Coil device

Abstract

To provide a coil device which can be made low-profile and has excellent heat dissipation while miniaturizing the device.SOLUTION: A coil device 1 includes a bobbin 20 having a winding core portion 21 around which a wire 41a is wound, a core 50a having a middle leg portion 53a inserted into the shaft hole of the winding core portion 21, and a case 90 housing the bobbin 20 to which the magnetic substance core 50a is attached. When the intermediate leg portion 53a is divided into an upper half ML1 and a lower half ML2 on an intermediate horizontal plane P0 passing through the midpoint O of a vertical distance line connecting the upper horizontal plane P1 including the upper end E1 of the intermediate leg portion 53a and the lower horizontal plane P2 including the lower end E2 of the intermediate leg portion 53a at the shortest distance, the intermediate leg portion 53a has a cross-sectional shape in which the cross-sectional area (CA2) of the lower half ML2 is larger than the cross-sectional area (CA1) of the upper half ML2.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to a coil device suitably used, for example, as a transformer or the like.

Background Art

[0002] As a coil device used for a relatively large transformer or the like, for example, a coil device shown in Patent Document 1 below has been developed. In this developed coil device, a bobbin around which a wire is wound is housed inside a case, and the inside of the case is filled with a resin having excellent heat transfer properties such as a potting resin, thereby enhancing heat dissipation.

[0003] However, in recent years, there has been a demand for a lower profile of coil devices such as transformers, and there has also been a demand for improving heat dissipation characteristics while reducing the size of the coil device.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In view of such a situation, the present invention has been made, and an object thereof is to provide a coil device that can be made lower profile and has excellent heat dissipation while reducing the size of the device.

Means for Solving the Problems

[0006] To achieve the above object, a coil device according to a first aspect of the present invention includes a bobbin having a winding core portion around which a wire is wound, a core having a middle leg portion inserted into the shaft hole of the winding core portion, a case that houses the bobbin to which the magnetic core is attached, A coil device having, When the middle leg is divided into an upper half and a lower half by an intermediate horizontal plane passing through the midpoint of the vertical distance line that connects the upper horizontal plane including the upper end of the middle leg and the lower horizontal plane including the lower end of the middle leg in the shortest possible distance, The middle leg portion has a cross-sectional shape such that the area of ​​the lower half of the cross-section (CA2) is larger than the area of ​​the upper half of the cross-section (CA1).

[0007] Furthermore, the coil device according to the second aspect of the present invention is A bobbin having a core around which the wire is wound, A core having a middle leg portion that is inserted into the axial hole of the aforementioned winding core portion, A case in which the bobbin to which the magnetic core is attached is housed, A coil device having, When the middle leg is divided into an upper half and a lower half by an intermediate horizontal plane passing through the midpoint of the vertical distance line that connects the upper horizontal plane including the upper end of the middle leg and the lower horizontal plane including the lower end of the middle leg in the shortest possible distance, The middle leg portion has a shape such that the volume of the lower half (V2) is larger than the volume of the upper half (V1).

[0008] Furthermore, the coil device according to the third aspect of the present invention is A bobbin having a core around which the wire is wound, A core having a middle leg portion that is inserted into the axial hole of the aforementioned winding core portion, A case in which the bobbin to which the magnetic core is attached is housed, A coil device having, When the middle leg is divided into an upper half and a lower half by an intermediate horizontal plane passing through the midpoint of the vertical distance line that connects the upper horizontal plane including the upper end of the middle leg and the lower horizontal plane including the lower end of the middle leg in the shortest possible distance, The middle leg portion has a shape such that the area of ​​the lower half of the outer surface (OA2) is larger than the area of ​​the upper half of the outer surface (OA1).

[0009] In the coil device according to the present invention (first to third aspects), the bobbin is arranged inside the case such that the wire winding axis is substantially parallel to the bottom surface of the case. In other words, the coil device of the present invention is a horizontal coil device, and it is possible to easily reduce its height compared to a vertical coil device in which the wire winding axis is substantially perpendicular to the bottom surface of the case.

[0010] Furthermore, by filling the inside of the case with a heat-dissipating resin such as potting resin, heat from the wire or bobbin (including the core) can be dissipated to the bottom of the case via the heat-dissipating resin, thereby improving heat dissipation.

[0011] Furthermore, in the coil device of the present invention, the area of ​​the lower half of the cross-sectional surface (CA2) is larger than the area of ​​the upper half of the middle leg portion of the core (CA1). Alternatively, the volume of the lower half (V2) is larger than the volume of the upper half of the middle leg portion of the core (V1). Alternatively, the area of ​​the outer circumferential surface of the lower half (OA2) is larger than the area of ​​the outer circumferential surface of the upper half of the middle leg portion of the core (OA1).

[0012] The coil device of the present invention has a core with a middle leg portion having such a relationship, making it possible to further reduce the height and size while improving heat dissipation compared to a coil device having a core with a normal middle leg shape (upper and lower halves are the same).

[0013] The case is filled with a heat-dissipating resin, such as potting resin, to cool the core and wire attached to the bobbin. However, the height of the case is restricted to the minimum necessary from the perspective of keeping the profile low. Therefore, the liquid level of the heat-dissipating resin contained inside the case must be lower than the upper horizontal plane including the upper end of the middle leg of the core. As a result, a portion of the upper end of the core, including the upper end of the middle leg, does not come into contact with the heat-dissipating resin.

[0014] In the coil device according to the present invention, due to the above-described configuration, the cross-sectional area, volume, and / or outer surface area of ​​the core in the portion that does not come into contact with the heat-dissipating resin can be minimized. Furthermore, the cross-sectional area, volume, and / or outer surface area of ​​the core in the portion that comes into contact with the heat-dissipating resin can be minimized. Therefore, the coil device according to the present invention makes it possible to further reduce the height and size while improving heat dissipation compared to a coil device having a core with a normal mid-leg shape (the upper and lower halves are the same).

[0015] The core may have a base portion to which the base end of the middle leg portion is connected, and outer leg portions connected to the base portion and positioned on both sides of the middle leg portion. That is, the core may have a so-called E-type core, or a combination of E-type cores, or a combination of E-type cores and I-type cores, or a combination of cores of other shapes. In any case, the core has at least a middle leg portion that is inserted into the axial hole of the winding core portion of the bobbin.

[0016] Preferably, the upper end of the outer leg portion and the upper end of the middle leg portion are at substantially the same height. This configuration improves the balance of magnetic flux and enhances the characteristics.

[0017] Preferably, the lower end of the middle leg portion is positioned above the lower end of the outer leg portion. As the wire is wound around the bobbin's core, a gap is formed for this purpose. Preferably, a notch is formed in the base portion located below the middle leg portion. Through the notch, a heat-dissipating resin such as potting resin can easily enter the axial center of the core near the bottom of the case, improving heat dissipation.

[0018] Preferably, when each of the outer leg portions is divided into an upper half and a lower half of the outer leg portion at the intermediate horizontal plane, the outer leg portion has a shape in which the volume (OV2) of the lower half of the outer leg portion is larger than the volume (OV1) of the upper half of the outer leg portion. Similar to the middle leg portion, by making the volume of the lower half of the outer leg portion larger than the volume of the upper half of the outer leg portion, it becomes possible to improve heat dissipation while reducing the height and size. Also, the balance of magnetic flux is improved and the characteristics are enhanced.

[0019] The case may be provided with a cover member that covers a part of the upper opening of the case with a predetermined gap. By covering a part of the upper opening of the case with the cover member, when connecting the terminals of the coil device to a substrate or the like, it is possible to effectively prevent the protruding portion from the substrate or the substrate itself from contacting and damaging the protruding portion of the core or the lead portion of the wire.

[0020] Preferably, the cover member covers at least a part of the wire wound around the bobbin housed inside the case. More preferably, the cover member covers the entire wound portion of the wire except for the lead portion of the wire. By forming the cover member of metal or the like, the effect of shielding the leakage magnetic flux from the wound portion (coil portion) of the wire is improved.

[0021] The cover member may be integrally formed with the case, or may be formed separately from the case and attached by fitting or the like. By integrally forming the cover member and the case by bending a metal plate or the like, the manufacture of the cover member and the case becomes easy. Also, the case may have a terminal block support portion that protrudes outward from the edge of the upper opening of the case.

[0022] Preferably, the terminal block support portion is integrally formed with the case. By integrally forming the terminal block support portion and the case by bending a metal plate or the like, the manufacture of the terminal block support portion and the case becomes easy.

[0023] Furthermore, the cover component can also function as a cooling mechanism. By giving the cover component a heat sink-like function, or by making the cover component come into contact with other cooling mechanisms, it is possible to dissipate heat from the heat-dissipating resin inside the case to the outside through the cover component.

[0024] The case may have a terminal block support portion that protrudes outward from the edge of the upper opening of the case. With this configuration, it is not necessary to increase the installation area of ​​the case in proportion to the area of ​​the terminal block, and the installation area of ​​the case can be reduced even though it is a horizontal type.

[0025] Furthermore, the terminal block may be placed on the terminal block support portion, or the terminal block support portion formed by extending the outer wall of the case may support the terminal block. By configuring it in this way, the strength and reliability of the terminal block can be improved. In particular, when connecting the terminals provided on the terminal block of the coil device to a circuit board placed on the coil device, the terminal block support portion reinforces the strength of the terminal block, making the connection to the circuit board easier and improving reliability.

[0026] Preferably, the terminal block has multiple terminals arranged substantially parallel to the winding shaft of the wire. This configuration makes it easy to arrange the terminals to which the lead portions of the multiple wires wound around the core of the bobbin are connected in a straight line in one or more rows along the opening edge of the case, and also facilitates the connection of each terminal to the circuit board.

[0027] Furthermore, in the coil device of the present invention, the terminal block may be mounted on the terminal block support portion via an insulating member. This configuration makes it easier to wind multiple wires onto a bobbin, attach multiple terminals to the terminal block, and then connect the lead portions of multiple wires to the terminals all at once. For example, heat sealing such as fusing can be used to connect the wire lead portions to the terminals.

[0028] When connecting the wire lead to the terminal, it is necessary to press a heat-sealing jig or similar tool against both sides of the lead. Before attaching the insulating member to the terminal block, it is easier to press the heat-sealing jig or similar tool against both sides of the lead. Furthermore, after connecting the wire lead to the terminal, the insulating member is positioned on one side of the joint between the terminal and the wire lead, thereby effectively ensuring insulation between that joint and the core attached to the bobbin. The insulating member can also ensure insulation between the lead and terminal joints and the case.

[0029] Preferably, the insulating member has an insulating sheet portion, which is positioned between the connection portion between the lead portion and the terminal of the wire and the outer leg portion of the core mounted on the bobbin. With this configuration, the insulating member can improve the insulation between the connection portion between the lead portion and the terminal and the outer leg portion of the core mounted on the bobbin. In addition, the insulating member can also improve the insulation between the connection portion of the lead portion and the terminal and the case.

