Coil Device

Abstract

To provide a coil device with a small number of components.SOLUTION: A coil device 10 has a bobbin 20 having a winding core part 21 in which a first coil part 41 and a second coil part 42 are arranged, cores 50a, 50b attached to the bobbin 20, and bypass cores 55a, 55b attached to the bobbin 20 to bypass a part of a magnetic flux generated in cores 50a, 50b. On the outer surface of the winding core part 21, core installation parts 31a, 31b are formed having a recess 32 that is open toward the outside in the radial direction of the winding core part 21 and can accommodate the bypass cores 55a, 55b.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a coil device. [Background technology]

[0002] A coil device equipped with a bypass core is known as a coil device used as a leakage transformer (Patent Document 1). The coil device described in Patent Document 1 has, in addition to the bypass core, a first bobbin on which a first coil portion (primary coil) is formed, and a second bobbin on which a second coil portion (secondary coil) is formed. An end face of a first flange portion formed at one axial end of the first bobbin is joined to an end face of a second flange portion formed at one axial end of the second bobbin, thereby enabling the first bobbin and the second bobbin to be combined along their respective axial directions.

[0003] A bypass core can be installed at the position where the first bobbin and the second bobbin are combined. More specifically, a recess capable of accommodating the bypass core is formed in the end face of the first flange, and with the bypass core accommodated in the recess, the end face of the second flange is joined to the end face of the first flange (the opening edge of the recess), thereby making it possible to fix the bypass core at the position where the first bobbin and the second bobbin are combined (i.e., between the first coil portion and the second coil portion).

[0004] However, the coil device described in Patent Document 1 requires two bobbins, a first bobbin and a second bobbin, which not only increases the number of parts but also requires high dimensional accuracy for these bobbins and bypass cores in order to combine these bobbins with precision, so improvements are desired. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Publication No. 59-109121 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a coil device with a reduced number of parts. [Means for solving the problem]

[0007] In order to achieve the above object, a coil device according to the present invention comprises: a bobbin having a winding core on which the first coil portion and the second coil portion are arranged; a main core attached to the bobbin; a bypass core attached to the bobbin for bypassing a portion of the magnetic flux generated in the main core, A core installation portion is formed on the outer peripheral surface of the winding core portion, the core installation portion having a recess that opens outward in the radial direction of the winding core portion and is capable of accommodating the bypass core.

[0008] In the coil device according to the present invention, a core installation section is formed on the outer peripheral surface of the winding core section, the core installation section having a recess that opens radially outward from the winding core section and can accommodate a bypass core. Therefore, the bypass core can be accommodated inside the recess through the opening from the radially outward side of the winding core section, and the bypass core can be stably fixed to the bobbin (core installation section). Therefore, unlike the conventional technology, there is no need to use multiple bobbins to fix the bypass core, which contributes to reducing the number of parts and labor and allows for a more compact coil device. Furthermore, since there is no need to consider combinations with other bobbins, the bobbins and bypass core do not require as high dimensional accuracy as in the conventional technology, which contributes to improving the performance of the coil device. Furthermore, there is no need to require high alignment accuracy when accommodating the bypass core inside the recess, which improves workability.

[0009] Furthermore, by adjusting the size of the bypass core, it is possible to precisely adjust the leakage characteristics between the first coil section and the second coil section. In particular, by adjusting the size of the bypass core so that it is the minimum size necessary to bypass the magnetic flux generated in the main core, it is possible to effectively reduce the size (profile) of the coil device.

[0010] Preferably, the core installation portion has a portion that protrudes radially outward from the winding core portion, and the first coil portion is arranged on one axial side of the winding core portion relative to the core installation portion, and the second coil portion is arranged on the other axial side of the winding core portion relative to the core installation portion. With this configuration, the core installation portion is formed between the first coil portion and the second coil portion, and it becomes possible to arrange a bypass core between the first coil portion and the second coil portion. By arranging the bypass core in this position, it is possible to accurately adjust the leakage characteristics between the first coil portion and the second coil portion.

[0011] Preferably, the core installation portion is formed on a side portion of the outer peripheral surface of the winding core portion along the circumferential direction of the winding core portion, and the inner surface of the recess extends radially outward of the winding core portion. By forming the core installation portion on a side portion of the outer peripheral surface of the winding core portion along the circumferential direction of the winding core portion and installing the bypass core to the side of the outer peripheral surface of the winding core portion, it is possible to reduce the height of the coil device. Furthermore, by forming the recess so that the inner wall surface extends radially outward of the winding core portion, it becomes possible to accommodate the bypass core in the recess by fitting it from the radially outward side of the winding core portion, for example, and this makes it easier to install the bypass core on the bobbin.

[0012] Preferably, the winding core has a through hole formed therein extending along the axial direction of the winding core, the main core has a center leg portion disposed inside the through hole and an outer leg portion disposed outside the winding core, and the bypass core is disposed between the center leg portion and the outer leg. By disposing the bypass core between the center leg portion and the outer leg, it is possible to efficiently guide a portion of the magnetic flux generated in the main core into the bypass core, and it is possible to accurately adjust the leakage characteristics between the first coil portion and the second coil portion.

[0013] Preferably, the bypass core has a columnar shape, and the inner surface of the bypass core is curved along the outer surface of the center leg. With this configuration, the distance between the inner surface of the bypass core and the outer surface of the center leg is approximately constant at the curved portion of the bypass core, which prevents the formation of a localized area with low magnetic resistance between them and prevents abnormal heat generation in the bypass core or the center leg.

[0014] Preferably, the center leg and the outer leg extend along a first axis and are spaced apart at a predetermined interval along a second axis perpendicular to the first axis, and the cross-sectional area of ​​the center leg on one side of the center is larger than the cross-sectional area of ​​the center leg on the other side of the center with respect to a third axis perpendicular to the first and second axes. This configuration results in a relatively larger surface area of ​​the center leg on one side of the center of the center in the third axis direction than on the other side of the center of the center in the third axis direction. Therefore, when the bobbin, main core, etc. are covered with potting resin, the contact area between the potting resin and the center leg can be increased on one side of the center of the center in the third axis direction, allowing heat from the main core to be efficiently dissipated to the outside through this area.

[0015] Preferably, the coil assembly includes a case that houses the bobbin and a potting resin that is filled in the case, and the cross-sectional area of ​​the bottom side of the case relative to the center of the middle leg is larger than the cross-sectional area of ​​the opening side of the case relative to the center of the middle leg. This configuration increases the contact area between the potting resin and the middle leg on the bottom side of the case, allowing efficient dissipation of heat from the main core to the outside through this area. Furthermore, since the bottom of the case functions as a cooling section, this configuration promotes heat dissipation from the middle leg to the bottom of the case, thereby improving the cooling efficiency of the coil assembly.

[0016] Preferably, the coil device has a terminal block formed separately from the bobbin and attached to one end and the other end in the axial direction of the bobbin, the terminal block being located at a position spaced apart laterally from the outer circumferential surface of the winding core. By forming the terminal block separately from the bobbin, it becomes possible to wind the wire around the outer circumferential surface of the winding core with the terminal block removed from the bobbin during manufacturing of the coil device, and this prevents the terminal block from interfering with automatic winding by the automatic winding machine, particularly when winding the wire using an automatic winding machine. Furthermore, by forming (only) the terminal block from a highly heat-resistant resin separately from the bobbin, a heat-resistant coil device can be realized at low cost.

[0017] Furthermore, by positioning the terminal block at a position spaced apart laterally from the outer peripheral surface of the winding core portion, it is possible to reduce the size (length) of the coil device in the axial direction of the winding core portion compared to when the terminal block is formed at the axial end of the winding core portion, thereby enabling the coil device to be made smaller. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 1 is a perspective view of a coil device according to a first embodiment of the present invention. [Figure 2A] FIG. 2A is a perspective view showing the coil device shown in FIG. 1 without the case and potting resin. [Figure 2B]FIG. 2B is a cross-sectional view of the coil device shown in FIG. 2A taken along line IIB-IIB. [Figure 3] FIG. 3 is an exploded perspective view of the coil device shown in FIG. [Figure 4] FIG. 4 is a side view of the center leg portion and the outer leg portion of the core shown in FIG. 3 as viewed from the inside in the Y-axis direction. [Figure 5] FIG. 5 is a perspective view of the bobbin shown in FIG. [Figure 6] FIG. 6 is a perspective view of the terminal and terminal block shown in FIG. [Figure 7] 7 is a perspective view of the bobbin shown in FIG. 5 to which the terminal block, terminals, first coil portion, second coil portion, and bypass core shown in FIG. 3 are attached. [Figure 8] FIG. 8 is a cross-sectional view of the coil device shown in FIG. 2A taken along line VIII-VIII. [Figure 9] FIG. 9 is a perspective view of a coil device according to the second embodiment of the present invention. [Figure 10] FIG. 10 is a perspective view of the coil device shown in FIG. 9 when the first coil portion, the second coil portion, and the bypass core are attached to the bobbin. DETAILED DESCRIPTION OF THE INVENTION

[0019] Hereinafter, the present invention will be described based on the embodiments shown in the drawings.

[0020] First embodiment The coil device 10 according to this embodiment shown in FIG. 1 functions as, for example, a leakage transformer and is used, for example, in an on-board charger for an EV (Electric Vehicle), a PHV (Plug-in Hybrid Vehicle), or a commuter vehicle, a power supply circuit for home or industrial electrical equipment, or a power supply circuit for computer equipment. The detailed configuration of the coil device 10 will be described below. In the following description, the positive Z-axis direction in the drawings will be referred to as the upper side, and the negative Z-axis direction will be referred to as the lower side. Furthermore, the side facing the center of the coil device 10 will be referred to as the inside or inner side, and the side away from the center of the coil device 10 will be referred to as the outside or outer side.

[0021] As shown in Fig. 3, the coil device 10 includes a bobbin 20, a first coil portion 41 and a second coil portion 42, cores (main cores) 50a and 50b, bypass cores 55a and 55b, first terminals 61_1 and 61_2, second terminals 62_1 and 62_2, a terminal block 70, a cover portion 80, and a case 90. The coil device 10 is a horizontal coil device in which the winding axes of the first coil portion 41 and the second coil portion 42 are parallel to the surface of a mounting board (not shown). The mounting board is disposed above the coil device 10 shown in Fig. 1 (on the positive side of the Z axis), and the upper side of the coil device 10 serves as the installation surface (mounting surface) of the coil device relative to the mounting board.

