactness of the coil elements 111, 112 in the longitudinal direction. This prevents the core from becoming too large. Furthermore, heat is generated when leakage magnetic flux continues to hit the twisted portion of this connecting portion 113, but according to the coil component of this embodiment, the twisted portion 123D of the connecting portion is not positioned in front of the two coil elements 111, 112, so that the leakage magnetic flux can be significantly prevented from hitting the twisted portion 123D, and particularly in a magnetically coupled reactor, heat generation can be significantly reduced.

[0027] In this embodiment, the connecting portion 113 connects the coil element winding end portion 111D located on the inner vertical side 111H of the first coil element 111 to the coil element winding start portion 112D located on the outer vertical side 112I of the second coil element 112, but it may also connect the coil element winding end portion located on the outer vertical side 111I of the first coil element 111 to the coil element winding start portion located on the inner vertical side 112H of the second coil element 112 (the coil winding direction will be opposite to that of the embodiment shown in Figure 1). In this embodiment, one end 101A and the other end 101B are arranged to stand upright in the upward direction in the drawing, and the connecting portion 113 is arranged on the upper surfaces of the coil elements 111 and 112. It is also possible to set the one end 101A and the other end 101B described above to stand upright in the opposite direction (from the bottom surface side in FIG. 1), but in this case, the connecting portion 113 would be provided on the opposite side (the bottom surface side in FIG. 1) of the coil elements 111 and 112. This allows the connecting portion 113 to be stored within the vertical space of the coil elements 111 and 112 (the space created by providing one end 101A and the other end 101B), so that the increase in size of the coil component in the vertical direction (up and down direction) is not an issue.

[0028] When constructing a coil device (reactor) using the coil component 100 shown in FIG. 1, the left and right legs of a pair of U-shaped cores 151 and 152 are inserted into the hollow portions 111E and 112E of the two coil elements 111 and 112, as shown in FIG. 4, and are butted against each other inside these hollow portions 111E and 112E to form a coil device (reactor) 180. By configuring it in this manner, there is no risk of hindering compactness in the longitudinal direction of the coil device (axial direction of the coil elements), as in conventional technology where the twisted portion is located between the coil elements 111, 112 and the inner wall of the U-shaped core 152. Generally, this reactor body 180 is housed in a metal housing or the like via an insulating material (not shown).

[0029] 5 shows a magnetically coupled coil device 280 according to another embodiment of the present invention, which is different from the coil device 180 shown in FIG. 5, one coil component 100 (see FIG. 1) is inserted into each of U-shaped cores 251 and 252, and the legs of these U-shaped cores 251 and 252 are butted against each other. In this case, a large leakage magnetic flux may be generated from gap 270 between cores 251 and 252 in the butt-joint region of the legs of U-shaped cores 251 and 252. However, according to the coil component and coil device of this embodiment, twisted portions 223DA and 223DB of flat wire 101 (see FIG. 1) of connecting portions 213A and B are positioned above the upper surfaces of coil elements 211A and 211B, 212A and 212B. This prevents leakage magnetic flux from hitting twisted portions 223DA and 223DB, thereby suppressing heat generation in these portions.

[0030] Furthermore, when combining cores (for example, combining I-shaped cores to form a magnetic path), the cores are generally connected via a gap formed by an insulator or the like to adjust the inductance characteristics of the product, but magnetic flux leaks radially from the gap between the cores, and in the case of the prior art described above, this leakage flux hits the twisted portion of the flat wire at the connecting portion, generating heat and resulting in loss. Even in such a case, the coil component and coil device of this embodiment can prevent the leakage flux from hitting the twisted portions 223DA and 223DB, thereby suppressing heat generation in these areas.

[0031] 6 to 8 are process diagrams showing a method for molding a coil component according to an embodiment. First, as shown in Figure 6, two coil elements 111 and 112 are wound using one flat wire 101, but one turn between the two coil elements 111 and 112 is made to protrude slightly upward as shown in Figure 6, so that the outer diameter in the upward direction is increased by just this one turn (manufacturing process 1: coil element forming process). The two coil elements 111 and 112 are wound in the same direction.

[0032] Next, as shown in Figure 7, at the position of the connecting portion 113, the flat wire 101 is twisted 180 degrees at a predetermined position in the first connection portion 123A (forming the twisted portion 123D), and the first coil element 111 and the second coil element 112 are folded in half along a direction perpendicular to their parallel direction to form a split (manufacturing process 2: coil element splitting process). That is, from the state shown in Fig. 6, the first coil element 111 and the second coil element 112 are rotated 180 degrees clockwise as viewed from above in the figure around the vertical side 111H including the coil element winding end portion 111D of the first coil element 111, to set them to the state shown in Fig. 7. At this time, a twisted portion 123D is formed at a predetermined position of the first connection portion 123A.