[0030] Preferably, the insulating member further has an intermediate portion that is integrally molded with the insulating sheet portion and sandwiched between the terminal block support portion and the terminal block, and the intermediate portion has an intermediate engaging portion that engages with the terminal block. The intermediate engaging portion, such as an engaging claw, engages with the terminal block, making it easier to position and install the insulating member to the terminal block. Furthermore, it becomes possible to fix the insulating member to the terminal block without using adhesive. However, adhesive may be used.

[0031] Preferably, the intermediate portion has an intermediate protrusion that fits into a support through-hole formed in the terminal block support. The intermediate protrusion fitting into the support through-hole facilitates the positioning of the insulating member and the terminal block support.

[0032] The intermediate protrusion may have a receiving recess that opens toward the terminal block. The receiving recess may be configured so that a threaded portion for attaching the terminal to the terminal block fits into it. The receiving recess can accommodate metal debris and other waste generated when the threaded portion for attaching the terminal to the terminal block is screwed in.

[0033] The terminal block may have an engaging projection that engages with an engaging hole formed in the terminal block support through an intermediate through-hole formed in the intermediate portion. By engaging the engaging projection with the engaging hole formed in the terminal block support through the intermediate through-hole, the terminal block and the insulating member are positioned, and installation while positioning the terminal block and the terminal block support becomes easier. Furthermore, the terminal block, the insulating member, and the terminal block support can be fixed without using adhesive. However, adhesive may be used.

[0034] Preferably, the bobbin has a core portion around which the wire is wound, and a flange portion attached to the end of the core portion. Preferably, the flange portion has a protective hook portion that protrudes upward from the upper opening of the case and guides the wire lead to the terminal block. By hooking the wire lead onto the protective hook portion, it becomes easier to guide the wire lead portion to the terminal attached to the terminal block.

[0035] Preferably, the protective hook portion is at a height equal to or greater than the upper surface of the terminal, and the connection portion between the wire lead portion and the terminal is positioned lower than the upper surface of the terminal. By arranging them in this way, the protective hook portion protects the connection portion, effectively preventing protrusions from the substrate or the substrate itself from coming into contact with the connection portion.

[0036] Furthermore, preferably, the protective hook portion is lower than the lower surface of the cover member. By arranging them in this way, the cover member, together with the protective hook portion, protects the joint portion and effectively prevents protrusions from the substrate or the substrate itself from coming into contact with the joint portion.

[0037] Furthermore, the configuration of the terminal and terminal block is not limited to the above, and the terminal block may be attached to the flange of the bobbin. For example, terminal block engaging parts may be integrally formed on each flange located on both sides of the bobbin. Bobbin engaging parts (for example, arm parts) provided at both ends along the longitudinal direction of the terminal block may be fitted into these terminal block engaging parts (for example, engaging recesses), so that the terminal block can be attached to the bobbin in a snap-fit ​​manner.

[0038] This configuration makes it easy to arrange the terminals to which the leads of the multiple wires wound around the core of the bobbin are connected in a straight line in one or more rows along the opening edge of the case, and also facilitates the connection of each terminal to the circuit board.

[0039] Furthermore, terminal blocks can be arranged not only linearly along the X-axis on one side of the case's opening edge, but also divided and arranged on both sides along the Y-axis of the case. For example, a terminal block with two terminals can be placed on one side, and another terminal block with two terminals can be placed on the other side. [Brief explanation of the drawing]

[0040] [Figure 1A] Figure 1A is a schematic perspective view of a coil device according to one embodiment of the present invention. [Figure 1B] Figure 1B is a schematic perspective view of a coil device according to another embodiment of the present invention. [Figure 2] Figure 2 is an exploded perspective view of the coil device shown in Figure 1A. [Figure 3] Figure 3 is a side view of the coil device shown in Figure 1A. [Figure 4] Figure 4 is a schematic perspective view of the coil device shown in Figure 1A, taken from a diagonally downward direction. [Figure 5A] Figure 5A is a schematic perspective view of the bobbin portion of the coil device shown in Figure 1A. [Figure 5B] Figure 5B is a schematic perspective view of the bobbin portion shown in Figure 5A, viewed from a diagonally downward direction. [Figure 6A]Figure 6A is a schematic perspective view of the case of the coil device shown in Figure 1A. [Figure 6B] Figure 6B is a schematic perspective view of the case of the coil device shown in Figure 1B. [Figure 6C] Figure 6C is a schematic perspective view of the cover portion of the coil device shown in Figure 1B. [Figure 7] Figure 7 is a cross-sectional view of the core of the coil device shown in Figure 1A. [Figure 8] Figure 8 is a schematic perspective view of the terminal block of the coil device shown in Figure 1A. [Figure 9A] Figure 9A is an exploded perspective view of the terminal block and insulating member of the coil device shown in Figure 1A. [Figure 9B] Figure 9B is a schematic perspective view showing the assembled terminal block and insulation member shown in Figure 9A. [Figure 10] Figure 10 is a cross-sectional view of the coil device shown in Figure 1A along line XX. [Figure 11] Figure 11 is an exploded perspective view showing the relationship between the terminal block and the bobbin in a coil device according to another embodiment of the present invention. [Modes for carrying out the invention]

[0041] The present invention will be described below based on the embodiments shown in the drawings.

[0042] First Embodiment The coil device 10 shown in Figure 1A, as an example of the coil device according to this embodiment, functions as a transformer and is used in on-board chargers for EVs (Electric Vehicles), PHVs (Plug-in Hybrid Vehicles), or commuter vehicles, or in power supply circuits for household or industrial electrical equipment, or in power supply circuits for computer equipment, etc.

[0043] The detailed configuration of the coil device 10 will be described below. In the following description, the X, Y, and Z axes are perpendicular to each other in the drawings. The side of the coil device 10 that faces the center will be referred to as the inside or inward, and the side that moves away from the center of the coil device 10 will be referred to as the outside or outward.

[0044] As shown in Figure 2, the coil device 10 includes a bobbin 20, wires 41a and 41b, cores 50a and 50b, terminals 61a, 61b, 62a, and 62b, a terminal block 70, an insulating member 80, and a case 90. The coil device 10 is a horizontal coil device in which the winding axes C of the coil portions 42a and 42b of the wires 41a and 41b are arranged to be parallel to the bottom surface 90b of the case 90.

[0045] In this embodiment, the X-axis is parallel to the winding axis C of the wires 41a and 41b, and the Y-axis substantially coincides with the direction in which the lead portions 43a1, 43a2, 43b1, and 43b2 of the wires 41a and 41b are pulled out. The Z-axis corresponds to the height (thickness) direction of the coil device 10. In this embodiment, the upper part of the coil device 10 along the Z-axis is the mounting surface of the circuit board to which the terminals 61a, 61b, 62a, and 62b of the coil device 10 (transformer) are connected.

[0046] As shown in Figure 2, the coil portion 42a is formed by winding the wire 41a around the outer circumferential surface of the core portion 21 of the bobbin 20 shown in Figure 5A. The coil portion 42b is formed by winding the wire 41b around the outer circumferential surface of the core portion 21 of the bobbin 20 shown in Figure 5A. The wires 41a and 41b are wound around the outer circumferential surface of the core portion 21, for example, using an automatic winding machine.

[0047] As shown in Figure 10, the coil portion 42a (42b) formed by the wire 41a (41b) has one or more layers in the direction perpendicular to its winding axis (radial direction). As shown in Figure 2, the winding axes C of the coil portions 42a and 42b are approximately the same and are parallel to the X-axis.

[0048] As shown in Figure 2, coil section 42a is wound on one side along the X-axis of the core, and coil section 42b is wound on the other side along the X-axis of the core. Either coil section 42a or 42b constitutes the primary coil, and the other coil section 42a or 42b constitutes the secondary coil. The arrangement of the primary and secondary coils in the core can be either on one side or the other side along the X-axis of the core.

[0049] Wires 41a and 41b are each made of, for example, insulated wires, and are composed of conductors such as copper wires covered with an insulating layer. The conductors of wires 41a and 41b may each be made of single wires or twisted wires. The diameter of wires 41a and 41b is not particularly limited, and is, for example, 1.0 to 3.0 mm. The diameters of wires 41a and 41b may be equal or different. For example, the diameter of the wire carrying the large current may be thicker than the diameter of the other wire.

[0050] A lead portion 43a1 is formed at one end of wire 41a, and a lead portion 43a2 is formed at the other end of wire 41a. Similarly, a lead portion 43b1 is formed at one end of wire 41b, and a lead portion 43b2 is formed at the other end of wire 41b.

[0051] As shown in Figure 2, cores 50a and 50b are so-called E-shaped cores, and are attached to the bobbin 20. The materials of cores 50a and 50b include, but are not particularly limited to, metals and magnetic materials such as ferrite.

[0052] Cores 50a and 50b have the same shape (for example, E-type and E-type), but they may have different shapes (for example, E-type and I-type). In this embodiment, core 50a has a base portion 51a, a pair of outer legs 52a, and a middle leg portion 53a. Core 50b has a base portion 51b, a pair of outer legs 52b, and a middle leg portion 53b. The configuration of core 50a will be described below, but the description of core 50a also applies to core 50b. Therefore, unless particularly necessary, the description of the configuration of core 50b will be omitted.

[0053] The base portion 51a has a predetermined thickness along the X-axis and a predetermined length along the Y-axis and Z-axis, as shown in Figure 7. Hereinafter, as shown in Figure 2, the outer surface of the base portion 51a along the X-axis will be called the outer surface 510a, the inner surface along the X-axis will be called the inner surface 511a, the upper surface will be called the top surface 512a, and the lower surface will be called the bottom surface 513a. Similarly, the outer surface of the base portion 51b along the X-axis will be called the outer surface 510b, the inner surface along the X-axis will be called the inner surface 511b, the upper surface will be called the top surface 512b, and the lower surface will be called the bottom surface 513b.

[0054] The upper surface 512a and the lower surface 513a are surfaces perpendicular to the outer surface 510a and the inner surface 511a. The upper surface 512b and the lower surface 513b are surfaces perpendicular to the outer surface 510b and the inner surface 511b. As shown in Figure 7, the upper surface 512a of the base portion 51a is at the same height as the upper surface 522a of the outer leg portion 52a.

[0055] A recess (notch) 55a is formed on the lower surface 513a of the base portion 51a, recessing upward along the Z-axis at the position of the middle leg portion 53a. The recess 55a is formed approximately in the center of the base portion 51a with respect to the Y-axis and has a predetermined width along the X-axis and Y-axis. The width of the recess 55a along the Y-axis is smaller than the width of the middle leg portion 53a along the Y-axis and is approximately equal to the width of the concave bottom portion 37a or 37b of the bobbin 20 shown in Figure 5B along the Y-axis. The recess 55a shown in Figure 7 is formed to penetrate from the inner surface to the outer surface of the base portion 51a.