[0022] The case 90 is made of a metal with excellent cooling properties, such as aluminum, and has a case bottom 91 and case side portions 92. The top of the case 90 is open, and the bobbin 20 and the like can be accommodated through an opening formed in the top of the case 90. The case bottom 91 has a generally rectangular shape and forms the bottom surface of the case 90. The case side portions 92 have a generally square cylindrical shape overall and are formed along the outer edge of the case bottom 91.

[0023] More specifically, case side portions 91 extend upward from each of the four sides that form the outer edge of case bottom portion 91. Case 90 is formed by bending a single metal plate or the like, and case side portions 92 have mating surfaces at the bent portions that form joints 93. Note that joints 93 may be liquid-tightly sealed by applying an adhesive or the like to them.

[0024] The storage space formed by the case bottom 91 and the case side 92 can accommodate the bobbin 20 and the like, and can also be filled with potting resin (heat dissipating resin) 100, as shown in Fig. 1. The potting resin 100 is made of silicone resin, urethane resin, epoxy resin, or the like. The potting resin 100 is filled up to the position of the opening of the case 90, and from the top surface of the hardened potting resin 100, part of the bobbin 20, part of the terminals 61_1, etc., or part of the cover part 80 are exposed.

[0025] In this embodiment, heat generated in the bobbin 20 and the like can be dissipated to the outside via the case 90 and the potting resin 100, and the coil device 10 can be cooled efficiently.

[0026] 3, the first coil portion 41 is formed by winding a first wire 41c around the outer peripheral surface of the winding core portion 21 of the bobbin 20. The second coil portion 42 is formed by winding a second wire 42c around the outer peripheral surface of the winding core portion 21 of the bobbin 20. The first wire 41c and the second wire 42c are wound around the outer peripheral surface of the winding core portion 21 using, for example, an automatic winding machine.

[0027] The first coil portion 41 is formed of two layers in a direction (radial direction) perpendicular to its winding axis, and the second coil portion 42 is formed of three layers in a direction (radial direction) perpendicular to its winding axis (see FIG. 2B). The winding axes of the first coil portion 41 and the second coil portion 42 are substantially aligned and correspond to the Y-axis direction.

[0028] The first coil portion 41 is provided on one side in the Y-axis direction of the winding core portion 21 (the positive Y-axis side), and the second coil portion 42 is provided on the other side in the Y-axis direction of the winding core portion 21 (the negative Y-axis side). Either the first coil portion 41 or the second coil portion 42 constitutes a primary coil, and the other of the first coil portion 41 and the second coil portion 42 constitutes a secondary coil. The primary coil and the secondary coil in the winding core portion 21 may be arranged on either one side or the other side in the Y-axis direction of the winding core portion 21.

[0029] The first wire 41c and the second wire 42c are each made of an insulating coated wire, such as a conductor such as a copper wire. The first wire 41c and the second wire 42c may each be made of a solid wire or a twisted wire. The wire diameter (diameter) of the first wire 41c and the second wire 42c is preferably, for example, 1.0 to 3.0 mm. The wire diameters of the first wire 41c and the second wire 42c may be the same or different. For example, the wire diameter of the first wire 41c or the second wire 42c through which a larger current flows may be made thicker than the wire diameter of the other wire.

[0030] A lead portion 41a is formed at one end of the first coil portion 41, and a lead portion 41b is formed at the other end of the first coil portion 41. For example, the lead portion 41a is drawn out from the first layer of the first coil portion 41, and the lead portion 41b is drawn out from the second layer of the first coil portion 41.

[0031] Furthermore, a lead portion 42a is formed at one end of the second coil portion 42, and a lead portion 42b is formed at the other end of the second coil portion 42. For example, the lead portion 42a is drawn out from the first layer of the second coil portion 42, and the lead portion 42b is drawn out from the third layer of the second coil portion 42.

[0032] Core 50a and core 50b are so-called E-shaped cores and are attached to bobbin 20. Cores 50a and 50b may be made of, but are not limited to, metal, ferrite, or other magnetic materials. Core 50a and core 50b have the same shape. Core 50a has a base 51a, a pair of outer legs 52a, and a center leg 53a. Core 50b has a base 51b, a pair of outer legs 52b, and a center leg 53b. The following describes the configuration of core 50a, but the description of core 50a also applies to core 50b. Therefore, unless otherwise necessary, a description of the configuration of core 50b will be omitted.

[0033] The base portion 51a has a predetermined thickness in the Y-axis direction, and has predetermined lengths in each of the X-axis and Z-axis directions, as shown in Fig. 4. In this embodiment, as shown in Fig. 1, the inside of the case 90 is filled with potting resin 100, and therefore a resin layer made of potting resin 100 is formed around the cores 50a and 50b.

[0034] 3, the center leg 53a is disposed between the pair of outer leg portions 52a and is connected to the inner surface of the base portion 51a. The center leg 53a extends a predetermined length along the Y-axis direction from the inner surface of the base portion 51a and is disposed inside a through hole 211 formed in the winding core portion 21 of the bobbin 20. The center leg 53a of the core 50a and the center leg 53b of the core 50b are disposed inside the through hole 211 with their respective tip ends butted against each other. A gap may be formed along the Y-axis direction between the tip end of the center leg 53a and the tip end of the center leg 53b.

[0035] As shown in FIG. 4, the middle leg portion 53a is not formed at the center of the inner surface of the base portion 51a, but is formed at a position displaced upward (one side in the Z-axis direction) from the center C1 of the inner surface of the base portion 51a. The distance between the center C2 of the middle leg portion 53a and the center C1 of the inner surface of the base portion 51a (i.e., the displacement width of the center C2 in the Z-axis direction with respect to the center C1) L1 may be determined based on the length L2 of the base portion 51a along the Z-axis direction. The ratio L1 / L2 of the above L1 and the above L2 is preferably 0 < L1 / L2 < 1 / 4, and more preferably 0 < L1 / L2 < 1 / 8.

[0036] By setting the value of L1 / L2 within the above range, a relatively wide space can be formed below the middle leg portion 53a (between the lower end of the middle leg portion 53a and the lower end of the base portion 51a). Therefore, when the potting resin 100 is filled inside the case 90, the potting resin 100 can be made to flow into the above space, and the potting resin 100 can be efficiently filled below the core 50a.

[0037] The center C2 of the middle leg portion 53a is a position where the length L3 from one end of the middle leg portion 53a in the X-axis direction is equal to the length L4 from the other end of the middle leg portion 53a in the X-axis direction, and the length L5 from one end of the middle leg portion 53a in the Z-axis direction is equal to the length L6 from the other end of the middle leg portion 53a in the Z-axis direction. That is, the length L3 between the center C2 of the middle leg portion 53a and one end of the middle leg portion 53a in the X-axis direction is equal to the length L4 between the center C2 of the middle leg portion 53a and the other end of the middle leg portion 53a in the X-axis direction, and the length L5 between the center C2 of the middle leg portion 53a and one end of the middle leg portion 53a in the Z-axis direction is equal to the length L6 between the center C2 of the middle leg portion 53a and the other end of the middle leg portion 53a in the Z-axis direction.

[0038] As described above, since the center C2 of the middle leg portion 53a is displaced upward with respect to the center C1 of the base portion 51a, the length L7 between the upper end of the middle leg portion 53a and the upper end of the base portion 51a is shorter than the length L8 between the lower end of the middle leg portion 53a and the lower end of the base portion 51a (L7 < L8). By setting L7 < L8 in this way, as described above, it becomes possible to form a relatively wide space that can be used as a flow path for the potting resin 100 below the middle leg portion 53a.

[0039] The cross-sectional shape of the middle leg portion 53a (the cross-sectional shape of a plane parallel to the XZ plane) is not a perfect circle or a perfect ellipse, unlike the middle leg portion of a well-known E-shaped core. It has an asymmetric shape on the upper side and the lower side with respect to a line segment passing through the center C2 of the middle leg portion 53a and parallel to the X axis. Also, the cross-sectional shape of the middle leg portion 53a is different between one side (lower side) in the Z-axis direction from the center C2 of the middle leg portion 53a and the other side (upper side) in the Z-axis direction from the center C2 of the middle leg portion 53a.

[0040] More specifically, the cross-sectional shape of the middle leg portion 53a has a shape that bulges in the X-axis direction as a whole on the lower side than the center C2 of the middle leg portion 53a, compared to the upper side than the center C2 of the middle leg portion 53a. That is, when considering the shape of the middle leg portion 53a on the upper side than the center C2 of the middle leg portion 53a as a reference, a bulging portion (thick portion) that bulges outward in the X-axis direction is provided on the lower side than the center C2 of the middle leg portion 53a.

[0041] The cross-sectional area of the middle leg portion 53a on the lower side than the center C2 is larger than the cross-sectional area of the middle leg portion 53a on the upper side than the center C2. Therefore, the surface area or volume of the middle leg portion 53a on the lower side than the center C2 is larger than the surface area or volume of the middle leg portion 53a on the upper side than the center C2. Also, when looking at the middle leg portion 53a in cross-section, the length of the outer peripheral surface of the middle leg portion 53a on the lower side than the center C2 of the middle leg portion 53 is longer than the length of the outer peripheral surface of the middle leg portion 53a on the upper side than the center C2 of the middle leg portion 53a.

[0042] The ratio S1 / S2 of the cross-sectional area S1 below the center C2 of the middle leg portion 53a to the cross-sectional area S2 above the center C2 of the middle leg portion 53a is preferably 0 < S1 / S2 < 1, and more preferably 0.5 < S1 / S2 < 1.

[0043] By setting the value of S1 / S2 within the above range, when covering the bobbin 20, the core 50a, etc. with the potting resin 100 (FIG. 1), it is possible to increase the contact area between the potting resin 100 and the middle leg portion 53a below the center C2 of the middle leg portion 53a, and through this portion, the heat of the core 50a can be efficiently dissipated to the outside.

