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 potting resin, thereby enhancing heat dissipation.

[0003] However, in recent years, there has been a demand for lowering the height 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 low-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 axial 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 portion 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 shortest connects between the upper horizontal plane including the upper end of the middle leg portion and the lower horizontal plane including the lower end of the middle leg portion, The middle leg portion has a cross-sectional shape in which the cross-sectional area (CA2) of the lower half is larger than the cross-sectional area (CA1) of the upper half.

[0007] Also, a coil device according to a second aspect of the present invention is 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 portion 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 shortest connects between the upper horizontal plane including the upper end of the middle leg portion and the lower horizontal plane including the lower end of the middle leg portion, The middle leg portion has a shape in which the volume (V2) of the lower half is larger than the volume (V1) of the upper half.

[0008] Furthermore, a coil device according to a third aspect of the present invention is 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 portion 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 shortest connects between the upper horizontal plane including the upper end of the middle leg portion and the lower horizontal plane including the lower end of the middle leg portion, The middle leg portion has a shape in which the outer peripheral surface area (OA2) of the lower half is larger than the outer peripheral surface area (OA1) of the upper half.

[0009] In the coil device according to the present invention (first to third aspects), the bobbin is disposed inside the case such that the winding axis of the wire is substantially parallel to the bottom surface of the case. That is, the coil device of the present invention is a horizontal coil device, and can be easily made lower-profile compared to a vertical coil device in which the winding axis of the wire is substantially perpendicular to the bottom surface of the case.

[0010] Also, by filling the inside of the case with a heat-dissipating resin such as potting resin, etc., heat from the wire or the bobbin (including the core) can be released to the bottom surface of the case through the heat-dissipating resin, improving heat dissipation.

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

[0012] In the coil device of the present invention, since it has a core with a middle leg portion having such a relationship, 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 (where the upper half and the lower half are the same).

[0013] The inside of the case is filled with a heat-dissipating resin such as potting resin to cool the core and wire attached to the bobbin, but the height of the case is regulated to the minimum necessary from the perspective of making it lower-profile. Therefore, the liquid level of the heat-dissipating resin accommodated inside the case has to be lower than the upper horizontal plane including the upper end of the middle leg portion of the core. Therefore, a part of the upper end of the core including the upper end of the middle leg portion of the core does not come into contact with the heat-dissipating resin.

[0014] In the coil device according to the present invention, since it has the above-described configuration, it is possible to minimize the cross-sectional area, volume, and / or the area of the outer peripheral surface of the core of the portion that does not contact the heat-dissipating resin. Also, it is possible to minimize the cross-sectional area, volume, and / or the area of the outer peripheral surface of the core of the portion that contacts the heat-dissipating resin. Therefore, in the coil device according to the present invention, it is possible to improve the heat dissipation while further reducing the height and size compared to a coil device having a core with a normal middle leg shape (where the upper half and the lower half are the same).

[0015] The core may have a base portion to which the base end portion of the middle leg portion is connected, and outer leg portions that are connected to the base portion and are disposed on both sides of the middle leg portion. That is, the core may have a so-called E-shaped core, and may be a combination of an E-shaped core and an E-shaped core, or a combination of an E-shaped core and an I-shaped core, 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 shaft hole of the bobbin's winding core portion.

[0016] Preferably, the upper end of the outer leg portion and the upper end of the middle leg portion have substantially the same height. By having such a configuration, the balance of the magnetic flux is improved and the characteristics are enhanced.

[0017] Preferably, the lower end of the middle leg portion is located above the lower end of the outer leg portion. Since a wire is wound around the middle leg portion via the winding core portion of the bobbin, a gap is formed for that purpose. Also, preferably, a notch is formed in the base portion located below the middle leg portion. Through the notch, near the bottom of the case, a heat-dissipating resin such as potting resin can easily enter the central portion in the axial direction of the core, improving the 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 is possible to reduce the height and size while improving the heat dissipation. Also, the balance of the 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 a cover member with a predetermined gap, 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 separately molded 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] In addition, the cover member can also function as a cooling mechanism. By giving the cover member a heat sink-like function or by bringing the cover member into contact with other cooling mechanisms, it is also possible to release heat from the heat-dissipating resin inside the case to the outside through the cover member.