[0056] As shown in Figure 7, the recess 55a is recessed upward from the lower surface 513a to a predetermined depth. The upper end of the inner circumferential surface 550a of the recess 55a is located below the lower outer circumferential surface of the middle leg portion 53a, but it may be flush with the surface. In this embodiment, the inner circumferential surface 550a has a substantially flat ceiling surface, but it may be curved, triangular, or polygonal.

[0057] The inner circumferential surface 550a of the recess 55a may have tapered surfaces 551a on both sides along the Y-axis. The tapered surfaces 551a are formed such that the width of the recess 55a along the Y-axis narrows from the bottom surface 513a upwards. The shape of the recess 55a is substantially the same as the shape of the concave bottom 37a or 37b of the bobbin 20 shown in Figure 5B, but may be different.

[0058] As shown in Figure 2, the middle leg portion 53a is positioned between a pair of outer leg portions 52a and is connected to the inner surface 511a of the base portion 51a. The middle leg portion 53a extends from the inner surface 511a along the X-axis for a predetermined length and is positioned inside the through hole 211 of the bobbin 20. The middle leg portion 53a of the core 50a and the middle leg portion 53b of the core 50b are positioned inside the through hole 211 with their respective end faces 531a and 531b abutting against each other. A gap may be formed along the X-axis between the end face 531a of the middle leg portion 53a and the end face 531b of the middle leg portion 53b.

[0059] As shown in Figure 7, in this embodiment, the cross-section (cross-section perpendicular to the X-axis) of the middle leg portion 53a (53b) has a bulging shape at the bottom. That is, the middle leg portion 53a (53b) is divided into an upper half ML1 and a lower half ML2 by an intermediate horizontal plane P0 that passes through the midpoint of the vertical distance line connecting the upper horizontal plane P1 containing the upper end (along the Z-axis) E1 of the middle leg portion 53a (53b) and the lower horizontal plane P2 containing the lower end (along the Z-axis) E2 of the middle leg portion 53a (53b). The intermediate horizontal plane P0 is the plane containing the central axis (center along the Z-axis) O of the middle leg portion 53a (53b).

[0060] In this case, in the coil device 10 of this embodiment, the area of ​​the cross-sectional surface of the lower half ML2 of the middle leg portion 53a (53b) of the core 50a (50b) is larger than the area of ​​the cross-sectional surface of the upper half ML1 (CA1) (CA2). Alternatively, the volume of the lower half ML2 of the middle leg portion 53a (53b) of the core 50a (50b) is larger than the volume of the upper half ML1 (V1) (V2). Alternatively, the area of ​​the outer circumferential surface of the lower half ML2 of the middle leg portion 53a (53b) of the core 50a (50b) is larger than the area of ​​the outer circumferential surface of the upper half ML1 (OA1) (OA2).

[0061] In this embodiment, CA2 / CA1 is preferably 1.05 to 2.00, more preferably 1.09 to 1.50. Also, V2 / V1 is preferably 1.05 to 2.00, more preferably 1.09 to 1.50. Furthermore, OA2 / OA1 is preferably 1.30 to 2.00, more preferably 1.67 to 2.00. By setting the values ​​within this range, it is possible to reduce the height and size of the device 10 while improving the heat dissipation performance of the potting resin.

[0062] Furthermore, in this embodiment, the liquid level S of the potting resin, which will be described later, is lower by a predetermined height T1 than the upper end (along the Z-axis) E1 of the middle leg portion 53a (53b). This makes it possible to reduce the height of the coil device 10, including the case 90 shown in Figure 1A.

[0063] In this embodiment, T1 / T0 is preferably 0 to 1 / 3, and more preferably 1 / 5 to 1 / 3. By setting it within this range, it is possible to reduce the height of the device 10 while improving the heat dissipation by the potting resin. From the viewpoint of improving heat dissipation at the expense of reducing the height, the liquid level P1 of the potting resin may be above the upper end E1 of the middle leg portion 53a (53b).

[0064] Furthermore, in this embodiment, the Z-axis position of the upper end E1 of the outer circumferential surface of the middle leg portion 53a is preferably substantially the same as the Z-axis position with respect to the upper surface 512a of the base portion 51a, and the upper vertex of the middle leg portion 53a along the Z-axis is preferably connected to the upper surface 512a of the base portion 51a without any step. However, the Z-axis position of the upper end E1 of the outer circumferential surface of the middle leg portion 53a may be different from the Z-axis position with respect to the upper surface 512a of the base portion 51a. Also, the lower portion of the outer circumferential surface of the middle leg portion 53a, including the lower end E2, is preferably positioned close to the inner circumferential surface 550a of the recess 55a and above the inner circumferential surface 550a, but is not limited to this.

[0065] As shown in Figure 2, the pair of outer legs 52a are arranged at a predetermined interval along the Y-axis and are connected to the inner surface 511a of the base portion 51a. One of the pair of outer legs 52a is positioned at one end of the inner surface 511a along the Y-axis, and the other of the pair of outer legs 52a is positioned at the other end of the inner surface 511 along the Y-axis.

[0066] As shown in Figure 7, the inner surface 520a of the outer leg portion 52a curves inward along the Y-axis as it moves upward and downward from the intermediate horizontal plane P0 along the Z-axis of the outer leg portion 52a. Furthermore, the curved portion of the inner surface 520a of the outer leg is generally curved at predetermined intervals along the outer circumferential surface of the middle leg portion 53a. In addition, the curved portion of the inner surface 520a of the outer leg is generally curved along the outer circumferential edge of the flange portion 22a (flange portion body 220a) of the bobbin 20 shown in Figure 5A.

[0067] Furthermore, the outer surface of the outer leg portion 52a, which is located on the opposite side along the Y-axis from the inner surface 520a of the outer leg shown in Figure 7, has a plane perpendicular to the Y-axis and has a different shape from the curved shape of the inner surface 520a of the outer leg. In addition, a thickened portion 56a is formed at the lower end of each of the pair of outer leg portions 52a (52b) along the Z-axis, and is thicker in the Y-axis direction than the upper end of the outer leg portion 52a. The inner surface 520a (520b) of the thickened portion 56a protrudes inward along the Y-axis and is a plane perpendicular to the Y-axis.

[0068] In this embodiment, by forming a thickened portion 56a on the outer leg portion 52a, it is possible to secure a sufficient area of ​​the outer leg portion 52 covered by the potting resin, thereby obtaining a coil device 10 with good inductance characteristics.

[0069] Furthermore, in this embodiment, when each outer leg portion 52a (52b) is divided into an upper half OL1 and a lower half OL2 by an intermediate horizontal plane P0, the outer leg portion 52a (52b) has a shape such that the volume of the lower half OL2 is larger than the volume of the upper half OL1 (OV1).

[0070] Similar to the middle leg portion 53a (53b), the outer leg portion 52a (52b) can also be made smaller and more compact while improving heat dissipation by making the volume of the lower half of the outer leg OL2 larger than the volume of the upper half of the outer leg OL1. This also improves the balance of magnetic flux and enhances performance.

[0071] In this embodiment, OV2 / OV1 is preferably within the same range as V2 / V1 described above, and may be slightly larger or smaller than V2 / V1. Note that the volume of the outer leg portion may be replaced with the cross-sectional area or the area of ​​the outer surface of the outer leg portion, similar to the middle leg portion 53a (53b).

[0072] As shown in Figure 2, the pair of outer legs 52a, like the middle legs 53a, extend from the inner surface 511a along the X-axis for a predetermined length and are positioned outside the winding core 21 of the bobbin 20. The middle legs 53a are inserted into the through hole 211 of the bobbin 20.

[0073] As shown in Figures 5A and 5B, the bobbin 20 has a core portion 21 and flange portions 22a and 22b. The core portion 21 of the bobbin 20 extends along the X-axis, and flange portions 22a and 22b are formed at both ends of the core portion 21 along the X-axis. In the central part of the core portion 21 along the X-axis, projections 33 and 34 are formed on opposite sides of the Z-axis, respectively, projecting outward along the Z-axis.

[0074] The wires 41a and 41b shown in Figure 2 are wound around the outer surface of the core 21 to form coils 42a and 42b. Coil 42a is positioned between the flange 22a and the projection 33(34) on one side of the core 21 shown in Figure 5A along the X-axis. Coil 42b, shown in Figure 2, is positioned between the flange 22b and the projection 33(34) on the other side of the core 21 shown in Figure 5A along the X-axis.

[0075] As shown in Figure 2, one end of the coil portion 42a along the winding axis is positioned adjacent to the flange portion 22a, and the other end of the coil portion 42a along the winding axis is positioned adjacent to the protrusions 33 and 34. Similarly, one end of the coil portion 42b along the winding axis is positioned adjacent to the flange portion 22b, and the other end of the coil portion 42b along the winding axis is positioned adjacent to the protrusions 33 and 34.

[0076] As shown in Figure 5B, the core portion 21 is cylindrical, and the through hole 211 of the core portion 21 is horizontal The cross-section has a downward-bulging shape corresponding to the cross-section of the middle leg portion 53a shown in Figure 7. The axis of the winding core portion 21 is parallel to the X-axis. The middle leg portions 53a and 53b of the cores 50a and 50b can be housed inside the through hole 211 while creating a predetermined gap (which may be partially zero) on their outer surface.

[0077] As shown in Figure 5A, a through hole 35 is formed in the upper part of the outer circumferential surface of the winding core 21, penetrating both the inside and outside of the winding core 21. The through hole 35 is located approximately in the center of the winding core 21 with respect to the X and Y axes, and is situated between the protruding portions 33, 33. The through hole 35 has a substantially elliptical opening with a long diameter along the X axis. The cross-sectional shape of the through hole 35 corresponds to the cross-sectional shape of the intermediate leg portions 53a and 53b, allowing the intermediate leg portions 53a and 53b to be inserted into the through hole 35 with a predetermined gap.

[0078] As shown in Figure 5B, a through-hole 36 is also formed in the lower part of the outer circumferential surface of the core 21, penetrating both the inside and outside of the core 21. The through-hole 36 is located approximately in the center of the core 21 with respect to the X and Y axes, and is situated between the protruding portions 34, 34. The through-hole 36 has a substantially elliptical opening with a longer diameter along the X axis. Along the Z axis, the through-hole 36 is formed opposite to the through-hole 35.

[0079] By forming through holes 35 and 36 in the core portion 21, the potting resin 210 (see Figure 10) can be circulated through these through holes 35 and 36 to the inside and outside of the bobbin 20 (core portion 21), allowing the potting resin 210 to reach every corner of the case 90.