[0044] When looking at the cross-sectional shape of the middle leg portion 53a in relation to the case 90 (FIG. 3), the cross-sectional area of the middle leg portion 53a on the bottom surface side of the case 90 (case bottom portion 91 side) relative to the center C2 of the middle leg portion 53a is larger than the cross-sectional area of the middle leg portion 53a on the opening side of the case 90 relative to the center C2 of the middle leg portion 53a. By making the cross-sectional shape of the middle leg portion 53a such a shape in relation to the case 90, it is possible to increase the contact area between the potting resin 100 and the middle leg portion 53a on the bottom surface side of the case 90, and through this portion, the heat of the core 50a can be efficiently dissipated toward the bottom surface of the case 90.

[0045] Also, while the case bottom portion 91 of the case 90 functions as a cooling portion, by making the cross-sectional shape of the middle leg portion 53a the above-described shape, heat dissipation from the middle leg portion 53a to the case bottom portion 91 can be promoted, and the cooling efficiency of the coil device 10 can be increased.

[0046] The maximum value of the width along the X-axis direction of the middle leg portion 53a below the center C2 of the middle leg portion 53a is larger than the maximum value of the width along the X-axis direction of the middle leg portion 53a above the center C2 of the middle leg portion 53a.

[0047] Moreover, above the center C2 of the middle leg 53a, the width of the middle leg 53a along the X-axis direction gradually decreases as it moves upward. On the other hand, below the center C2 of the middle leg 53a, the width of the middle leg 53a along the X-axis direction gradually increases (expands in the X-axis direction) as it moves downward until it reaches a certain position, after which it gradually decreases.

[0048] 3, the pair of outer legs 52a are arranged at a predetermined interval along the X-axis direction and are connected to the inner surface of the base portion 51a. One of the pair of outer legs 52a is arranged at one end of the inner surface of the base portion 51a in the X-axis direction, and the other of the pair of outer legs 52a is arranged at the other end of the inner surface of the base portion 51a in the X-axis direction.

[0049] The pair of outer leg portions 52 a extend a predetermined length from the inner surface of the base portion 51 along the Y-axis direction, and are disposed outside the winding core portion 21 of the bobbin 20 .

[0050] Bypass cores 55a and 55b are cores for bypassing part of the magnetic flux generated in cores 50a and 50b. That is, part of the magnetic flux generated in cores 50a and 50b is guided inside bypass cores 55a and 55b. Examples of materials for bypass cores 55a and 55b include, but are not limited to, magnetic materials such as metal and ferrite.

[0051] The bypass cores 55a and 55b each have the same shape and are formed into a columnar shape (approximately a rectangular parallelepiped). More specifically, the bypass cores 55a and 55b each are formed into a columnar body having a generally C-shape that gently curves inward (toward the bobbin 20). As shown in FIG. 8, the core inner surface (inner surface) 550a of the bypass core 55a curves along the lateral portion of the middle leg outer surface 530a of the middle leg 53a, which is disposed opposite the bypass core 55a. The core inner surface (inner surface) 550b of the bypass core 55b curves along the lateral portion of the middle leg outer surface 530a of the middle leg 53a, which is disposed opposite the bypass core 55a.

[0052] 3, in bypass cores 55a and 55b, the degree of curvature of core inner surfaces 550a and 550b is approximately equal to the degree of curvature of core outer surfaces (outer surfaces) 551a and 551b, respectively. Core side surfaces 552a and 553a face each other along the Y-axis direction and are each formed to be approximately parallel to the XZ plane. The same is true for core side surfaces 552b and 553b. Core upper surface 554a and core lower surface 555a face each other along the Z-axis direction and are each formed to be approximately parallel to the XY plane.

[0053] The bypass core 55a is housed in a recess 32 of a core installation portion 31a of the bobbin 20, which will be described later, and the bypass core 55b is housed in a recess 32 of a core installation portion 31b of the bobbin 20, which will be described later.

[0054] The bobbin 20 is made of a plastic such as PPS, PET, PBT, or LCP, or another insulating material (preferably a heat-resistant material). The bobbin 20 has a winding core 21, flanges 22a and 22b, and terminal block fixing portions 23a and 23b.

[0055] A first wire 41c and a second wire 42c are wound around the outer peripheral surface of the winding core 21 to form a first coil portion 41 and a second coil portion 42. The first coil portion 41 is disposed on one side of the winding core 21 in the Y-axis direction, between the flange 22a and an insulating partition portion 30, a core installation portion 31a, a core installation portion 31b, and a connecting portion 33 (described later). The second coil portion 42 is disposed on the other side of the winding core 21 in the Y-axis direction, between the flange 22b and an insulating partition portion 30, a core installation portion 31a, a core installation portion 31b, and a connecting portion 33 (FIG. 7). Note that the first coil portion 41 and the second coil portion 42 may be disposed on the winding core 21 in advance.

[0056] One end of the first coil portion 41 in the winding axis direction is located adjacent to the flange portion 22a, and the other end of the first coil portion 41 in the winding axis direction is located adjacent to the insulating partition portion 30, the core installation portion 31a, the core installation portion 31b, and the connecting portion 33. One end of the second coil portion 42 in the winding axis direction is located adjacent to the flange portion 22b, and the other end of the second coil portion 42 in the winding axis direction is located adjacent to the insulating partition portion 30, the core installation portion 31a, the core installation portion 31b, and the connecting portion 33.

[0057] The winding core 21 is a cylindrical body having a substantially elliptical shape, and the axial direction of the winding core 21 coincides with the Y-axis direction. A through hole 211 is formed inside the winding core 21, and the center legs 53a and 53b of the cores 50a and 50b can be accommodated inside the through hole 211. As described above, the coil device 10 in this embodiment is a horizontal coil device, and therefore the axial direction of the winding core 21 is substantially parallel to the mounting surface of the coil device 10 or the mounting surface of the mounting board (not shown). This makes it possible to reduce the height of the coil device 10, thereby enabling the coil device 10 to have a low profile.

[0058] As shown in FIG. 8, the cross-sectional shape of the winding core 21 (the cross-sectional shape of a plane parallel to the XZ plane) is substantially elliptical. The cross-sectional shape of the winding core 21 corresponds to the shape of the outer peripheral surface of the center leg 53a, and the side portions of the outer peripheral surface of the winding core 21 are curved along the center leg outer surface 530a of the center leg 53a. The degree of curvature of the long-side surfaces of the winding core 21 (the upper and lower portions of the outer peripheral surface of the winding core 21) is substantially the same as the degree of curvature of the long-side sides of the center leg outer surface 530a, and the degree of curvature of the short-side surfaces of the winding core 21 (the lateral portions of the outer peripheral surface of the winding core 21) is substantially the same as the degree of curvature of the short-side sides of the center leg outer surface 530a. A gap is formed between the inner surface (inner surface) of the winding core 21 and the outer peripheral surface of the center leg 53a, and potting resin 100 (FIG. 1) can be inserted into this gap.

[0059] As shown in FIG. 5 , flange portion 22a is formed at one axial end of winding core portion 21, and flange portion 22b is formed at the other axial end of winding core portion 21. Flange portion 22a and flange portion 22b have the same shape. Flange portion 22a has a flange portion main body 220a that extends circumferentially along the outer circumferential surface of winding core portion 21 at one end of winding core portion 21 in the Y axis direction. Flange portion 22b has a flange portion main body 220b that extends circumferentially along the outer circumferential surface of winding core portion 21 at the other end of winding core portion 21 in the Y axis direction. Flange portion main body 220a is made of a plate having a predetermined thickness in the Y axis direction and protrudes outward in the radial direction of winding core portion 21. Flange portion main body 220b is made of a plate having a predetermined thickness in the Y axis direction and protrudes outward in the radial direction of winding core portion 21.

[0060] A mounting portion 29a is integrally formed at the lower end of the flange body 220a. The mounting portion 29a extends substantially parallel to the XZ plane relative to the flange body 220a, and the bottom surface of the mounting portion 29a is substantially flat. The bobbin 20 is mounted on the case bottom 91 of the case 90 (FIG. 3) via the mounting portion 29a.

[0061] A mounting portion 29b is integrally formed at the lower end of the flange main body 220b. The configuration and function of mounting portion 29b are similar to those of mounting portion 29a, and therefore detailed description thereof will be omitted. The winding core 21 of the bobbin 20 and other components can be supported via mounting portions 29a, 29b, and mounting portion 29c, which will be described later.

[0062] A fixing flange 24a is formed above the flange body 220a. The fixing flange 24a is integrally connected to the upper part of the flange body 220a and extends approximately parallel to the flange body 220a along the XZ plane. In other words, the fixing flange 24a has a shape that extends the flange body 220a upward, and constitutes a part of the flange body 220a. The fixing flange 24a is formed on the upper end of the flange body 220a on the negative X-axis direction side, and protrudes above the terminal block fixing portion 23a.

[0063] The fixing flange 24a has a predetermined thickness in the Y-axis direction and a surface substantially parallel to the XZ plane. The fixing flange 24a also extends to face a surface parallel to the XZ plane of a lateral fixing portion 72a (FIG. 6) of the terminal block 70, which will be described later.

[0064] A fixing flange 24b is formed above the flange body 220b. The configuration and function of the fixing flange 24b are similar to those of the fixing flange 24a, and therefore detailed description thereof will be omitted. The fixing flange 24b extends so as to face a plane parallel to the XZ plane of a lateral fixing portion 72b (FIG. 6) of the terminal block 70, which will be described later.

[0065] At one end of bobbin 20 in the Y axis direction, terminal block fixing portion 23a is formed to which one end of terminal block 70 (FIG. 6) in the Y axis direction is fixed, and at the other end of bobbin 20 in the Y axis direction, terminal block fixing portion 23b is formed to which the other end of terminal block 70 in the Y axis direction is fixed. Terminal block fixing portions 23a and 23b not only function to fix terminal block 70, but also serve to fix a part of the automatic winding machine when winding first wire 41c and second wire 42c around winding core 21 by the automatic winding machine.