[0024] The case may have a terminal block support portion that protrudes outward from the edge of the upper opening of the case. By configuring it in this way, it is not necessary to increase the installation area of the case corresponding to the area of the terminal block, and the installation area of the case can be reduced while being horizontal.

[0025] Furthermore, a terminal block may be arranged on the terminal block support portion, or a 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 the substrate arranged above the coil device, the terminal block support portion facilitates the connection to the substrate and improves the reliability in order to reinforce the strength of the terminal block.

[0026] Preferably, a plurality of terminals are arranged on the terminal block substantially parallel to the reel of the wire. By configuring it in this way, it becomes easy to arrange in a straight line in one row or multiple rows along the opening edge of the case the terminals to which the lead portions of the plurality of wires wound around the bobbin core portion are connected, and it also becomes easy to connect each terminal to the substrate.

[0027] Furthermore, in the coil device of the present invention, the terminal block may be attached on the terminal block support portion via an insulation ensuring member. By configuring it in this way, after winding a plurality of wires around the bobbin and attaching a plurality of terminals to the terminal block, the operation of connecting the lead portions of the plurality of wires to the plurality of terminals at once becomes easy. For the connection of the lead portion of the wire to the terminal, for example, thermocompression bonding such as crimping is used.

[0028] When connecting the lead portion of the wire to the terminal, it is necessary to press a thermocompression bonding jig or the like from both sides of the lead portion. Before attaching the insulation ensuring member to the terminal block, it is easy to press a thermocompression bonding jig or the like from both sides of the lead portion. Also, after connecting the lead portion of the wire to the terminal, since the insulation ensuring member is disposed on one side of the joint portion between the terminal and the lead portion of the wire, the insulation between the joint portion and the core attached to the bobbin can be effectively ensured. Further, the insulation ensuring member can also ensure the insulation between the lead portion and the joint portion of the terminal and the case.

[0029] Preferably, the insulation ensuring member has an insulation sheet portion, The insulation sheet portion is disposed between the joint portion between the lead portion of the wire and the terminal and the outer leg portion of the core mounted on the bobbin. By configuring in this way, the insulation ensuring member can enhance the insulation between the joint portion between the lead portion and the terminal and the outer leg portion of the core mounted on the bobbin. Further, the insulation ensuring member can also improve the insulation between the lead portion and the joint portion of the terminal and the case.

[0030] Preferably, the insulation ensuring member further has an intermediate portion integrally formed with the insulation 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. By the intermediate engaging portion such as an engaging claw engaging with the terminal block, the attachment while positioning the terminal block and the insulation ensuring member becomes easy. Also, the terminal block and the insulation ensuring member can be fixed without using an adhesive. However, an adhesive may be used.

[0031] Preferably, the intermediate portion has an intermediate convex portion that enters a support through hole formed in the terminal block support portion. By the intermediate convex portion entering the support through hole, the positioning between the insulation ensuring member and the terminal block support portion becomes easy.

[0032] The middle convex portion may have a receiving recess that opens toward the terminal block. The receiving recess may be configured such that a screw portion for attaching the terminal to the terminal block can enter. The receiving recess can accommodate metal dust or the like when the screw portion for attaching the terminal to the terminal block is screwed together.

[0033] The terminal block may have an engaging convex portion that engages with an engaging hole formed in the terminal block support portion through an intermediate through-hole formed in the intermediate portion. By engaging the engaging convex portion with the engaging hole formed in the terminal block support portion through the intermediate through-hole, the positioning between the terminal block and the insulation ensuring member is achieved, and the attachment while positioning between the terminal block and the terminal block support portion becomes easy. Also, without using an adhesive, the terminal block, the insulation ensuring member, and the terminal block support portion can be fixed. However, an adhesive may also be used.