[0080] As shown in Figure 5A, the flange portion 22a is formed at one end of the winding core portion 21 along its axis, and the flange portion 22b is formed at the other end of the winding core portion 21 along its axis. The flange portions 22a and 22b have the same shape, but may be different. The flange portion 22a has a flange body 220a at one end of the winding core portion 21 along its X axis, extending circumferentially along the outer surface of the winding core portion 21. The flange portion 22b has a flange body 220b at the other end of the winding core portion 21 along its Y axis, extending circumferentially along the outer surface of the winding core portion 21.

[0081] The flange body 220a is made of a plate having a predetermined thickness along the X-axis and protrudes outward along the radial direction of the winding core 21. The flange body 220b is made of a plate having a predetermined thickness along the X-axis and protrudes outward along the radial direction of the winding core 21.

[0082] As shown in Figure 5B, a pair of mounting portions 32a are formed below the flange body 220a so as to protrude downward from the body 220a along the Z-axis. One mounting portion 32a is formed on one side of the flange body 220a along the Y-axis, and the other mounting portion 32a is formed on the other side of the flange body 220a along the Y-axis. The two mounting portions 32a are arranged at a predetermined interval along the Y-axis. The pair of mounting portions 32a extend substantially parallel to the flange body 220a along the YZ plane, and the bottom surfaces of the pair of mounting portions 32a are substantially flat surfaces flush with the surface. The pair of mounting portions 32a are placed on the bottom surface 90b of the case 90 shown in Figure 2.

[0083] As shown in Figure 5B, below the flange body 220b, a pair of mounting sections 32b are formed, similar to the pair of mounting sections 32a. The configuration and function of the pair of mounting sections 32b are the same as those of the pair of mounting sections 32a, so a detailed explanation is omitted. The winding core 21 of the bobbin 20 can be supported via the pair of mounting sections 32a and the pair of mounting sections 32b.

[0084] A concave bottom portion 37a is formed between each of the pair of mounting portions 32a, and the pair of mounting portions 3 A concave bottom portion 37b is formed between each of the 2b. The concave bottom portions 37a and 37b have a shape that is recessed upward from the position of the bottom surface of the mounting portion 32a and 32b. Tapered inclined portions are formed on both sides of the inner circumferential surface of the concave bottom portions 37a and 37b.

[0085] The inner circumferential surface shapes of the concave bottom portions 37a and 37b correspond to the inner circumferential surface shapes of the recesses 55a (55b) formed in the core 50a (50b) shown in Figure 7, and are preferably substantially the same shape, but may be larger or smaller. As shown in Figure 5B, the upper ends of the concave bottom portions 37a and 37b may be at the same height as the lower end of the outer circumferential surface of the winding core portion 21, but may also be lower.

[0086] By forming concave bottoms 37a and 37b on the flange bodies 220a and 220b, the concave bottoms 37a and 37b function as flow channels for the potting resin 210 (Figure 10) during filling. For example, the potting resin 210 flows through the interior of the concave bottoms 37a (37b) from the inside (outside) to the outside (inside) along the X-axis of the concave bottoms 37a (37b), allowing the potting resin 310 to spread particularly to the lower part of the bobbin 20.

[0087] From the viewpoint of improving heat dissipation by improving the flow of potting resin in the X-axis direction, it is preferable for the size of the concave bottom portions 37a and 37b to be as large as possible, but this is determined by balancing it with the strength of the mounting portions 32a and 32b. The same applies to the recesses 55a (55b) formed in the core 50a (50b) shown in Figure 7.

[0088] As shown in Figure 5A, protective hook portions 23a and 24a are formed above the flange body 220a, aligned along the Y-axis. The protective hook portions 23a and 24a are connected to the upper part of the flange body 220a via protective hook holding portions 23a1 and 24a1. Core separation walls 25a and 26a are formed on the protective hook holding portions 23a1 and 24a1. The core separation walls 25a and 26a protrude outward along the X-axis and face the protective hook portions 23a and 24a.

[0089] An extended flange portion 27a is formed above the main flange portion 220a. The extended flange portion 27a is integrally connected to the upper part of the main flange portion 220a and extends substantially parallel to the main flange portion 220a along the YZ plane. That is, the extended flange portion 27a has a shape that is an extension of the main flange portion 220a upward and constitutes a part of the main flange portion 220a. The extended flange portion 27a has a predetermined thickness along the X axis and a surface substantially parallel to the YZ plane.

[0090] A notch 28a is formed between each protective hook portion 23a and 24a. The lead portions 43a1 and 43a2 of the wire 41a shown in Figure 2 can be inserted through the notch 28a. Additionally, the lead portion 43a1 shown in Figure 2 can be inserted between the core separation wall 25a and the protective hook portion 23a. Furthermore, the lead portion 43a2 can be inserted between the core separation wall 26a and the protective hook portion 24a.

[0091] In this embodiment, as shown in Figure 2, of the lead portions 43a1 and 43a2, lead portion 43a1 is inserted through the notch 28a shown in Figure 5A, passes between the core separation wall 25a and the protective hook portion 23a, and is drawn out toward terminal 61a. Similarly, lead portion 43a2 shown in Figure 2 is inserted through the notch 28a, passes between the core separation wall 26a and the protective hook portion 24a, goes around the outside of the protective hook portion 24a along the Y axis, and is drawn out toward terminal 62a. The core separation walls 25a and 26a ensure good insulation between the lead portions 43a1 and 43a2 and the core 50a.

[0092] As shown in Figure 5A, above the flange body 220b, there are protective hooks arranged along the Y-axis. Sections 23b and 24b are formed. The protective hook sections 23b and 24b are connected to the upper part of the flange body 220b via protective hook holding sections 23b1 and 24b1. Core separation walls 25b and 26b are formed on the protective hook holding sections 23b1 and 24b1. The core separation walls 25b and 26b protrude outward along the X-axis and face the protective hook sections 23b and 24b.

[0093] An extended flange portion 27b is formed above the main flange portion 220b. The extended flange portion 27b is integrally connected to the upper part of the main flange portion 220b and extends substantially parallel to the main flange portion 220b along the YZ plane. That is, the extended flange portion 27b has a shape that is an extension of the main flange portion 220b upward and constitutes a part of the main flange portion 220b. The extended flange portion 27b has a predetermined thickness along the X axis and a surface substantially parallel to the YZ plane.

[0094] A notch 28b is formed between each protective hook portion 23b and 24b. The lead portions 43b1 and 43b2 of the wire 41b (Figure 2) can be inserted through the notch 28b. Additionally, the lead portion 43b1 can be inserted between the core separation wall 25b and the protective hook portion 23b. Furthermore, the lead portion 43b2 can be inserted between the core separation wall 26b and the protective hook portion 24b.

[0095] In this embodiment, as shown in Figure 2, of the lead portions 43b1 and 43b2, lead portion 43b1 is inserted through the notch 28b, passes between the core separation wall 25b and the protective hook portion 23b, and is drawn out toward terminal 61b. Similarly, lead 43b2 is inserted through the notch 28b, passes between the core separation wall 26b and the protective hook portion 24b, wraps around the outside along the Y-axis of the protective hook portion 24b, and is drawn out toward terminal 62b. The core separation walls 25b and 26b ensure good insulation between the lead portions 43b1 and 43b2 and the core 50b.

[0096] As shown in Figure 6A, the case 90 is constructed by bending a single plate-shaped member made of a metal with excellent cooling properties, such as aluminum. The case 90 is composed of a plate-shaped member that forms the lower bottom surface 90b along the Z axis, plate-shaped members that form the side surfaces 90c, 90c on both sides along the X axis, and plate-shaped members that form the side surfaces 90d, 90d on both sides along the Y axis, with the upper side having an upper opening 90a along the Z axis. There are gaps between the plate-shaped members on the side surfaces 90c, and there are also gaps between the plate-shaped members between the side surfaces 90c and the bottom surface 90b.

[0097] The case 90 has a terminal block support portion 91. The terminal block support portion 91 is positioned on the upper side along the Z axis of one side surface 90d along the Y axis and protrudes outward along the X axis from the opening edge 96 of the upper opening 90a. The terminal block support portion 91 has support through holes 92a, 92b, 93a, 93b, engagement holes 94a, 94b, and a central hole 95.

[0098] The case 90 is further molded integrally with the cover member 100. The side cover portion 102 of the cover member 100 is connected to the other side surface 90d of the case 90 along the Y axis. The opening cover portion 101 of the cover member 100 is connected to the side cover portion 102 and covers a portion of the upper opening 90a along the Z axis.

[0099] As shown in Figure 2, the terminal block 70 is formed separately from the bobbin 20 and is attached to the upper side of the terminal block support 91 along the Z-axis via an insulating member 80. The terminal block 70 may be made of the same insulating material as the bobbin 20, but it is preferable to make it of an insulating material with better moldability (or heat resistance or insulating properties). The insulating member 80 may also be made of the same insulating material as the bobbin 20, but it is preferable to make it of an insulating material with better insulating properties. The bobbin 20 is made of plastic such as PPS, PET, PBT, LCP, or other insulating material (preferably a heat-resistant material).

[0100] As shown in Figure 8, the terminal block 70 has a terminal block base portion 701 that extends along the X-axis. Fastener placement holes 71a, 71b, 72a, and 72b are formed in the terminal block base portion 701 along the X-axis. Fasteners 78a, 78b, 79a, and 79b can be embedded in the fastener placement holes 71a, 71b, 72a, and 72b, respectively.

[0101] The fasteners 78a, 78b, 79a, and 79b may be integrally molded with the terminal block base portion 701. Bolts or the like for fixing external terminals from a circuit board or the like can be detachably attached to each of the fasteners 78a, 78b, 79a, and 79b. The fastener placement holes 71a, 71b, 72a, and 72b penetrate the terminal block base portion 701 from the upper surface along the Z-axis to the lower side along the Z-axis.

[0102] In this embodiment, the fasteners 78a, 78b, 79a, and 79b are, for example, hexagonal nuts and have a hexagonal outer shape corresponding to the fastener placement holes 71a, 71b, 72a, and 72b. Around each of the fastener placement holes 71a, 71b, 72a, and 72b, mounting claw holes 73a1 to 73a4, 73b1 to 73b4, 74a1 to 74a4, and 74b1 to 74b4 are formed along the Z-axis of the terminal block base portion 701, extending downward along the Z-axis from the upper surface. The terminals and the terminal block 70 can be fixed by inserting the mounting claws of the terminals, which will be described later, into the mounting claw holes 73a1 to 73a4, 73b1 to 73b4, 74a1 to 74a4, and 74b1 to 74b4.

[0103] As shown in Figure 9A, in this embodiment, a terminal separation wall fitting groove 77 is formed on the inner surface of the terminal block base portion 701 along the Y-axis, and along the Z-axis. The terminal separation wall fitting groove 77 is formed so that the terminal separation wall 87 fits into it. In addition, an engagement notch 76 is formed on the outer surface of the terminal block base portion 701 along the Y-axis, midway between the fastener placement holes 72a and 72b. The engagement claw 861 of the intermediate engagement portion 86 of the insulating securing member 80 catches on the engagement notch 76, thereby fixing the terminal block 70 and the insulating securing member 80.