[0066] Terminal block fixing portions 23a and 23b have a substantially flat plate shape (substantially rectangular parallelepiped shape) with surfaces substantially parallel to the XY plane and have a predetermined thickness in the Z axis direction. The width of terminal block fixing portions 23a and 23b along the X axis direction is greater than the width of winding core portion 21 along the X axis direction and is substantially equal to the width of the upper portions of flange main bodies 220a and 220b along the X axis direction. Terminal block fixing portion 23a is integrally connected to the outer surface of flange main body 220a of flange portion 22a in the Y axis direction and protrudes outward from that surface in the Y axis direction. Terminal block fixing portion 23b is integrally connected to the outer surface of flange main body 220b of flange portion 22b in the Y axis direction and protrudes outward from that surface in the Y axis direction.

[0067] An extended flange 25a is formed above the flange main body 220a. The extended flange 25a is integrally connected to the upper part of the flange main body 220a and extends approximately parallel to the XZ plane relative to the flange main body 220a. In other words, the extended flange 25a has a shape that extends the flange main body 220a upward, and constitutes a part of the flange main body 220a. The extended flange 25a has a predetermined thickness in the Y-axis direction and has a surface that is approximately parallel to the XZ plane.

[0068] The fixing flange 24a is formed on the upper end of the flange main body 220a on the negative side in the X-axis direction, while the extension flange 25a is formed on the upper end of the flange main body 220a on the positive side in the X-axis direction. The extension flange 25a is disposed at a predetermined interval along the X-axis direction relative to the fixing flange 24a, and protrudes above the fixing main body 230a of the terminal block fixing part 23a.

[0069] A partition 26a is formed between the fixing flange 24a and the extended flange 25a. The fixing flange 24a, the extended flange 25a, and the partition 26a are arranged along the X-axis direction. The partition 26a is integrally connected to the upper part of the flange main body 220a and extends approximately parallel to the XZ plane relative to the flange main body 220a. In other words, the partition 26a has a shape that extends the flange main body 220a upward, and constitutes a part of the flange main body 220a. The partition 26a has a predetermined thickness in the Y-axis direction and has a surface that is approximately parallel to the XZ plane.

[0070] An extension flange 25b and a partition 26b are formed above flange main body 220b. The configurations of extension flange 25b and partition 26b are similar to the configurations of extension flange 25a and partition 26a, and therefore detailed description thereof will be omitted.

[0071] A notch 27a is formed between fixing flange 24a and partition 26a, and a notch 28a is formed between extension flange 25a and partition 26a. Either one of lead portions 41a or 41b of first wire 41c (FIG. 3) can be inserted into notch 27a. The same applies to notch 28a.

[0072] A notch 27b is formed between fixing flange 24b and partition 26b, and a notch 28b is formed between extension flange 25b and partition 26b. Either one of lead portions 42a or 42b of second wire 42c (FIG. 3) can be inserted into notch 27b. The same applies to notch 28b.

[0073] 2A, of the lead portions 41a and 41b, the lead portion 41a is inserted through the notch 27a, and the lead portion 41a is drawn from the inside to the outside in the Y-axis direction of the flange portion 22a via the notch 27a, and is also drawn from the outside in the Y-axis direction of the flange portion 22a toward the terminal block 70. Therefore, when the lead portion 41a is drawn toward the terminal block 70, unnecessary routing of the lead portion 41a can be prevented.

[0074] On the other hand, lead portion 41b does not pass through either notch 27a or 28a, but is drawn out from the inside of flange 22a in the Y-axis direction toward terminal block 70. As a result, lead portion 41a passes outside fixing flange 24a in the Y-axis direction, and lead portion 41b passes inside fixing flange 24a in the Y-axis direction, so that lead portion 41a and lead portion 41b can be well insulated from each other via fixing flange 24a.

[0075] Furthermore, since a partition portion 26a is formed between the notch portion 27a and the notch portion 28a, the partition portion 26a can adjust the position of the lead portion 41a that passes through the notch portion 27a and prevent the lead portion 41a from shifting out of position.

[0076] Of lead portions 42a and 42b, lead portion 42a is inserted through cutout portion 27b, and lead portion 42a is drawn from the inside to the outside in the Y-axis direction of flange portion 22b via cutout portion 27b, and is also drawn from the outside in the Y-axis direction of flange portion 22b toward terminal block 70. Therefore, when lead portion 42a is drawn toward terminal block 70, unnecessary routing of lead portion 42a can be prevented.

[0077] On the other hand, lead portion 42b does not pass through either notch 27b or 28b, but is drawn out from the inside of flange 22b in the Y-axis direction toward terminal block 70. As a result, lead portion 42a passes outside fixing flange 24b in the Y-axis direction, and lead portion 42b passes inside fixing flange 24b in the Y-axis direction, so that lead portion 42a and lead portion 42b can be well insulated from each other via fixing flange 24b.

[0078] Since a partition portion 26b is formed between the notch portion 27b and the notch portion 28b, the partition portion 26b can adjust the position of the lead portion 42a that passes through the notch portion 27b, and the partition portion 26b can also prevent the lead portion 42a from shifting in position.

[0079] 2B and 5, an insulating partition 30 is formed in the upper portion of the outer circumferential surface of the winding core 21. The insulating partition 30 is formed in approximately the center of the winding core 21 in the axial direction. That is, the insulating partition 30 is disposed between the first coil portion 41 and the second coil portion 42 disposed on the winding core 21, and has the function of insulating the first coil portion 41 from the second coil portion 42. Note that the insulating partition 30 is not essential and may be omitted.

[0080] The insulating partition portion 30 protrudes upward, and the protruding width is preferably greater than the radial thickness of the first coil portion 41 or the radial thickness of the second coil portion 42. This makes it possible for the insulating partition portion 30 to prevent the first coil portion 41 and the second coil portion 42 from being misaligned along the axial direction of the winding core portion 21. The radial thickness of the first coil portion 41 is approximately equal to twice the diameter of the first wire 41c, and the radial thickness of the second coil portion 42 is approximately equal to three times the diameter of the second wire 42c.

[0081] The insulating partition portion 30 has a predetermined width in the X-axis direction and is formed continuously from one end to the other end of the winding core portion 21 in the X-axis direction in the upper portion of the outer peripheral surface of the winding core portion 21. A partition recess 300 is formed in the insulating partition portion 30. The partition recess 300 is a recess for removing weight and is formed mainly to reduce the weight of the bobbin 20. The partition recess 300 is a recess that recesses downward from the upper end of the insulating partition portion 30 and opens upward in a substantially rectangular shape. Therefore, the shape of the opening of the insulating partition portion 30 is a substantially square ring shape when viewed from the direction along the Z-axis direction (from above). The partition recess 300 is not essential and may be omitted.

[0082] As shown in Fig. 5, core installation portions 31a and 31b are formed on the outer peripheral surface of winding core 21. Core installation portions 31a and 31b are located approximately in the center of winding core 21 in the axial direction and are formed on side portions of the outer peripheral surface of winding core 21 along the circumferential direction of winding core 21. Core installation portions 31a and 31b have curved shapes that curve along the side portions of the outer peripheral surface of winding core 21. Core installation portion 31a is formed on a side portion of the outer peripheral surface of winding core 21 on the negative side of the X-axis, and core installation portion 31b is formed on a side portion of the outer peripheral surface of winding core 21 on the positive side of the X-axis. Core installation portions 31a and 31b are arranged on opposite sides of each other in the X-axis direction.

[0083] The upper end of core installation portion 31a is connected to the end of insulating partition portion 30 on the negative side of the X-axis, and the lower end of core installation portion 31a is connected to the end of connecting portion 33 on the negative side of the X-axis. The upper end of core installation portion 31b is connected to the end of insulating partition portion 30 on the positive side of the X-axis, and the lower end of core installation portion 31b is connected to the end of connecting portion 33 on the positive side of the X-axis. In other words, core installation portions 31a and 31b, insulating partition portion 30, and connecting portion 33 are formed continuously along the circumferential direction of winding core portion 21 and are integrally formed. Therefore, core installation portions 31a and 31b, together with insulating partition portion 30, function to insulate first coil portion 41 (FIG. 3) and second coil portion 42 (FIG. 3) arranged on winding core portion 21.

[0084] Each of the core installation portions 31a and 31b has a recess 32. The recess 32 is recessed from the outer surface of the core installation portions 31a and 31b in the X-axis direction toward the inside in the X-axis direction or toward the inside in the radial direction of the winding core portion 21. Therefore, the inner surface of the recess 32 extends toward the outside in the radial direction of the winding core portion 21 (outside in the X-axis direction), and the recess 32 is open toward the outside in the radial direction of the winding core portion 21.

[0085] The shape of the space inside the recess 32 corresponds to the overall shape of the bypass cores 55a and 55b, and a space having a substantially rectangular parallelepiped shape is formed inside the recess 32. The recess 32 of the core installation section 31a can accommodate the bypass core 55a (FIG. 3), and the recess 32 of the core installation section 31b can accommodate the bypass core 55b (FIG. 3).

[0086] 8, the upper end of the inner wall surface of recess 32 is located below the upper part of the outer peripheral surface of winding core 21 and at approximately the same height as the upper part of the outer peripheral surface of middle leg 53a. The lower end of the inner wall surface of recess 32 is located above the lower part of the outer peripheral surface of winding core 21 and at approximately the same height as the lower part of the outer peripheral surface of middle leg 53a.

[0087] As shown in Fig. 5, core installation portion 31a has side walls 311 and 312, an upper wall 313, a lower wall 314, and a bottom wall 315. The same is true for core installation portion 31b, which has the same shape as core installation portion 31a. Bottom wall 315 forms the bottom of recess 32 and has a shape that is curved in a substantially C-shape along the circumferential direction of winding core 21 (see Fig. 8). Bottom wall 315 has a substantially rectangular shape when viewed in the X-axis direction.

[0088] Side wall portions 311 and 312, upper wall portion 313, and lower wall portion 314 rise from the peripheral edge of bottom wall portion 315. That is, core installation portions 31a and 31b have flange-like portions that protrude radially outward from winding core portion 21.

[0089] Side wall 311 rises from the side surface of bottom wall 315 on the positive side of the Y axis, and side wall 312 rises from the side surface of bottom wall 315 on the negative side of the Y axis. Side wall 311 and side wall 312 face each other in the Y axis direction and have surfaces that are approximately parallel to the XZ plane. Side wall 311 and 312 extend radially outward from winding core 21 or outward in the X axis direction.