[0033] Next, as shown in Figure 8, the first connection portion 123A and the second connection portion 123B of the connecting portion 113 are bent flatwise 90 degrees toward the back of the drawing at positions (flatwise bend portions 123A1, 123B1) that are spaced apart from the top surfaces of the respective coil elements 111, 112 by a similar predetermined height, so that the entire connecting portion 113 is aligned with the top surfaces of the coil elements 111, 112 (manufacturing process 3: connecting portion bending process). The "predetermined height position" can be any distance as long as the twisted portion 123D is not sandwiched between the coil elements 111 and 112, but is preferably a distance that allows a processing jig or the like to be inserted between the connecting portion 113 and the upper surfaces of the coil elements 111 and 112. In other words, in the coil component of this embodiment, the distance between the connecting portion 113 and the coil elements 111 and 112 can be any distance, and therefore bending and twisting can be easily performed depending on the situation.

[0034] In this way, by carrying out manufacturing steps 1 to 3 in order, coil device 100 in which connecting portion 113 is arranged along the upper surfaces of coil elements 111 and 112 can be easily formed. Furthermore, since it is possible to adjust the length of the intermediate portion 123C extending in the arrangement direction of the two coil elements 111 and 112, it is possible to freely set the interval between the two coil elements 111 and 112. Therefore, as in the above-described embodiment, it is also possible to set the interval between the two coil elements 111 and 112 to 0 and place them closely together.

[0035] The coil components and coil devices of the present invention are not limited to those of the above-described embodiment, and may take various other forms. For example, as described above, the intermediate portion 123C of the connecting portion 113 in the above-described embodiment is located above the coil elements 111 and 112, but it may be located below the coil elements 111 and 112 in FIG. 1.

[0036] Furthermore, in the embodiments shown in Figures 4 and 5, U-shaped cores are used as the cores, but in the coil device of the present invention, cores of various other shapes can be used, and for example, it is of course possible to combine I-shaped cores to form the desired magnetic path. Furthermore, in the above embodiment, a method for forming a coil component is described, but it goes without saying that the method for forming a coil component is not limited to this, and various other forming methods can be adopted.

[0037] Furthermore, in the coil components according to the above embodiments, those applied to an on-vehicle reactor are shown, but the coil components, coil devices, and coil component molding methods according to the present invention are not limited to on-vehicle applications and can be applied to a variety of things, and can also be applied to reactors used in solar power generation panels, for example. [Explanation of symbols]

[0038] 100 Coil parts 101 Flat wire rod 101A, B end 111, 211A, B First coil element 111C, 112C Vertical side 111D Coil element winding end 111E, 112E Hollow part 111G, 112G horizontal side 111H, 112H Inner vertical side 111I, 112I Outer vertical side 112, 212A, B Second coil element 112D Coil element winding start 113, 213A, B connection part 123A First Connection 123A1, 123B1 Flatwise bend section 123A2, 123B2 Edgewise winding section 123B Second connection part 123C middle part 123D, 223DA, 223DB Torsion section 151, 152, 251, 252 U-shaped core 180, 280 Coil device (reactor) 270 Gap

Claims

1. The coil winding body is formed by edgewise winding a single rectangular wire material and laminating it into a rectangular shape, and is divided into two at a predetermined position and folded back, and includes a first coil element and a second coil element arranged so that opposing side surfaces are parallel to each other, and a connecting portion connecting these two coil elements; When the sides of the rectangular portions constituting the end faces of the coil elements at the end face side relating to the connection between the first coil element and the second coil element that are close to each other and the sides that are parallel to these sides are referred to as first sides, the connecting portion has the connecting portion connects a coil element winding end portion of one of the two coil elements, which is located near an end portion on one side of either of the first sides or on an extension of the first side, to a coil element winding start portion of the other of the two coil elements, which is located near an end portion on one side of either of the first sides or on an extension of the first side, The connecting portion is a first flatwise bending portion in which the flat wire from the coil element winding end portion is bent at a right angle in a flatwise bending manner from the end face side related to the connection to one coil element side of a coil element surface parallel to a plane including both the arrangement direction of the two coil elements and the axial direction of the two coil elements; and a first connecting portion extending in the axial direction of the coil elements so as to follow the first flatwise bending portion along one side of the coil element surface. The flat wire from the coil element winding start portion is provided with a second flatwise bent portion that is bent at a right angle in a flatwise manner from the end face side related to the connection to the other coil element side of the coil element surface, and a second connection portion that is continuous with the second flatwise bent portion and extends in the axial direction of the coil element along the other side of the coil element surface; an intermediate connection portion made of the flat wire material and arranged along the coil element surface, connecting the end of the flat wire material extending in the first connection portion and the end of the flat wire material extending in the second connection portion; Thus, the hole is formed in a U-shape, A coil component characterized in that the connecting portion is configured to have a twisted portion in which the flat wire is twisted 180 degrees in a part of the portion arranged along the coil element surface.