[0104] As shown in Figure 9A, engaging projections 75a and 75b are formed on the lower surface of the terminal block base portion 701 of the terminal block 70 along the Z-axis. The engaging projections 75a and 75b extend downward along the Z-axis. The engaging projections 75a and 75b are formed at positions corresponding to the intermediate through holes 85a and 85b of the insulating securing member 80 shown in Figure 9B and the support through holes 94a and 94b of the terminal block support portion 91 shown in Figure 6A.

[0105] The engaging protrusions 75a and 75b are inserted through the intermediate through holes 85a and 85b of the insulating member 80 shown in Figure 9B and the support through holes 94a and 94b of the terminal block support part 91 shown in Figure 6A, and as shown in Figure 4B, they hook onto the lower surface of the terminal block support part 91 along the Z axis. In this way, the terminal block 70, the insulating member 80, and the terminal block support part 91 can be fixed together.

[0106] As shown in Figure 2, the insulating member 80 has an intermediate portion 82 positioned between the terminal block 70 and the terminal block support portion 91, and an insulating sheet portion 81 positioned between the outer leg portions 52a, 52b of the cores 50a, 50b and the terminals 61a, 61b, 62a, 62b. The intermediate portion 82 and the insulating sheet portion 81 are integrally molded into a thin sheet along a plane perpendicular to the Z-axis. The intermediate portion 82 is connected to the outside of the insulating sheet portion 81 along the Y-axis.

[0107] As shown in Figure 9A, a terminal separation wall 87 is formed in the middle portion of the insulating member 80 along the X-axis, extending upward along the Z-axis. As shown in Figure 1A, the terminal separation wall 87 is positioned between terminals 62a and 62b, ensuring insulation between terminals 62a and 62b, where the voltage difference tends to be large.

[0108] As described above, intermediate through holes 85a and 85b are formed in the intermediate portion 82 of the insulating member 80 shown in Figure 9A, through which the engaging protrusions 75a and 75b of the terminal block 70 can be inserted. Also, as described above, an intermediate engaging portion 86 is formed in the intermediate portion 82 at a position corresponding to the engaging notch 76 of the terminal block 70.

[0109] Although not shown in Figure 9A, as shown in Figure 9B, a central projection 88 is integrally formed on the lower surface of the intermediate portion 82, protruding downward along the Z-axis and positioned centrally along the X-axis. As shown in Figure 4, the central projection 88 of the insulating member 80 is inserted through the central hole 95 of the terminal block support portion 91, thereby positioning the insulating member 80 and the case 90.

[0110] As shown in Figure 9B, intermediate protrusions 83a, 83b, 84a, and 84b are formed in the intermediate portion 82 of the insulating member 80. Each of the intermediate protrusions 83a, 83a, 84a, and 84b protrudes downward along the Z-axis. Each of the intermediate protrusions 83a, 83b, 84a, and 84b corresponds to the positions of the support through holes 92a, 92b, 93a, and 93b of the terminal block support portion 91 shown in Figure 4, and is formed in a line along the X-axis.

[0111] The intermediate protrusions 83a, 83a, 84a, and 84b of the insulating member 80 shown in Figure 9B may be inserted into the support through holes 92a, 92b, 93a, and 93b shown in Figure 6A to align the insulating member 80 with the terminal block support 91.

[0112] As shown in Figure 9B, fixing protrusions 83a2 and 83b2 may be formed on the outer circumferential surface of the intermediate protrusions 83a and 83b, with the outer diameter decreasing towards the lower end along the Z-axis. Forming such intermediate protrusions 83a and 83b makes it easier to position and insert the intermediate protrusions 83a, 83a, 84a, and 84b of the insulating member 80 into the corresponding support through holes 92a, 92b, 93a, and 93b. Furthermore, the connection between them becomes stronger.

[0113] As shown in Figure 9A, the intermediate protrusions 83a, 83a, 84a, and 84b each have receiving recesses 83a1, 83b1, 84a1, and 84b1 formed therein, which are recessed downwards along the Z-axis and open upwards. The receiving recesses 83a1, 83b1, 84a1, and 84b1 correspond to the positions of the fastener placement holes 71a, 71b, 72a, and 72b of the terminal block 70.

[0114] Each of the recesses 83a1, 83b1, 84a1, and 84b1 is configured to accommodate the threaded portion of a bolt used to connect an external terminal, such as a circuit board (not shown), to the terminals 61a, 61b, 62a, and 62b of the terminal block 70. In addition, each of the recesses 83a1, 83b1, 84a1, and 84b1 can also accommodate metal debris generated when screwing the bolts (not shown) to the fasteners 78a, 78b, 79a, and 79b.

[0115] As shown in Figure 1A, terminal 61a has a main terminal portion 63a and a connecting portion 63a. Similarly, terminal 61b has a main terminal portion 63b and a connecting portion 63b. Terminal 62a has a main terminal portion 64a and a connecting portion 64a. Similarly, terminal 62b has a main terminal portion 64b and a connecting portion 64b. The configuration of terminal 61a will be described below, but the description of terminal 61a also applies to terminals 61b, 62a, and 62b. Therefore, unless specifically necessary, the descriptions of the configurations of terminals 61b, 62a, and 62b will be omitted.

[0116] As shown in Figure 1A, the main terminal portion 63a is placed on the upper surface of the terminal block base portion 701 along the Z-axis. The main terminal portion 63a of terminal 61a has a connection hole 65a and mounting claws 63a1 to 63a4 formed therein. The connection hole 65a is positioned to correspond to the fasteners 78a, 78b, 79a, and 79b shown in Figure 9A. The terminal 61a is fixed to the terminal block 70 by inserting the mounting claws 63a1 to 63a4 shown in Figure 1A or Figure 2 into the mounting claw holes 73a1 to 73a4 shown in Figure 9A.

[0117] The main terminal portion 63a shown in Figure 1A is connected to the connecting portion 67a on the inside along the Y-axis. The connecting portion 67a has a folded-back piece 67a1 that can be used to clamp and secure the lead portion. As shown in Figure 3, the connecting portion 67a is positioned lower by h2 along the Z-axis than the main terminal portion 63a. Also, the connecting portion 67a is positioned higher along the Z-axis than the insulating sheet portion 81.

[0118] As shown in Figure 1A, terminals 61a, 61b, 62a, and 62b are attached to the terminal block 70 at predetermined intervals along the X-axis to the terminal fixing parts 71a1, 71b1, 72a1, and 72b1 shown in Figure 9A.

[0119] In this embodiment, as shown in Figure 1A, terminal 61a is connected to lead portion 43a1, terminal 61b is connected to lead portion 43b1, terminal 62a is connected to lead portion 43a2, and terminal 62b is connected to lead portion 43b2.

[0120] The coil device 10 of this embodiment can be assembled, for example, as follows.

[0121] First, as shown in Figure 2, wires 41a and 41b are wound onto the core portion 21 of the bobbin 20, for example, using an automatic winding machine. Before or after this, or simultaneously, the mounting claws 63a1 to 63a4 (63b1 to 63b4, 64a1 to 64a4, 64b1 to 64b4) of terminals 61a (61b, 62a, 62b) are inserted into the mounting claw holes 73a1 to 73a4 (73b1 to 73b4, 74a1 to 74a4, 74b1 to 74b4), and terminals 61a (61b, 62a, 62b) are attached to the terminal block 70.

[0122] Next, the lead portion 43a1 (43a2, 43b1, 43b2) is temporarily fixed between the connecting portion 67a (67b, 68a, 68b) of terminal 61a (61b, 62a, 62b) and the folded portion 67a1 (67b1, 68a1, 68b1). Then, the connecting portion 67a (67b, 68a, 68b) is pressed from above along the Z-axis with electrodes, and the folded portion 67a1 (67b1, 68a1, 68b1) is pressed from below along the Z-axis with other electrodes. By applying a voltage between the electrodes, the terminal 61a (61b, 62a, 62b) and the lead portion 43a1 (43a2, 43b1, 43b2) are electrically and mechanically connected by fusing.

[0123] In this embodiment, during fusing, there are no components above or below the joint portion 67a(67b,68a,68b) along the Z-axis, and electrodes can press down on the joint portion 67a(67b,68a,68b) and the folded piece 67a1(67b1,68a1,68b1) from above and below.

[0124] Next, the insulating member 80 is attached to the terminal block 70. Before that, the fasteners 78a, 78b, 79a, and 79b are attached to the terminal block 70. When attaching the insulating member 80 to the terminal block 70, as shown in Figure 9A, the engaging claws 861 of the intermediate engaging portion 86 are engaged with the engaging notches 76, and the terminal separation wall 87 is fitted into the terminal separation wall fitting groove 77.

[0125] Next, as shown in Figure 2, the middle legs 53a and 53b of the cores 50a and 50b are inserted into the through-hole 21 of the bobbin 20, and the bobbin 20 and the cores 50a and 50b are fixed together, for example, with an adhesive. A thermosetting adhesive can preferably be used.

[0126] Next, the bobbin 20, which has the cores 50a and 50b assembled, is placed in the case 90, which has been pre-filled with potting resin (a resin with excellent heat dissipation properties) 210. At this time, as shown in Figure 4, the insulating member 80 to which the terminal block 70 is attached is attached to the terminal block support part 91. Alternatively, the potting resin may be injected through the opening 90a after the bobbin 20 and cores 50a and 50b have been placed in the case 90.

[0127] When attaching the insulating member 80, to which the terminal block 70 is attached, to the terminal block support 91, the intermediate protrusions 83a (83b, 84a, 84b) are inserted into the support through holes 92a (92b, 93a, 93b). The central protrusion 88 is inserted through the central hole 95. The engaging protrusions 75a and 75b are inserted through the intermediate through holes 85a and 85b, and the claws formed on the engaging protrusions 75a and 75b engage with the terminal block support 91. In this way, the terminal block 70 and the insulating member 80 are fixed to the terminal block support 91.

[0128] After placing the bobbin 20 into the case 90, the cover member 100 of the case 90 is bent as shown in Figure 2 to form the opening cover portion 101 shown in Figure 1A. By forming the opening cover portion 101 in this way, it is not necessary to form and attach the cover member 100 separately from the case 90, making assembly easier.

[0129] In this embodiment, as shown in Figure 2, the bobbin 20 is positioned inside the case 90 such that the winding axis C of the wires 41a and 41b is substantially parallel to the bottom surface 90b of the case 90. In other words, the coil device 10 of this embodiment is a horizontal coil device and is substantially parallel to the mounting surface of the coil device 10 or the mounting surface of the mounting substrate (not shown). This coil device 10 can be made lower in profile more easily than a vertical coil device in which the winding axis of the wires 41a and 41b is substantially perpendicular to the bottom surface 90b of the case 90.