[0090] The protruding length of the side wall portions 311 and 312 from the outer circumferential surface of the winding core portion 21 is determined, for example, according to the wire diameter of the first wire 41c (FIG. 3) or the wire diameter of the second wire 42c. In this embodiment, the first coil portion 41 and the second coil portion 42 are formed of two layers and three layers, respectively, in the radial direction of the winding core portion 21. Therefore, the protruding length is preferably at least twice the wire diameter of the first wire 41c (FIG. 3) or at least three times the wire diameter of the second wire 42c so that the side wall portions 311 and 312 can prevent misalignment of the first coil portion 41 and the second coil portion 42 along the Y-axis direction. In other words, the protruding length is preferably greater than the height of the first coil portion 41 or the second coil portion 42 from the outer circumferential surface of the winding core portion 21.

[0091] Upper wall portion 313 rises from the side surface of bottom wall portion 315 on the positive side of the Z axis, and lower wall portion 314 rises from the side surface of bottom wall portion 315 on the negative side of the Z axis. Upper wall portion 313 and lower wall portion 314 are disposed on opposite sides in the Z axis direction and have surfaces that are approximately parallel to the XY plane. Upper wall portion 313 and lower wall portion 314 extend radially outward from winding core portion 21 or outward in the X axis direction.

[0092] 8, in a state in which the bypass core 55a is accommodated inside the recess 32 of the core installation section 31a, a core inner surface 550a of the bypass core 55a abuts against the bottom wall portion 315 of the recess 32 and is disposed on a side portion of the outer circumferential surface of the winding core portion 21. A core outer surface 551a of the bypass core 55a does not protrude from the opening of the recess 32, and the bypass core 55a is installed in the core installation section 31a so that the entire bypass core 55a is accommodated inside the recess 32.

[0093] Furthermore, with the bypass core 55b accommodated inside the recess 32 of the core installation section 31b, a core inner surface 550b of the bypass core 55b abuts against the bottom wall 315 of the recess 32 and is disposed on a side portion of the outer circumferential surface of the winding core 21. A core outer surface 551b of the bypass core 55b does not protrude from the opening of the recess 32, and the bypass core 55b is installed in the core installation section 31b so that the entire bypass core 55b is accommodated inside the recess 32.

[0094] 3, the first coil portion 41 is arranged on one axial side of the winding core portion 21 relative to the core installation portion 31a, and the second coil portion 42 is arranged on the other axial side of the winding core portion 21 relative to the core installation portion 31a. That is, when the bypass cores 55a and 55b are installed in the core installation portions 31a and 31b, respectively, the bypass cores 55a and 55b are arranged so as to be sandwiched between the first coil portion 41 and the second coil portion 42.

[0095] 8, bypass core 55a is disposed between center leg 53a of core 50a and one of outer legs 52a, and between center leg 53a and one of outer legs 52a of core 50b. Bypass core 55b is disposed between center leg 53a of core 50a and the other outer leg 52a, and between center leg 53a of core 50a and the other outer leg 52a of core 50a. By disposing bypass cores 55a and 55b in such positions, it is possible to efficiently guide part of the magnetic flux generated in cores 50a and 50b into bypass cores 55a and 55b, and it is possible to accurately adjust the leakage characteristics between first coil portion 41 and second coil portion 42.

[0096] A (magnetic) gap G1a is formed between a core inner surface 550a of the bypass core 55a and a center leg outer surface 530a of the center leg 53a, and a gap G2a is formed between a core outer surface 551a of the bypass core 55a and an outer leg inner surface 520a of one of the outer legs 52a of the core 50a. By appropriately adjusting the widths of these gaps G1a and G2a, it is possible to adjust the leakage characteristics between the first coil portion 41 and the second coil portion 42. For example, as the gap G1a is made relatively larger (as the gap G2a is made relatively smaller), the leakage between the first coil portion 41 and the second coil portion 42 decreases, and as the gap G1a is made relatively smaller (as the gap G2a is made relatively larger), the leakage between the first coil portion 41 and the second coil portion 42 increases.

[0097] Similarly, a (magnetic) gap G1b is formed between a core inner surface 550b of bypass core 55b and a center leg outer surface 530a of center leg 53a, and a gap G2b is formed between a core outer surface 551a of bypass core 55a and an outer leg inner surface 520a of the other outer leg 52a of core 50a. By appropriately adjusting the widths of these gaps G1b and G2b, it is possible to adjust the leakage characteristics between the first coil portion 41 and the second coil portion 42. For example, as the gap G1b is made relatively larger (as the gap G2b is made relatively smaller), the leakage between the first coil portion 41 and the second coil portion 42 decreases, and as the gap G1b is made relatively smaller (as the gap G2b is made relatively larger), the leakage between the first coil portion 41 and the second coil portion 42 increases.

[0098] Note that the leakage characteristics between the first coil portion 41 and the second coil portion 42 can be adjusted not only by adjusting the gaps G1a, G2a, G1b, and G2b described above, but also by changing the size (thickness in the X-axis and Y-axis directions, length in the Z-axis direction) or shape of the bypass cores 55a and 55b. In particular, by appropriately adjusting the width of the bypass cores 55a and 55b along the X-axis direction, the same effect as when adjusting the gaps G1a, G2a, G1b, and G2b described above can be obtained.

[0099] As shown in FIG. 5, the connecting portion 33 is formed on the lower portion of the outer peripheral surface of the winding core portion 21, approximately in the axial center of the winding core portion 21, and extends along the X-axis direction. The end of the connecting portion 33 on the negative X-axis side is connected to the lower end of the core installation portion 31a, and the end of the connecting portion 33 on the positive X-axis side is connected to the lower end of the core installation portion 31b. An upwardly recessed recess is formed in the connecting portion 33 (see FIG. 2B). A mounting portion 29c is integrally formed at the lower end of the connecting portion 33. The mounting portion 29c extends approximately parallel to the connecting portion 33 along the XZ plane, and the bottom surface of the mounting portion 29c is approximately flat. The bobbin 20 is mounted on the case bottom 91 of the case 90 (FIG. 3) via the mounting portion 29c and the like.

[0100] As shown in FIG. 3, the terminal block 70 is formed separately from the bobbin 20 and is detachably attached to the bobbin 20. The terminal block 70 may be made of the same insulating material as the bobbin 20, but is preferably made of an insulating material that is more excellent in formability or heat resistance. The terminal block 70 is disposed on the side of the winding core 21 on the negative X-axis direction side, and is spaced apart from the outer circumferential surface of the winding core 21 in a direction perpendicular to the axial direction of the winding core 21 (X-axis direction). Therefore, a gap having a predetermined length in the X-axis direction is formed along the axial direction of the winding core 21 between the side portion of the outer circumferential surface of the winding core 21 and the terminal block 70 (see FIG. 8).

[0101] As shown in FIG. 6, the terminal block 70 has a terminal block base portion 71, side fixing portions 72a and 72b, planar fixing portions 73a and 73b, terminal block step portions 74a and 74b, lead insertion grooves 75a, 75b, 75c and 75d, terminal insertion holes 76a_1 and 76a_2, terminal insertion holes 76b_1 and 76b_2, cover mounting portions 77a and 77b, terminal block protrusions 78a and 78b, and a bottom protrusion 79 (FIG. 7).

[0102] 7, the terminal block base portion 71 is disposed on the side of the winding core portion 21 in the X-axis direction and substantially parallel to the axial direction of the winding core portion 21. The terminal block base portion 71 is disposed adjacent to the side of the bobbin 20 in the X-axis direction so as to bridge the gap between the flange portion 22a and the flange portion 22b of the bobbin 20 in the Y-axis direction.

[0103] The length of the terminal block base portion 71 along the Y-axis direction is approximately equal to the length of the bobbin 20 along the Y-axis direction. The terminal block base portion 71 (the bottom surface of the terminal block base portion 71) is disposed above the center portion of the winding core portion 21 in the Z-axis direction, at a position spaced apart in the X-axis direction from a side portion of the outer circumferential surface of the winding core portion 21, and is disposed above (or in the vicinity of) the upper portion of the outer circumferential surface of the winding core portion 21 (see FIG. 8). However, the height position at which the terminal block base portion 71 is installed is not limited to this, and the terminal block base portion 71 (the bottom surface of the terminal block base portion 71) may be disposed at a height position approximately equal to the upper portion of the outer circumferential surface of the winding core portion 21, or may be disposed at a lower position.

[0104] 6, side fixing portion 72a is formed on one side in the Y-axis direction of terminal block base portion 71, and side fixing portion 72b is formed on the other side in the Y-axis direction of terminal block base portion 71. Side fixing portions 72a and 72b protrude by a predetermined length from the end portion (side portion) of terminal block base portion 71 in the X-axis direction toward the positive side of the X-axis where bobbin 20 is located.

[0105] 2A, when terminal block 70 is fixed to terminal block fixing portions 23a and 23b of bobbin 20, side fixing portion 72a is disposed along the outer surface in the Y-axis direction of fixing flange 24a of bobbin 20, and the inner surface in the Y-axis direction of side fixing portion 72a (surface parallel to the XZ plane) is fixed to the outer surface in the Y-axis direction of fixing flange 24a. Furthermore, side fixing portion 72b is disposed along the outer surface in the Y-axis direction of fixing flange 24b of bobbin 20, and the inner surface in the Y-axis direction of side fixing portion 72b (surface parallel to the XZ plane) is fixed to the outer surface in the Y-axis direction of fixing flange 24b. This allows terminal block 70 to be attached to terminal block fixing portions 23a and 23b via side fixing portions 72a and 72b. In addition, when the side fixing portions 72a and 72b are fixed to the fixing flange portions 24a and 24b, the ends of the fixing flange portions 24a and 24b on the negative X-axis side are fixed to the side portions of the terminal block base portion 71 on the positive X-axis side.

[0106] 6, planar fixing portion 73a is formed at one end in the Y-axis direction of terminal block base portion 71, and planar fixing portion 73b is formed at the other end in the Y-axis direction of terminal block base portion 71. Planar fixing portions 73a and 73b are disposed further outward in the Y-axis direction than lateral fixing portions 72a and 72b.