2. When the first side of the first coil element and the second coil element located on the inside is referred to as an inner first side, and the first side of the connecting portion located on the outside is referred to as an outer first side, 2. The coil component according to claim 1, wherein the connecting portion connects one of the coil element winding start portion and the coil element winding end portion, which is located near the end portion on one side of the inner first side of one of the two coil elements or on an extension of the inner first side, to the other of the coil element winding start portion and the coil element winding end portion, which is located near the end portion on one side of the outer first side of the other of the two coil elements or on an extension of the outer first side.

3. 3. The coil component according to claim 2, wherein the connecting portion has, on the coil element surfaces of the first coil element and the second coil element, two longitudinal sides of the coil elements having a predetermined length that extend from the coil element winding start portion and the coil element winding end portion in the axial direction of the coil elements via the two flatwise fold portions, and one side in the arrangement direction of the coil elements that connects the ends of these two longitudinal sides, and the twisted portion is provided on one of the two longitudinal sides that extends from the first inner side.

4. A coil component according to any one of claims 1 to 3, characterized in that in the first coil element and the second coil element, the end of the flat wire on the opposite side to the connecting portion is formed so as to extend in a direction perpendicular to the coil element surface.

5. 5. The coil component according to claim 1, wherein opposing side surfaces of the first coil element and the second coil element are configured to be in close contact with each other.

6. A coil device comprising the coil component according to any one of claims 1 to 5, and a magnetic core portion in which legs are inserted into the hollow portion of the coil component to form a closed magnetic circuit as a whole.

7. A method for forming a coil component using a single rectangular wire material, both ends of which serve as connection terminals, and including a first coil element and a second coil element formed side by side in a rectangular cylindrical shape by edgewise winding and stacking the portions near both ends, and arranged so that one opposing side surface is parallel to each other, and a connecting portion connecting these two coil elements, When the sides constituting the rectangular tube shape are referred to as horizontal sides parallel to the parallel direction connecting the centers of the first coil element and the second coil element in a molded state of the coil component, and vertical sides perpendicular to the parallel direction, a first coil element forming step of winding and stacking the flat wire material edgewise around the vertical side and the horizontal side from the vicinity of an end of the first coil element of the flat wire material to form the first coil element into a rectangular tube shape; a connecting portion forming step of extending the flat wire rod from the winding end of the first coil element in the outer diameter direction of the rectangular tube shape so as to extend the vertical side, thereby forming a vertical side extension of the first coil element, further bending the vertical side extension by 90 degrees toward the second coil element by edgewise winding to form a connecting portion horizontal side parallel to the horizontal side, and then bending the connecting portion horizontal side by 90 degrees toward the second coil element by edgewise winding to form a vertical side extension of the second coil element parallel to the vertical side extension of the first coil element and continuous with the winding start end of the second coil element; a second coil element forming step of winding and stacking the flat wire material edgewise around the vertical side and the horizontal side in the same direction as the winding direction of the first coil element up to the vicinity of the other end of the flat wire material at the forming position of the second coil element to form the second coil element into a rectangular tube shape, Next, a coil element dividing step is performed in which the first coil element and the second coil element are folded in half along a direction perpendicular to the parallel direction by twisting the vertical side extension of the first coil element by 180 degrees at the position of the connecting portion to form a twisted portion, and a connecting portion bending step for bending the vertical side extension of the first coil element and the vertical side extension of the second coil element by 90 degrees flatwise toward a coil element surface that is parallel to a plane that includes both the arrangement direction of the two coil elements and the axial direction of the two coil elements among the side surfaces of the first coil element and the second coil element, and aligning the connecting portion including the twisted portion along the coil element surface.

Images