[0130] Furthermore, as shown in Figure 1A, in the coil device 10 of this embodiment, the terminal block 70 is supported on a terminal block support portion 91 that protrudes outward along the Y-axis from the opening edge 96 of the upper opening 90a of the case 90. Therefore, it is not necessary to increase the installation area of ​​the case 90 in proportion to the area of ​​the terminal block 70, and the installation area of ​​the case 90 can be reduced despite being a horizontal type. Moreover, it is possible to reduce the installation area of ​​the case along the X-axis compared to the case in which terminal blocks are provided on both sides along the X-axis.

[0131] Furthermore, since the terminal block support portion 91, which is formed by extending the outer wall of the case 90, supports the terminal block 70, the strength and reliability of the terminal block 70 can be improved. In particular, when connecting the terminals 61a, 61b, 62a, and 62b provided on the terminal block 70 of the coil device 10 to a substrate (not shown) placed on the coil device 10, the terminal block support portion 91 reinforces the strength of the terminal block 70, making the connection to the substrate easier and improving reliability.

[0132] Furthermore, in this embodiment, as shown in Figure 2, the terminal block 70 has multiple terminals 61a, 62a, 61b, and 62b arranged substantially parallel to the winding shafts C of the wires 41a and 41b. This configuration makes it easy to arrange the terminals 61a, 62a, 61b, and 62b to which the lead portions 43a1, 43a2, 43b1, and 43b2 are connected in a straight line in one or more rows along the opening edge 96 of the case 90, and also facilitates the connection of each terminal to the circuit board.

[0133] Furthermore, as shown in Figure 10, by filling the inside of the case 90 with a heat-dissipating resin (potting resin 210), heat from the wires 42, 44 or bobbins 20 (including cores 50a, 50b) can be dissipated to the bottom of the case 90 via the potting resin 210, thereby improving heat dissipation. A cooling mechanism is located on the bottom of the case 90.

[0134] Furthermore, as shown in Figure 1A, the terminal block 70 is supported on a terminal block support portion 91 that protrudes outward from the opening edge 96 of the upper opening 90a of the case 90, so the terminal block 70 does not get in the way, and the bobbin 20 (including the winding shafts of at least the wires 41a and 41b) is supported. The majority of the core (including the core) is brought into contact with the potting resin 210 inside the case 90. This allows for effective heat dissipation using the minimum necessary amount of potting resin.

[0135] In this embodiment, as shown in Figure 6A, position adjustment portions 97a and 97b may be formed on the side surface 90d of the case 90. As shown in Figure 10, the position adjustment portions 97a (97b) protrude inward along the Y-axis inside the case 90.

[0136] When the bobbin 20 and cores 50a and 50b are housed in the case 90, the elastic force of the wire leads may cause them to be pressed against the side surface 90d of the case 90, which is on the opposite side of the terminal block 70 along the Y-axis. The position adjustment parts 97a (97b) come into contact with the outer legs 52a (52b) of the cores 50a (50b), creating a gap between the side surface 90d and the cores 50a into which the potting resin 210 can be inserted.

[0137] Furthermore, as shown in Figure 1A, in the coil device 10 of this embodiment, the terminal block 70 is mounted on the terminal block support 91 via an insulating member 80. This makes it easy to wind the wires 41a and 41b onto the bobbin 20 and attach the terminals 61a, 61b, 62a, and 62b to the terminal block 70, and then connect the lead portions 43a1, 43a2, 43b1, and 43b2 of the wires 41a and 41b to the terminals 61a, 61b, 62a, and 62b all at once. The connection of the lead portions 43a1, 43a2, 43b1, and 43b2 of the wires 41a and 41b to the terminals 61a, 61b, 62a, and 62b can be appropriately performed using, for example, thermocompression bonding such as fusing.

[0138] When connecting the lead portions 43a1, 43a2, 43b1, and 43b2 of the wires 41a and 41b to terminals 61a, 61b, 62a, and 62b, it is necessary to press a heat-sealing jig or the like from both sides of the lead portions 43a1, 43a2, 43b1, and 43b2. In this embodiment, as described above, it is easy to press a heat-sealing jig or the like from both sides of the lead portions 43a1, 43a2, 43b1, and 43b2 before attaching the insulating member 80 to the terminal block 70.

[0139] Furthermore, after the connection of the lead portions 43a1, 43a2, 43b1, and 43b2 of the wires 41a and 41b to the terminals 61a, 61b, 62a, and 62b, the insulating member 80 is placed on one side of the connecting portions 67a, 67b, 68a, and 68b of the wires 41a and 41b. This effectively ensures insulation between the connecting portions 67a, 67b, 68a, and 68b and the cores 50a and 50b attached to the bobbin 20.

[0140] Furthermore, the insulating member 80 can also ensure insulation between the lead portions 43a1, 43a2, 43b1, 43b2 and the connecting portions 67a, 67b, 68a, 68b of the terminals 61a, 61b, 62a, 62b and the case 90.

[0141] As shown in Figure 3, in this embodiment, the insulating member 80 has an insulating sheet portion 81. The insulating sheet portion 81 is positioned between the connecting portions 67a, 67b, 68a, 68b between the lead portions 43a1, 43a2, 43b1, 43b2 of the wires 41a, 41b and the terminals 61a, 61b, 62a, 62b, and the cores 50a, 50b that are mounted on the bobbin 20.

[0142] With this configuration, the insulating member 80 can improve the insulation between the connecting parts 62b, 63b, 65b, 66 of the lead sections 43a1, 43a2, 43b1, 43b2 and terminals 61a, 61b, 62a, 62b and the outer legs 52a, 52b of the cores 50a, 50b mounted on the bobbin 20. In addition, the insulating member 80 can also improve the insulation between the connecting parts 67a, 67b, 68a, 68b of the lead sections 43a1, 43a2, 43b1, 43b2 and terminals 61a, 61b, 62a, 62b and the case 90.

[0143] As shown in Figure 3, in this embodiment, the insulating member 80 has an intermediate portion 82 integrally molded with the insulating sheet portion 81. The intermediate portion 82 is sandwiched between the terminal block support portion 91 and the terminal block 70. As shown in Figure 9A, the insulating member 80 has an intermediate engaging portion 86 that engages with the terminal block 70, and the intermediate engaging portion 86 has an engaging claw 861. The engagement of the intermediate engaging portion 86 with the terminal block 70 facilitates the positioning and installation of the terminal block 70 and the insulating member 80. Furthermore, it becomes possible to fix the terminal block 70 and the insulating member 80 without using adhesive. However, adhesive may be used.

[0144] As shown in Figure 4, in this embodiment, the intermediate portion 82 has intermediate protrusions 83a, 83b, 84a, 84b that fit into the support through holes 92a, 92b, 93a, 93b formed in the terminal block support portion 91. The intermediate protrusions 83a, 83b, 84a, 84b fit into the support through holes 92a, 92b, 93a, 93b, which facilitates the positioning of the insulating member 80 and the terminal block support portion 91.

[0145] As shown in Figure 9A, the intermediate protrusions 83a, 83b, 84a, and 84b have receiving recesses 83a1, 83b1, 84a1, and 84b1 that open toward the terminal block 70. The receiving recesses 83a1, 83b1, 84a1, and 84b1 can accommodate metal debris and other debris that occurs when the screw threads connect the terminals 61a, 61b, 62a, and 62b to the circuit board and other components mechanically and electrically. The receiving recesses 83a1, 83b1, 84a1, and 84b1 are configured to accommodate screw threads for attaching external terminals of a circuit board (not shown) to the terminals 61a, 61b, 62a, and 62b of the terminal block.

[0146] As shown in Figure 4, the terminal block 70 has engaging protrusions 75a and 75b. Also, as shown in Figure 9A, intermediate through holes 85a and 85b are formed in the intermediate portion 82 of the insulating member 80. As shown in Figure 4, the engaging protrusions 75a and 75b engage with the engaging holes 94a and 94b formed in the terminal block support portion 91 through the intermediate through holes in the intermediate portion.

[0147] This configuration allows for precise positioning of the terminal block 70 and the insulating member 80, and facilitates the installation of the terminal block 70 and the terminal block support 91 while maintaining their position. Furthermore, it becomes possible to fix the terminal block 70, the insulating member 80, and the terminal block 70 support without using adhesive. However, adhesive may be used.

[0148] As shown in Figure 1A, the case 90 is equipped with a cover member 100. The opening cover portion 101 of the cover member 100 covers at least a portion of the upper opening 90a of the case 90 with a predetermined gap H1 as shown in Figure 3. The predetermined gap H1 is greater than the protrusion height of the bobbin 20's protrusion portion 33 from the upper opening 90a of the case 90, and greater than the protrusion height of the protective hook portions 23a, 23b, 24a, and 24b.

[0149] The opening cover portion 101 covers a portion of the upper opening 90a of the case 90 with a predetermined gap H1, thereby protecting the protrusions of the cores 50a and 50b and the lead portions 43a1, 43a2, 43b1, and 43b2 of the wires 41a and 41b. For example, when connecting the terminals 61a, 61b, 62a, and 62b of the coil device 10 to a substrate, it is possible to effectively prevent damage to the protrusions of the cores 50a and 50b and the lead portions 43a1, 43a2, 43b1, and 43b2 of the wires 41a and 41b by contact with protrusions from the substrate or the substrate itself.

[0150] As shown in Figure 3, in this embodiment, the cover member 100 covers at least a portion of the wire 44(41) wound around the bobbin 20 housed inside the case 90. Preferably, the cover member 100 covers the entire wound portion of the wires 41a and 41b, excluding the lead portions 45 and 46(42 and 43). By making the cover member 100 out of metal or the like, the effect of shielding leakage magnetic flux from the wound portion (coil portion) of the wires 41a and 41b is improved.

[0151] As shown in Figure 3, in this embodiment, the cover member 100 is molded integrally with the case 90. By molding the cover member 100 integrally with the case 90 by bending a metal plate or the like, the manufacturing of the cover member 100 and the case 90 becomes easier. Also, in this embodiment, the terminal block support portion 91 is molded integrally with the case 90. By molding the terminal block support portion 91 integrally with the case 90 by bending a metal plate or the like, the manufacturing of the terminal block support portion 91 and the case 90 becomes easier.

[0152] As shown in Figure 5A, in this embodiment, the bobbin 20 has a winding core 21 around which the wire is wound, and flanges 22a and 22b attached to the ends of the winding core 21. The flanges 22a and 22b also have protective hooks 23a, 23b, 24a, and 24b.