[0107] Planar fixing portions 73a and 73b have surfaces (substantially rectangular surfaces having predetermined lengths in the X-axis and Y-axis directions) that are substantially parallel to the upper or lower surface of terminal block base portion 71. A step is formed between the upper surface of planar fixing portion 73a and the upper surface of lateral fixing portion 72a, and planar fixing portion 73a forms the lower surface of this step. Similarly, a step is formed between the upper surface of planar fixing portion 73b and the upper surface of lateral fixing portion 72b, and planar fixing portion 73b forms the lower surface of this step.

[0108] A terminal block step portion 74a is formed on the lower surface of the flat fixing portion 73a, and a terminal block step portion 74b is formed on the lower surface of the flat fixing portion 73b. The terminal block step portion 74a has a step lower surface 740a consisting of a surface (a substantially rectangular surface having a predetermined length in the X-axis direction and a Y-axis direction) that is approximately parallel to the upper surface or the lower surface of the terminal block base portion 71. The terminal block step portion 74b has a step lower surface 740b consisting of a surface (a substantially rectangular surface having a predetermined length in the X-axis direction and a Y-axis direction) that is approximately parallel to the upper surface or the lower surface of the terminal block base portion 71. The step lower surface 740a constitutes the lower surface of the step formed between the lower surface of the terminal block step portion 74a and the lower surface of the terminal block protrusion portion 78a, and the step lower surface 740b constitutes the lower surface of the step formed between the lower surface of the terminal block step portion 74b and the lower surface of the terminal block protrusion portion 78b.

[0109] As shown in Fig. 7, the terminal block step portion 74b engages with the terminal block fixing portion 23b of the bobbin 20. More specifically, the terminal block step portion 74b engages with the terminal block fixing portion 23b when the step lower surface 740b of the terminal block step portion 74b abuts against the upper surface of the terminal block fixing portion 23b. Although not shown in detail, the terminal block step portion 74a and the terminal block fixing portion 23a also engage in a similar manner. The terminal block step portions 74a and 74b engage with the terminal block fixing portions 23a and 23b of the bobbin 20, thereby fixing the flat fixing portions 73a and 73b to the terminal block fixing portions 23a and 23b.

[0110] Bottom surface protrusion 79 protrudes downward from the bottom surface of terminal block base portion 71 and is formed from one end to the other end of terminal block base portion 71 in the Y-axis direction. On the X-axis positive side of bottom surface protrusion 79, terminal block step portions 74a and 74b engage with terminal block fixing portions 23a and 23b of bobbin 20, as described above. At this time, the end (tip) of terminal block fixing portion 23b on the X-axis negative side is fixed to the side surface of bottom surface protrusion 79 on the X-axis positive side. Although detailed illustration is omitted, the end (tip) of terminal block fixing portion 23a on the X-axis negative side is similarly fixed to the side surface of bottom surface protrusion 79 on the X-axis positive side.

[0111] On the other hand, on the negative X-axis side of bottom surface protrusion 79, the end portion in the X-axis direction of cover bottom 81 of cover portion 80 (FIG. 3) can be fixed to the bottom surface of terminal block base 71. When cover bottom 81 is fixed to terminal block base 71, the end portion (tip portion) on the positive X-axis side of cover bottom 81 abuts against the side surface on the negative X-axis side of bottom surface protrusion 79, thereby making it possible to prevent displacement of cover portion 80 in the X-axis direction.

[0112] In this manner, in this embodiment, as shown in FIG. 2A, by engaging the side fixing portions 72a and 72b with the fixing flange portions 24a and 24b as the first engaging portions, it is possible to prevent the terminal block 70 from shifting in position along the Y-axis direction relative to the terminal block fixing portions 23a and 23b.

[0113] Furthermore, as shown in FIG. 7, by engaging the terminal block step portions 74a and 74b with the terminal block fixing portions 23a and 23b as a second engaging portion (i.e., by fixing the flat fixing portions 73a and 73b with the terminal block fixing portions 23a and 23b), it is possible to prevent misalignment of the terminal block 70 along the Z-axis direction relative to the terminal block fixing portions 23a and 23b.

[0114] Furthermore, by engaging the bottom surface protrusion 79 with the terminal block fixing portions 23a and 23b as a third engaging portion, it is possible to prevent the terminal block 70 from shifting in position along the X-axis direction relative to the terminal block fixing portions 23a and 23b. This allows the terminal block 70 to be attached to the terminal block fixing portions 23a and 23b with sufficient fixing strength.

[0115] Furthermore, by engaging the above-mentioned engaging portions, the terminal block 70 can be connected to one end and the other end in the axial direction of the winding core 21, and can be arranged approximately parallel to the axial direction of the winding core 21. The terminal block 70 is fixed to the terminal block fixing portions 23a and 23b mainly by three-point support at the above-mentioned engaging portions, and may be fixed (reinforced) with an adhesive or the like as needed. Note that any of the above-mentioned engaging portions may be omitted.

[0116] 6, cover attachment portion 77a is formed on one end (end face) in the Y-axis direction of terminal block base portion 71, and cover attachment portion 77b is formed on the other end (end face) in the Y-axis direction of terminal block base portion 71. Cover attachment portions 77a and 77b have substantially flat surfaces, and Y-axis direction ends of cover side portion 82 (FIG. 3) of cover portion 80 are fixed to cover attachment portions 77a and 77b.

[0117] Terminal block protrusion 78a is formed on one end (end face) of terminal block base 71 in the Y-axis direction and protrudes a predetermined length outward in the Y-axis direction relative to cover mounting portion 77a. Terminal block protrusion 78b is formed on the other end (end face) of terminal block base 71 in the Y-axis direction and protrudes a predetermined length outward in the Y-axis direction relative to cover mounting portion 77a. Terminal block protrusions 78a and 78b are formed continuously from the upper end to the lower end of cover mounting portions 77a and 77b, respectively, at the ends in the X-axis direction of cover mounting portions 77a and 77b.

[0118] A step is formed between the terminal block protrusion 78a and the cover mounting portion 77a, and the cover mounting portion 77a forms the underside of the step. A step is formed between the terminal block protrusion 78b and the cover mounting portion 77b, and the cover mounting portion 77b forms the underside of the step. One end of the cover side portion 82 of the cover portion 80 in the Y-axis direction engages with the step between the terminal block protrusion 78a and the cover mounting portion 77a, so that the cover mounting portion 77a prevents misalignment in the Y-axis direction and the terminal block protrusion 78a prevents misalignment in the X-axis direction. Furthermore, the other end of the cover side portion 82 of the cover portion 80 in the Y-axis direction engages with the step between the terminal block protrusion 78b and the cover mounting portion 77b, so that the cover mounting portion 77b prevents misalignment of the cover portion 80 in the Y-axis direction and the terminal block protrusion 78b prevents misalignment of the cover portion 80 in the X-axis direction.

[0119] The terminal insertion holes 76a_1 and 76a_2 are each formed adjacent to one side in the Y-axis direction of the terminal block base portion 71. The terminal insertion hole 76a_1 is disposed further outward in the Y-axis direction than the terminal insertion hole 76a_2. The terminal insertion holes 76a_1 and 76a_2 can be configured to fix the terminals 61_1 and 61_2, respectively.

[0120] The terminal insertion holes 76a_1 and 76a_2 are formed as holes bent in a substantially L-shape corresponding to the shapes of the terminals 61_1 and 61_2. The terminals 61_1 and 61_2 are fixed to the terminal insertion holes 76a_1 and 76a_2 by integral molding (insert molding).

[0121] The terminal insertion holes 76b_1 and 76b_2 are formed adjacent to each other on the other side in the Y-axis direction of the terminal block base portion 71. The terminal insertion hole 76b_1 is disposed further outward in the Y-axis direction than the terminal insertion hole 76b_2. The terminal insertion holes 76b_1 and 76b_2 can be configured to fix the terminals 62_1 and 62_2, respectively.

[0122] The terminal insertion holes 76b_1 and 76b_2 are formed as holes bent in a substantially L-shape corresponding to the shapes of the terminals 62_1 and 62_2. The terminals 62_1 and 62_2 are fixed to the terminal insertion holes 76b_1 and 76b_2 by integral molding (insert molding).

[0123] The lead insertion groove 75a is arranged adjacent to one side in the Y-axis direction of the terminal insertion hole 76a_1, and the lead insertion groove 75b is arranged adjacent to one side in the Y-axis direction of the terminal insertion hole 76a_2. The lead insertion groove 75c is arranged adjacent to the other side in the Y-axis direction of the terminal insertion hole 76b_2, and the lead insertion groove 75d is arranged adjacent to the other side in the Y-axis direction of the terminal insertion hole 76b_1.

[0124] The lead insertion grooves 75a to 75d are recessed grooves that are recessed downward from the upper surface of the terminal block base portion 71. The lead insertion grooves 75a and 75d extend along the X-axis direction from the outer end of the terminal block base portion 71 in the X-axis direction to the flat fixing portion 73a. The lead insertion grooves 75b and 75c extend along the X-axis direction from the outer end of the terminal block base portion 71 in the X-axis direction to the inner end of the terminal block base portion 71 in the X-axis direction.

[0125] 2A and 6, the lead portion 41a of the first wire 41c is inserted into the lead insertion groove 75a, and the lead portion 41b of the first wire 41c is inserted into the lead insertion groove 75b. The lead portion 42b of the second wire 42c is inserted into the lead insertion groove 75c, and the lead portion 42a of the second wire 41c is inserted into the lead insertion groove 75d.

[0126] Terminals 61_1, 61_2, 62_1, and 62_2 are attached to terminal block 70 at predetermined intervals along the Y-axis direction. Terminals 61_1 and 61_2 have the same shape and are fixed to terminal insertion holes 76a_1 and 76a_2, respectively. A lead portion 41a of a first wire 41c is connected to terminal 61_1, and a lead portion 41b of the first wire 41c is connected to terminal 61_2.

[0127] The terminals 62_1 and 62_2 have the same shape and are fixed to the terminal insertion holes 76b_1 and 76b_2, respectively. The lead portion 42a of the second wire 42c is connected to the terminal 62_1, and the lead portion 42b of the second wire 42c is connected to the terminal 62_2.