[0153] The protective hooks 23a, 23b, 24a, and 24b protrude upward from the upper opening 90a of the case 90 and, as shown in Figure 1A, guide the lead portions 43a1, 43a2, 43b1, and 43b2 of the wires 41a and 41b to the terminal block 70. By hooking the lead portions 43a1, 43a2, 43b1, and 43b2 of the wires 41a and 41b onto the protective hooks 23a, 23b, 24a, and 24b, it becomes easier to guide the lead portions 43a1, 43a2, 43b1, and 43b2 of the wires 41a and 41b to the terminals 61a, 61b, 62a, and 62b attached to the terminal block 70.

[0154] As shown in Figure 3, in this embodiment, the protective hook portions 23a, 23b, 24a, and 24b have a height h1 that is flush with or greater than the upper surface of the terminals 61a, 61b, 62a, and 62b. In addition, the connecting portions 67a, 67b, 68a, and 68b of the terminals 61a, 61b, 62a, and 62b to which the lead portions 43a1, 43a2, 43b1, and 43b2 of the wires 41a, 41b are connected are positioned at a height h2 lower than the upper surface of the terminals. By arranging them in this way, the protective hook portions 23a, 23b, 24a, and 24b effectively protect the connecting portions 67a, 67b, 68a, and 68b, and effectively prevent protrusions from the substrate (not shown) or the substrate itself from coming into contact with the connecting portions 67a, 67b, 68a, and 68b.

[0155] Furthermore, in this embodiment, the opening cover portion 101 is positioned at a height of H1 higher than the opening 90a of the case 90, and the protective hook portions 23a, 23b, 24a, and 24b are positioned between the opening cover portion 101 and the opening 90a. By arranging them in this way, the opening cover portion 101, together with the protective hook portions 23a, 23b, 24a, and 24b, protects the connecting wire portions 67a, 67b, 68a, and 68b, effectively preventing protrusions from the substrate or the substrate itself from coming into contact with the connecting wire portions 67a, 67b, 68a, and 68b.

[0156] Furthermore, in this embodiment, the cover member 100 shown in Figure 1A can also function as a cooling mechanism. By giving the cover member 100 a heat sink function, or by bringing the cover member 100 into contact with other cooling mechanisms, it is possible to dissipate heat from the heat-dissipating resin inside the case 90 to the outside through the cover member 100.

[0157] Furthermore, in this embodiment, since the middle leg portion 53a (53b) of the core 50a (50b) has the relationship described above, it is possible to further reduce the height and size while improving heat dissipation compared to a coil device having a core with a normal middle leg shape (upper and lower halves are the same).

[0158] The inside of the case 90 is filled with a heat-dissipating resin such as potting resin to cool the core 50a (50b) and wires 41a, 41b that are mounted on the bobbin 20. However, the height of the case 90 is restricted to the minimum necessary from the standpoint of reducing its height. Therefore, as shown in Figure 7, the liquid level S of the heat-dissipating resin contained inside the case 90 must be lower than the upper horizontal plane P1 including the upper end E1 of the middle leg portion 53a (53b) of the core 50a (50b). As a result, a portion of the upper end of the core (including the coil / hereinafter the same), including the upper end E1 of the middle leg portion 53a (53b) of the core 50a (50b), will not come into contact with the heat-dissipating resin.

[0159] In the coil device 10 according to the present invention, because it has the above-described configuration, the cross-sectional area, volume, and / or outer surface area of ​​the core 50a (50b) that does not come into contact with the heat-dissipating resin can be minimized. Furthermore, the cross-sectional area, volume, and / or outer surface area of ​​the core 50a (50b) that comes into contact with the heat-dissipating resin can be minimized. Therefore, in the coil device 10 according to this embodiment, it is possible to further reduce the height and size while improving heat dissipation compared to a coil device having a core with a normal mid-leg shape (upper and lower halves are the same).

[0160] Furthermore, in this embodiment, as shown in Figure 7, the upper surface 522a (522b) of the outer leg portion 52a (52b) and the upper end E1 of the middle leg portion 53a (53b) are substantially the same height. This configuration improves the balance of magnetic flux and enhances the characteristics.

[0161] Furthermore, in this embodiment, the lower end E2 of the middle leg portion 53a (53b) is located above the lower end of the outer leg portion 52a (52b), which is the lower surface of the outer leg 523a (523b). As shown in Figure 10, the wire 41a (41b) is wound around the middle leg portion 53a (53b) via the winding core portion 21 of the bobbin, so a gap is formed therefor.

[0162] Furthermore, as shown in Figure 7, in this embodiment, a lower recess (notch) 55a (55b) is formed in the base portion 51a (51b) located below the middle leg portion 53a (53b). Through the recess 55a (55b), heat-dissipating resin such as potting resin can easily enter the axial center of the core 50a (50b) near the bottom portion 90b of the case 90, thereby improving heat dissipation.

[0163] Furthermore, in this embodiment, similar to the middle leg portion 53a (53b), the volume of the lower half OL2 of the outer leg is made larger than the volume of the upper half OL1 of the outer leg, thereby enabling a lower profile and smaller size while improving heat dissipation. In addition, the balance of magnetic flux is improved, and the characteristics are enhanced.

[0164] Second Embodiment As shown in Figures 1B, 6B, and 6C, the coil device 20 according to this embodiment is the same as the coil device 10 of the first embodiment, except for the difference in the structure of the case 190 and the cover member 200, and similar effects can be expected. In the following description, the parts common to the first embodiment will be omitted.

[0165] As shown in Figures 6B and 6C, in this embodiment, the case 190 and the cover member 200 are each molded separately from a metal plate or the like, and are assembled as shown in Figure 1B.

[0166] Case 190 has a pair of locking pieces 90c1 and 90c2 integrally molded on the upper side along the Z axis of two opposite sides 90c, 90c located along the X axis. Locking holes 198a and 198b are formed in each locking piece 90c1 and 90c2, respectively.

[0167] As shown in Figure 6C, in this embodiment, the cover member 200 has an opening cover portion 201, a side cover portion 202, and a pair of cover support portions 203, 203. The side cover portion 202 is formed to protrude downward along the Z axis from one end along the Y axis of the opening cover portion 201. As shown in Figure 1B, the side cover portion 202 has an outer surface that is substantially perpendicular to the Y axis, and the outer surface of the side cover portion 202 may be substantially flush with the side surface 90d of the case 90, or recessed inward from the side surface 90d, or protrude slightly.

[0168] The cover support portions 203 and 203, which protrude downward along the Z-axis from both ends of the opening cover portion 201 along the X-axis, each have the same shape.

[0169] The cover support portion 203 has a locking piece 204 with an engaging projection at its tip, which is formed in an inverted U-shaped groove and extends upward along the Z-axis. The engaging projection is formed by bending the upper tip of the locking piece 204 so that it protrudes outward along the X-axis. The cover support portion 203 located above the locking piece 204 along the Z-axis and on both sides along the Y-axis is cut out to form an inverted U-shaped groove.

[0170] With this configuration, the locking piece 204 is held in a cantilevered support beam-like manner relative to the main part of the cover support 203, allowing for flexible elastic deformation, and the engaging projection can move elastically outward and inward along the X axis. Therefore, when the cover member 200 is inserted into the case 190 from the upper opening, the engaging projection of the locking piece 204 shown in Figure 6C easily engages with the locking hole 198a (198b), connecting the cover member 200 and the case 190.

[0171] Furthermore, the cover support portion 203 has a wide portion on both sides along the Y-axis of an inverted U-shaped groove that penetrates its front and back surfaces, with openings 206 formed that penetrate its front and back surfaces. A cover mounting portion 205 is formed on the lower side along the Z-axis of the wide portion of the cover support portion 203, and a notch that is recessed from bottom to top is formed approximately in the center along the Y-axis of the cover mounting portion 205.

[0172] Including this notch, the opening 206 and the U-shaped groove also serve as pathways for the potting resin to be filled inside the case 190, allowing the potting resin to be easily filled inside the case 190. In the coil device 20 of this embodiment, since the cover member 200 and the case 190 are separated, the cover member does not get in the way when housing a bobbin with a coil wound around it inside the case 190, and the work of bending the cover member relative to the case is also eliminated.

[0173] Third Embodiment As shown in Figure 11, the coil device according to this embodiment has a bobbin 120, terminals 161a, 162a, 161b, 162b, terminal block 170, and an insulating cover 180 as an option, and is the same as the first embodiment except that the terminal block 170 can be attached to the bobbin 120 in a one-touch manner. In the following description, the description of parts common to the first embodiment will be omitted.

[0174] As shown in Figure 11, the bobbin 120 has terminal block fixing portions 123a (123b) above each flange portion 122a, 122b located on both sides, along the Z axis. Further above the terminal block fixing portion 123a (123b), along the Z axis, there is an engaging recess 124a (124b). In addition, the terminal block fixing portion 123a (123b) has a fixing projection 130a (130b) formed thereon.

[0175] Furthermore, the terminal block 170 is provided with arm portions 172a (172b) at both ends along the X-axis, each having a hook portion 173a (173b) that fits into an engaging recess 124a (124b). The terminal block 170 also has fixing recesses 175a (175b) formed in a shape corresponding to the fixing protrusions 130a (130b). Additionally, stepped portions 174a (174b) are formed at both ends along the X-axis of the terminal block 170. The stepped lower surface 174a1 (174b1) of the stepped portion 174a (174b) is formed to further support the lower surface of the terminal block fixing portion 123a (123b) along the Z-axis from below.

[0176] In this embodiment, the engaging recess 124a (124b) and the arm portion 172a (172b) engage, the fixing projection 130a (130b) and the fixing recess 175a (175b) combine, and the stepped lower surface 174a1 (174b1) further supports the lower surface of the terminal block fixing portion 123a (123b) along the Z axis from below, thereby fixing the terminal block 170 to the bobbin 120.

[0177] Furthermore, the terminal cover (corresponding to the insulating member) 180 has a terminal cover bottom portion 181, which ensures insulation between the terminals 161a, 162a, 161b, and 162b mounted on the terminal block 170 and a case (not shown). In addition, terminal cover side portions 183a and 183b are formed on the outer side of the terminal cover 180 along the Y axis.

[0178] In this embodiment, the terminal cover 180 is provided with a gripping portion 184. The upper arm 184a and lower arm 184b of the gripping portion 184 grip the terminal cover mounting portion 178 of the terminal block 170 from above and below along the Z-axis, thereby fixing the terminal cover 180 to the terminal block 170.

[0179] This configuration makes it easy to arrange the terminals 161a, 162a, 161b, and 162b, to which the lead portions of the multiple wires wound around the core portion 121 of the bobbin 120 are connected, in a straight line in one or more rows along the opening edge of the case, and also facilitates the connection of each terminal to the circuit board.

[0180] Furthermore, the terminal block 170 can be arranged not only linearly along the X-axis on one side of the opening edge of the case, but also divided and arranged on both sides along the Y-axis of the case. For example, a terminal block with two terminals arranged in a row may be placed on one side, and a terminal block with the other two terminals arranged in a row may be placed on the other side.