[0128] The terminal 61_1 has an external connection portion 610_1, a coupling portion 611_1, a wire connection bottom portion 612_1, and a wire connection folded portion 613_1. The external connection portion 610_1 is a portion that is connected to a mounting board, and protrudes from the upper portion of the terminal insertion hole 76a_1 and extends upward. The external connection portion 610_1 protrudes upward beyond the upper edge of the case 90 (FIG. 1).

[0129] The coupling portion 611_1 is a portion that couples the external connection portion 610_1 and the connecting wire bottom portion 612_1, and extends toward the negative X-axis direction while bending outward in the Y-axis direction.

[0130] The connecting wire bottom portion 612_1 and the connecting wire folded portion 613_1 are portions that connect the lead portion 41a, and are capable of sandwiching (crimping) the lead portion 41a between the connecting wire bottom portion 612_1 and the connecting wire folded portion 613_1. The connecting wire folded portion 613_1 is integrally connected to the outer end portion in the Y-axis direction of the connecting wire bottom portion 612_1, and is disposed opposite the connecting wire bottom portion 612_1 in the Z-axis direction.

[0131] The terminal 61_2 has an external connection portion 610_2, a coupling portion 611_2, a wire connection bottom portion 612_2, and a wire connection folded-back portion 613_2. The shapes and functions of the parts constituting the terminal 61_2 are similar to those of the parts constituting the terminal 61_1, and therefore detailed description thereof will be omitted.

[0132] The terminal 62_1 has an external connection portion 620_1, a coupling portion 621_1, a wire connection bottom portion 622_1, and a wire connection folded-back portion 623_1. The terminal 62_1 differs from the terminal 61_1 in that the terminal 62_1 is formed symmetrically with respect to the X-axis, but is otherwise the same as the terminal 61_1. Therefore, detailed description of the terminal 62_1 will be omitted.

[0133] The terminal 62_2 has an external connection portion 620_2, a coupling portion 621_2, a wire connection bottom portion 622_2, and a wire connection folded-back portion 623_2. The terminal 62_2 differs from the terminal 61_2 in that it is formed symmetrically with respect to the X-axis, but has other features in common with the terminal 61_2, and therefore detailed description of the terminal 62_2 will be omitted.

[0134] 3, the cover portion 80 has a cover bottom portion 81 and a cover side portion 82. The cover portion 80 is formed separately from the terminal block 70, and is detachably attached to the terminal block 70 so as to be disposed around the terminal block 70.

[0135] The cover bottom 81 has a plate surface that is approximately parallel to the XY plane, and is disposed below the terminals 61_1 and 61_2 and the terminals 62_1 and 62_2 that are attached to the terminal block 70. The cover bottom 81 is fixed to the underside of the terminal block base 71 of the terminal block 70 with its tip in the X-axis direction abutting against the bottom surface protrusion 79 of the terminal block 70. Fixing the cover bottom 81 to the underside of the terminal block base 71 in this manner makes it possible to prevent the cover 80 from shifting in the X-axis and Z-axis directions relative to the terminal block 70.

[0136] The cover side portions 82 extend upward and rise from the peripheral edge of the cover bottom portion 81 in a state substantially perpendicular to the cover bottom portion 81. The cover side portions 82 are formed continuously on both ends of the cover bottom portion 81 in the Y-axis direction and on the outer end portion in the X-axis direction.

[0137] By forming the cover bottom portion 81 and the cover side portion 82 on the cover portion 80, the terminals 61_1 and 61_2 and the terminals 62_1 and 62_2 attached to the terminal block 70 can be protected from external forces, etc. Furthermore, the cover bottom portion 81 and the cover side portion 82 can provide good insulation between the terminals 61_1 and 61_2 and the core 50a, and also provide good insulation between the terminals 62_1 and 62_2 and the core 50b.

[0138] Next, a method for manufacturing the coil device 10 will be described with reference to Fig. 3 and other figures. First, the components shown in Fig. 3 are prepared. Terminals 61_1 and 61_2 and terminals 62_1 and 62_2 are attached to the terminal block 70 in advance by insert molding or the like. In addition, a cover portion 80 is attached to the terminal block 70 in advance. These may be attached using connecting members such as adhesives or fasteners.

[0139] Next, the first wire 41c and the second wire 42c are wound around the outer peripheral surface of the winding core 21 of the bobbin 20, forming the first coil portion 41 on one side in the Y-axis direction of the insulating partition 30 and the second coil portion 42 on the other side. The lead portions 41a and 41b of the first wire 41c are drawn out from one end of the winding core 21 in the axial direction. The lead portions 42a and 42b of the second wire 42c are drawn out from the other end of the winding core 21 in the axial direction.

[0140] Next, one end of the terminal block 70 in the Y-axis direction is fixed to the terminal block fixing portion 23a of the bobbin 20, and the other end of the terminal block 70 in the Y-axis direction is fixed to the terminal block fixing portion 23b of the bobbin 20, and the terminal block 70 is positioned outside (to the side) in the X-axis direction away from the outer peripheral surface of the winding core portion 21.

[0141] Next, the lead portion 41a is connected to the terminal 61_1 by crimping or the like, the lead portion 41b is connected to the terminal 61_2 by crimping or the like, the lead portion 42a is connected to the terminal 62_1 by crimping or the like, and the lead portion 42b is connected to the terminal 62_2 by crimping or the like (see FIG. 2). Next, the center leg portion 53a of the core 50a and the center leg portion 53b of the core 50b are inserted into the through hole 211 of the bobbin 20, and the cores 50a and 50b are attached to the bobbin 20.

[0142] The bypass core 55a is fitted (press-fitted) into the recess 32 of the core installation portion 31a, and the bypass core 55b is fitted (press-fitted) into the recess 32 (FIG. 5) of the core installation portion 31b. The bypass cores 55a and 55b may be integrally molded with the core installation portions 31a and 31b by insert molding. The bypass cores 55a and 55b may also be fixed to the recess 32 with an adhesive or the like. The timing at which the cores 50a and 50b and the bypass cores 55a and 55b are attached to the bobbin 20 may be changed as appropriate.

[0143] Next, the bobbin 20 and other components are housed inside the case 90, and the case 90 is filled with potting resin 100, thereby obtaining the coil device 10 shown in FIG.

[0144] As described above, in the coil device 10 according to the present embodiment, as shown in FIGS. 3 and 5 , the outer peripheral surface of the winding core 21 is formed with core installation portions 31a and 31b, which open toward the radially outer side of the winding core 21 or the outer side in the X-axis direction and have recesses 32 capable of accommodating the bypass cores 55a and 55b. Therefore, the bypass cores 55a and 55b can be accommodated inside the recesses 32 from the radially outer side of the winding core 21 through the openings, and the bypass cores 55a and 55b can be stably fixed to the core installation portions 31a and 31b. Therefore, unlike the conventional technology, there is no need to use multiple bobbins to fix the bypass cores 55a and 55b, which contributes to a reduction in the number of parts and man-hours and enables the coil device 10 to be made more compact.

[0145] Furthermore, because there is no need to consider combinations with other bobbins, the bobbin 20 and the bypass cores 55a and 55b do not require as high dimensional accuracy as in the prior art, which contributes to improving the performance of the coil device 10. Furthermore, when accommodating the bypass cores 55a and 55b inside the recess 32, high alignment accuracy is not required, which improves workability.

[0146] In addition, by adjusting the size of the bypass cores 55a and 55b so that the bypass cores 55a and 55b are positioned on the side portions of the outer peripheral surface of the winding core portion 21, the coil device 10 can be effectively made smaller (lower in height).

[0147] Furthermore, even when the size or shape of the bypass cores 55a and 55b is changed to adjust the leakage characteristics between the first coil portion 41 and the second coil portion 42, the interior of the recess 32 can accommodate bypass cores 55a and 55b of various sizes or shapes, and this allows for flexible response to changes in the size or shape of the bypass cores 55a and 55b without changing the shape of the bobbin 20.

[0148] Furthermore, in this embodiment, the first coil portion 41 is disposed on one axial side of the winding core portion 21 relative to the core installation portions 31a and 31b, and therefore the second coil portion 42 is disposed on the other axial side of the winding core portion 21 relative to the core installation portions 31a and 31b. Therefore, the core installation portions 31a and 31b are formed between the first coil portion 41 and the second coil portion 42, and it becomes possible to dispose the bypass cores 55a and 55b between the first coil portion 41 and the second coil portion 42, thereby enabling the leakage characteristics between the first coil portion 41 and the second coil portion 42 to be adjusted with high precision.

[0149] Furthermore, because the core installation portions 31a and 31b are formed on the side portions of the outer peripheral surface of the winding core portion 21, the bypass cores 55a and 55b are disposed on the sides of the winding core portion 21, thereby enabling a low profile of the coil device 10. Furthermore, because the inner wall surface of the recess 32 extends radially outward from the winding core portion 21, it becomes possible to accommodate the bypass cores 55a and 55b in the recess 32 by fitting them from the radially outward side of the winding core portion 21, for example, and this makes it easy to install the bypass cores 55a and 55b on the bobbin 20.

[0150] 8, the inner surface of bypass core 55a is curved along center leg outer surface 530a of center leg 53a, and therefore the distance between core inner surface 550a of bypass core 55a and center leg outer surface 530a is approximately constant in the curved portion of bypass core 55a. This prevents a localized area of ​​low magnetic resistance from being formed therebetween, and prevents abnormal heat generation in bypass core 55a or center leg 53a.

[0151] 3, since the terminal block 70 is formed separately from the bobbin 20, during manufacturing of the coil device 10, the first wire 41c and the second wire 42c can be wound around the outer peripheral surface of the winding core 21 with the terminal block 70 removed from the bobbin 20, and this prevents the terminal block 70 from interfering with automatic winding by the automatic winding machine, particularly when winding the first wire 41c and the second wire 42c using an automatic winding machine. Also, by forming (only) the terminal block 70 from a highly heat-resistant resin separately from the bobbin 20, a heat-resistant coil device 10 can be realized at low cost.

[0152] Furthermore, by positioning the terminal block 70 at a position spaced apart laterally from the outer peripheral surface of the winding core portion 21, it is possible to reduce the size (length) of the coil device 10 in the axial direction of the winding core portion 21 compared to when the terminal block 70 is formed at the axial end of the winding core portion 21, thereby making it possible to miniaturize the coil device 10.

[0153] Second embodiment The coil device 110 according to the second embodiment of the present invention is similar in configuration to the first embodiment described above, with only the following differences, and provides similar effects. In the drawings, members common to the first embodiment are designated by the same reference numerals, and descriptions of overlapping parts will be omitted.

[0154] As shown in Fig. 9, the coil device 110 has a bobbin 120, and the bobbin 120 has insulating partitions 130a and 130b. As shown in Fig. 10, the insulating partitions 130a and 130b are formed at one end and the other end in the X-axis direction, respectively, in an upper portion of the outer circumferential surface of the winding core 21. That is, in this embodiment, unlike the insulating partition 30 of the first embodiment shown in Fig. 5, the insulating partition 30 is not formed so as to cross the upper portion of the outer circumferential surface of the winding core 21 in the X-axis direction, but two insulating partitions 130a and 130b are arranged at a predetermined interval in the X-axis direction in the upper portion of the outer circumferential surface of the winding core 21.

[0155] A communicating path 34 is formed between the insulating partition portion 130a and the insulating partition portion 130b. The communicating path 34 extends along the Y-axis direction, and the first wire 41c can be inserted through the communicating path 34. This allows the first wire 41c to be wound via the communicating path 34 from one side of the insulating partition portions 130a and 130b in the Y-axis direction to the other side of the insulating partition portions 130a and 130b in the Y-axis direction, and the first wire 41c to be wound via the communicating path 34 from the other side of the insulating partition portions 130a and 130b in the Y-axis direction to one side of the insulating partition portions 130a and 130b in the Y-axis direction.

[0156] This embodiment also provides the same effects as the first embodiment. In addition, in this embodiment, since the communication path 34 is formed between the insulating partitions 130a and 130b, the formation area of ​​the first coil portion 41 can be extended to the other side in the Y-axis direction beyond the insulating partitions 130a and 130b, and the number of turns of the first coil portion 41 can be increased. Note that the formation area of ​​the second coil portion 42 may be extended to one side in the Y-axis direction beyond the insulating partitions 130a and 130b, in which case the number of turns of the second coil portion 42 can be increased.

[0157] The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present invention.

[0158] In the above embodiments, examples of application of the present invention to a leakage transformer have been described, but the present invention can also be applied to other coil devices in addition to leakage transformers.

[0159] In each of the above embodiments, the bypass cores 55a and 55b are disposed on the side portions of the outer circumferential surface of the winding core 21, but the positions of the bypass cores 55a and 55b are not limited to this and may be changed as appropriate. For example, the bypass cores 55a and 55b may be disposed on the upper portion or lower portion of the outer circumferential surface of the winding core 21. Alternatively, the bypass cores 55a and 55b may be disposed so as to straddle the side portions and upper portion (or the side portions and lower portion) of the outer circumferential surface of the winding core 21.

[0160] In the above embodiments, the cores 50a and 50b are each configured as an E-shaped core, but one of the cores 50a and 50b may be configured as an E-shaped core and the other as an I-shaped core. Alternatively, the core 50a may be configured as a combination of two U-shaped cores, and the core 50b may be configured as a combination of two U-shaped cores.

[0161] In the first embodiment, lead portion 41a may be inserted into notch 28a shown in Fig. 2A. Furthermore, of lead portions 41a and 41b, lead portion 41b may be inserted into notch 27a or notch 28a.

[0162] Similarly, lead portion 42a may be inserted through cutout portion 28b. Of lead portions 42a and 42b, lead portion 42b may be inserted through cutout portion 27b or cutout portion 28b.

[0163] 5, the core installation portions 31a and 31b are formed in the approximate center of the winding core 21 in the Y-axis direction, but they may be formed in positions shifted to one side or the other in the Y-axis direction from that position. In other words, the bypass cores 55a and 55b may be disposed in positions shifted to one side or the other in the Y-axis direction from the approximate center of the winding core 21 in the Y-axis direction.

[0164] In each of the above embodiments, only one terminal block 70 is provided on one side in the X-axis direction of the outer peripheral surface of the winding core 21, but two terminal blocks 70 may be provided on both sides in the X-axis direction of the outer peripheral surface of the winding core 21. Furthermore, two terminal blocks 70 may be formed on both ends of the winding core 21 in the axial direction.

[0165] In each of the above embodiments, two coil portions (first coil portion 41 and second coil portion 42) are formed on winding core portion 21, but three or more coil portions may be formed.

[0166] In the first embodiment, the bobbin 20 is provided with two bypass cores 55a and 55b, but the number of bypass cores may be one, or three or more. The same applies to the second embodiment. [Explanation of symbols]

[0167] 10,110... Coil device, 20,120... Bobbin, 21... Winding core portion, 211... Through hole, 22a, 22b... Flange portion, 220a, 220b... Flange portion main body, 23a, 23b... Terminal block fixing portion, 24a, 24b... Fixing flange portion, 25a, 25b... Extension flange portion, 26a, 26b... Partition portion, 27a, 27b, 28a, 28b... Cutout portion, 29a, 29b, 29c... Placement portion, 30,130a, 130b... Insulating partition portion, 300... Partition recess, 31a, 31b... Core installation portion, 311, 312... Side wall portion, 313... Upper wall portion, 314... Lower wall portion, 315...bottom wall portion, 32...recess, 33...connecting portion, 34...communicating passage, 41...first coil portion, 42...second coil portion, 41a, 41b...first lead portion, 41c...first wire, 42a, 42b...second lead portion, 42c...second wire, 50a, 50b...core (main core), 51a, 51b...base portion, 52a, 52b...outer leg portion, 520a, 520b...inner surface of outer leg, 53a, 53b...middle leg portion, 530a, 530b...outer surface of middle leg, 55a, 55b...bypass core, 550a, 550b...core inner surface, 551a, 551b...outer surface of core, 552a, 552b, 553a, 553b...side surface of core, 554a, 554b...upper surface of core, 555a, 555b...lower surface of core, 61_1, 61_2, 62_1, 62_2...terminal, 610_1, 610_2, 620_1, 620_2...external connection portion, 611_1, 611_2, 621_1, 621_2...connection portion, 612_1, 612_2, 622_1, 622_2...bottom of connection wire, 613_1, 613_2, 623_1, 623_2...connection wire fold-back portion, 70...terminal block, 71...terminal block base portion , 72a, 72b...side fixing portion, 73a, 73b...flat fixing portion, 74a, 74b...terminal block step portion, 740a, 740b...step bottom surface, 75a, 75b, 75c, 75d...lead insertion groove, 76a_1, 76a_2, 76b_1, 76b_2...terminal insertion hole, 77a, 77b...cover mounting portion, 78a, 78b...terminal block protrusion portion, 79...bottom protrusion portion, 80...cover portion, 81...cover bottom portion, 83...cover side portion, 90...case, 91...case bottom, 92...case side, 93...joint portion, 100...potting resin.

Claims

1. a bobbin having a winding core on which the first coil portion and the second coil portion are arranged; a main core attached to the bobbin; a bypass core attached to the bobbin for bypassing a portion of the magnetic flux generated in the main core, a core installation portion is formed on an outer peripheral surface of the winding core portion, the core installation portion having a recess that opens toward the outside in the radial direction of the winding core portion and is capable of accommodating the bypass core, the recess has a bottom wall portion extending along the outer peripheral surface of the winding core portion, a pair of side wall portions rising from the peripheral edge of the bottom wall portion and opposing each other along the axial direction of the winding core portion, and an upper wall portion and a lower wall portion rising from the peripheral edge of the bottom wall portion, connected to the pair of side wall portions, and opposing each other; The coil device wherein the bypass core is entirely housed within the recess.

2. the core installation portion has a portion that protrudes radially outward from the winding core portion, the first coil portion is disposed on one axial side of the winding core portion relative to the core installation portion, The coil device according to claim 1 , wherein the second coil portion is disposed on the other axial side of the winding core portion relative to the core installation portion.

3. the core installation portion is formed on a side portion of an outer peripheral surface of the winding core portion along a circumferential direction of the winding core portion, The coil device according to claim 1 or 2, wherein an inner surface of the recessed portion extends radially outward of the winding core portion.

4. a through hole extending along the axial direction of the winding core portion is formed in the winding core portion, the main core has a center leg portion disposed inside the through hole and an outer leg portion disposed outside the winding core portion, 4. The coil device according to claim 1, wherein the bypass core is disposed between the center leg portion and the outer leg portion.

5. the bypass core has a columnar shape, The coil device according to claim 4 , wherein the inner surface of the bypass core is curved along the outer surface of the middle leg portion.

6. the middle leg portion and the outer leg portion each extend along a first axis and are arranged at a predetermined interval along a second axis perpendicular to the first axis, 6. The coil device according to claim 4, wherein, with respect to a third axis perpendicular to the first axis and the second axis, the cross-sectional area on one side of the center of the middle leg is larger than the cross-sectional area on the other side of the center of the middle leg.

7. a case for accommodating the bobbin; a potting resin filled in the case, A coil device according to any one of claims 4 to 6, wherein the cross-sectional area of ​​the bottom surface side of the case relative to the center of the middle leg is larger than the cross-sectional area of ​​the opening side of the case relative to the center of the middle leg.

8. a terminal block formed separately from the bobbin and attached to one end and the other end in the axial direction of the bobbin; 8. The coil device according to claim 1, wherein the terminal block is arranged at a position spaced apart laterally from the outer peripheral surface of the winding core portion.

9. A bobbin having a winding core portion on which a first coil portion and a second coil portion are arranged; a main core attached to the bobbin; a bypass core attached to the bobbin for bypassing a portion of the magnetic flux generated in the main core; a case for accommodating the bobbin; a potting resin filled in the case, a core installation portion is formed on an outer peripheral surface of the winding core portion, the core installation portion having a recess that opens toward the outside in the radial direction of the winding core portion and is capable of accommodating the bypass core, a through hole extending along the axial direction of the winding core portion is formed in the winding core portion, the main core has a center leg portion disposed inside the through hole and an outer leg portion disposed outside the winding core portion, the bypass core is disposed between the middle leg portion and the outer leg portion, The coil device has a cross-sectional area on the bottom side of the case from the center of the middle leg that is larger than a cross-sectional area on the opening side of the case from the center of the middle leg.

Images