[0181] It should be noted that the present invention is not limited to the embodiments described above, and can be modified in various ways within the scope of the present invention.

[0182] For example, the heat-dissipating resin is not limited to potting resin; other resins with excellent heat dissipation properties may also be used. The heat-dissipating resin may consist of, for example, a silicone resin, urethane resin, or epoxy resin that remains flexible even after injection. The resin's Young's modulus is preferably 0.1 to 100 MPa, and its Shore A hardness is preferably 100 or less, more preferably 60 or less. Furthermore, to enhance heat dissipation, a filler with high thermal conductivity may be added to the resin.

[0183] Furthermore, in the first or second embodiment described above, as shown in Figure 6A or Figure 6B, the terminal block support portion 91 is formed only at one location on one side in the Y-axis direction of the upper opening 90a of the case 90 or 190, but this is not limited to this. For example, multiple terminal block support portions 91 may be formed in the same manner as in the embodiments described above at two or more locations on both sides in the Y-axis direction of the upper opening 90a of the case 90 or 190 as shown in Figure 6A or Figure 6B, or at two or more locations on both sides in the X-axis direction of the upper opening 90a of the case 90 or 190. Alternatively, separate from the terminal block support portions 91 described above, another terminal block support portion may be formed facing outwards at any position in the upper opening 90a of the case 90 or 190, and multiple terminal block support portions 91 may be formed in the same manner as in the embodiments described above.

[0184] In any case, when forming multiple terminal block support sections in the case, Multiple terminal blocks 70 and insulating members 80, as shown in Figure 9A, may be prepared and attached to each terminal block support.

[0185] Furthermore, the cores 50a and 50b are not limited to E-type cores, but may be a combination of two E-type cores, or a combination of an E-type core and an I-type core, or a combination of cores of other shapes. In any case, each of the cores 50a and 50b has at least two intermediate legs 53a and 53b that are inserted into the axial hole 211 of the winding core portion 21 of the bobbin 20. [Explanation of symbols]

[0186] 10…Coil device (transformer) 20,120... Bobbin 21,121,122a,122b…Winding core part 211... Through hole 22a, 22b…Tsubabe 220a, 220b... Flange body 23a, 23b, 24a, 24b... Protective hook section 23a1, 23b1, 24a1, 24b1... Hook support section 25a, 25b, 26a, 26b… Core isolation walls 27a, 27b... Extended flange 28a, 28b... Notches 32a, 32b... Mounting section 33,34...Protrusion 35, 36… Through holes 37a, 37b...concave bottom 123a, 123b…Terminal block fixing part 124a, 124b... Engaging recess (terminal block engagement part) 130a, 130b... Fixed protrusions 41a, 41b... wire 42a, 42b... Coil section 43a1, 43a2, 43b1, 43b2… Lead section 50a, 50b... core 51a, 51b... Base section 510a,510b…External surface 511a, 511b...inner surface 512a, 512b...Top surface 513a, 513b…bottom surface 52a, 52b...Outer leg part 520a, 520b... Medial surface of the outer leg 521a, 521b...Outer leg end surface 522a, 522b…Top surface of outer leg 523a, 523b…lower surface of outer leg 53a,53b...middle leg 531a, 531b... Middle leg end surface 55a, 55b... recessed (notched) 550a, 550b…Inner peripheral surface 551a, 551b... Tapered surface 56a, 56b…thick part 61a, 61b, 62a, 62b, 161a, 162a, 161b, 162b… terminals 63a, 63b, 64a, 64b... Main terminal section 63a1~63a4, 63b1~63b4, 64a1~64a4, 64b1~64b4...Mounting claw 65a, 65b, 66a, 66b… Connection holes 67a, 67b, 68a, 68b...Connection section 67a1,67b1,68a1,68b1...Folding piece 163a, 164a, 163b, 164b... Main terminal section 167a,168a,167b,168b...connection part 70,170…Terminal block 701...Terminal block base 71a, 71b, 72a, 72b…fastener placement hole 71a1,71b1,72a1,72b1...Terminal fixing part 73a1~73a4, 73b1~73b4, 74a1~74a4, 74B1~74b4… Mounting claw holes 75a, 75b... Engaging protrusions 76…Engagement notch 77... Terminal separation wall fitting groove 78a,78b,79a,79b...fastener 172a, 172b... Arm section (bobbin engagement section) 173a, 173b... Hook portion (bobbin engagement portion) 174a, 174b... Stepped section 174a1,174b1…bottom surface of step 175a, 175b… Fixed recess 178... Terminal cover mounting area 180... Terminal cover (insulating component) 181...Bottom of terminal cover 183a, 183b... Terminal cover side 184...Gripping part 184a... Upper arm 184b... Lower arm 80...Insulation-securing component 81...Insulating sheet section 82...middle part 83a, 83b, 84a, 84b... intermediate convex parts 83a1, 83b1, 84a1, 84b1… Storage recesses 83a2,83b2…fixing protrusion 83a3, 83b3, 84a3, 84b3...fastener placement part 85a, 85b…Middle through hole 86...Intermediate engagement part 861...Engaging claw 87…Terminal separation wall 88...Central protrusion 90,190... cases 90a... Upper opening 90b…Bottom surface 90c,90d…side 91...Terminal block support part 92a, 92b, 93a, 93b…Support through hole 94a, 94b…Engagement hole 95...Central hole 96...Opening edge 97a, 97b...Position adjustment section 198a, 198b…Lock hole 100,200... Cover components 101,201...Opening cover section 102,202… Side cover section 203... Cover support part 204... Locking piece 205...Cover mounting section 206…Opening 210…Potting resin

Claims

1. A bobbin having a core around which the wire is wound, A core having a middle leg portion that is inserted into the axial hole of the aforementioned winding core portion, A case in which the bobbin to which the core is attached is housed, A coil device having, The bobbin is positioned inside the case such that the winding axis of the wire is substantially parallel to the bottom surface of the case. When the middle leg is divided into an upper half and a lower half by an intermediate horizontal plane passing through the midpoint of the vertical distance line that connects the upper horizontal plane including the upper end of the middle leg and the lower horizontal plane including the lower end of the middle leg in the shortest possible distance, The middle leg portion has a cross-sectional shape such that the area of ​​the lower half of the cross-section (CA2) is larger than the area of ​​the upper half of the cross-section (CA1), The aforementioned core is The base portion to which the base end of the aforementioned middle leg portion is connected, It has outer legs connected to the base portion and positioned on both sides of the middle leg portion, The lower end of the middle leg portion is located above the lower end of the outer leg portion. A notch is formed in the base portion located below the aforementioned middle leg portion. The case is filled with potting resin, The liquid level of the potting resin is lower than the upper end of the middle leg portion by a predetermined length (T1). The ratio (T1 / T0) of the predetermined length (T1) of the liquid level of the potting resin to the length (T0) from the lower end to the upper end of the middle leg portion is 1 / 5 to 1 / 3. Each of the lower ends of the outer leg portion has a thicker section formed thereon compared to the upper end of the outer leg portion. Coil device.

2. A bobbin having a core around which the wire is wound, A core having a middle leg portion that is inserted into the axial hole of the aforementioned winding core portion, A case in which the bobbin to which the core is attached is housed, A coil device having, The bobbin is positioned inside the case such that the winding axis of the wire is substantially parallel to the bottom surface of the case. When the middle leg is divided into an upper half and a lower half by an intermediate horizontal plane passing through the midpoint of the vertical distance line that connects the upper horizontal plane including the upper end of the middle leg and the lower horizontal plane including the lower end of the middle leg in the shortest possible distance, The middle leg portion has a shape such that the volume of the lower half (V2) is larger than the volume of the upper half (V1), The aforementioned core is The base portion to which the base end of the aforementioned middle leg portion is connected, It has outer legs connected to the base portion and positioned on both sides of the middle leg portion, The lower end of the middle leg portion is located above the lower end of the outer leg portion. A notch is formed in the base portion located below the aforementioned middle leg portion. The case is filled with potting resin, The liquid level of the potting resin is lower than the upper end of the middle leg portion by a predetermined length (T1). The ratio (T1 / T0) of the predetermined length (T1) of the liquid level of the potting resin to the length (T0) from the lower end to the upper end of the middle leg is 1 / 5 to 1 / 3. Each of the lower ends of the outer leg portion has a thicker section formed thereon compared to the upper end of the outer leg portion. Coil device.

3. A bobbin having a core around which the wire is wound, A core having a middle leg portion that is inserted into the axial hole of the aforementioned winding core portion, A case in which the bobbin to which the core is attached is housed, A coil device having, The bobbin is positioned inside the case such that the winding axis of the wire is substantially parallel to the bottom surface of the case. When the middle leg is divided into an upper half and a lower half by an intermediate horizontal plane passing through the midpoint of the vertical distance line that connects the upper horizontal plane including the upper end of the middle leg and the lower horizontal plane including the lower end of the middle leg in the shortest possible distance, The middle leg portion has a shape such that the area of ​​the lower half of the outer surface (OA2) is larger than the area of ​​the upper half of the outer surface (OA1), The aforementioned core is The base portion to which the base end of the aforementioned middle leg portion is connected, It has outer legs connected to the base portion and positioned on both sides of the middle leg portion, The lower end of the middle leg portion is located above the lower end of the outer leg portion. A notch is formed in the base portion located below the aforementioned middle leg portion. The case is filled with potting resin, The liquid level of the potting resin is lower than the upper end of the middle leg portion by a predetermined length (T1). The ratio (T1 / T0) of the predetermined length (T1) of the liquid level of the potting resin to the length (T0) from the lower end to the upper end of the middle leg is 1 / 5 to 1 / 3. Each of the lower ends of the outer leg portion has a thicker section formed thereon compared to the upper end of the outer leg portion. Coil device.

4. The coil device according to any one of claims 1 to 3, wherein when each of the outer leg portions is divided into an upper half and a lower half by the intermediate horizontal plane, the outer leg portion has a shape such that the volume of the lower half (OV2) is greater than the volume of the upper half (OV1) of the outer leg portion.

5. The case is provided with a cover member that covers a portion of the upper opening of the case with a predetermined gap. The coil device according to any one of claims 1 to 4, wherein the cover member covers at least a portion of the wire wound around the bobbin housed inside the case.

6. The coil device according to claim 5, wherein the cover member is molded integrally with the case.

7. The case has a terminal block support portion that protrudes outward from the edge of the upper opening of the case, The coil device according to any one of claims 1 to 6, wherein a terminal block is arranged on the terminal block support portion.

8. The coil device according to claim 7, wherein the terminal block has a plurality of terminals arranged substantially parallel to the winding shaft of the wire.

9. The coil device according to any one of claims 1 to 3, wherein a through hole is formed in the lower part of the outer circumferential surface of the winding core portion of the bobbin, leading to the lower end of the middle leg portion.

Images