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

[0035] Preferably, the protective hook portion has a height flush with or higher than the upper surface of the terminal, and the connection portion between the lead portion of the wire and the terminal is arranged at a position lower than the upper surface of the terminal. By arranging it in this way, the protective hook portion can protect the connection portion and effectively prevent the protruding portion from the substrate or the substrate itself from contacting the connection portion.

[0036] Also, preferably, the protective hook portion is preferably lower than the lower surface of the cover member. By arranging it in this way, the cover member, together with the protective hook portion, can protect the connection portion and effectively prevent the protruding portion from the substrate or the substrate itself from contacting the connection portion.

[0037] In addition, the configurations of the terminals and the terminal block are not limited to the above, and the terminal block may be attached to the flange portion of the bobbin. For example, terminal block engaging portions may be integrally formed on each of the flange portions located on both sides of the bobbin. The bobbin engaging portions (for example, arm portions) provided at both ends along the longitudinal direction of the terminal block may be fitted into these terminal block engaging portions (for example, engaging recesses), and the terminal block may be configured to be fitted and attached to the bobbin.

[0038] By configuring in this way, it becomes easy to arrange linearly in one row or multiple rows along the opening edge of the case the terminals to which the lead portions of the plurality of wires wound around the core portion of the bobbin are connected, and it also becomes easy to connect each terminal to the substrate.

[0039] In addition, the terminal block can be not only arranged linearly along the X-axis only on one side of the opening edge of the case, but also arranged by being divided into both sides along the Y-axis of the case. For example, a terminal block in which two terminals are arranged may be arranged on one side, and a terminal block in which the other two terminals are arranged may be arranged on the other side.

Brief Description of the Drawings

[0040]

Figure 1A

Figure 1B

Figure 2

Figure 3

Figure 4

Figure 5A

Figure 5B

Figure 6A

Figure 6B

Figure 6C

Figure 7

Figure 8

Figure 9A

Figure 9B

Figure 10

Figure 11

DETAILED DESCRIPTION OF THE INVENTION

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

[0042] First Embodiment As an example of the coil device 10 according to the present embodiment shown in FIG. 1A, it functions as, for example, a transformer and is used in an in-vehicle charger for an EV (Electric Vehicle), a PHV (Plug-in Hybrid Vehicle), or a commuter (vehicle), or a power supply circuit for household or industrial electrical equipment, or a power supply circuit for computer equipment.

[0043] The detailed configuration of the coil device 10 will be described below. In the following description, in the drawings, the X-axis, Y-axis, and Z-axis are perpendicular to each other. Also, the side facing the center of the coil device 10 is defined as the inner side or the inner direction, and the side away from the center of the coil device 10 is defined as the outer side or the outer direction.

[0044] As shown in FIG. 2, the coil device 10 includes a bobbin 20, wires 41a, 41b, cores 50a and 50b, terminals 61a, 61b, 62a, 62b, a terminal block 70, an insulation securing member 80, and a case 90. The coil device 10 is a horizontal coil device arranged such that the winding axes C of the coil portions 42a, 42b of the wires 41a, 41b are 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, 41b, and the Y-axis substantially coincides with the direction in which the lead portions 43a1, 43a2, 43b1, 43b2 of the wires 41a, 41b are drawn out. The Z-axis corresponds to the height (thickness) direction of the coil device 10. In this embodiment, the upper side along the Z-axis of the coil device 10 is the installation surface of the circuit board to which the terminals 61a, 61b, 62a, 62b of the coil device 10 (transformer) are connected.

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

[0047] As shown in FIG. 10, the coil portion 42a (42b) formed by the wire 41a (41b) is one layer or two or more layers in the direction (radial direction) perpendicular to its winding axis. As shown in FIG. 2, the winding axes C of the coil portions 42a, 42b substantially coincide and are each parallel to the X-axis.

[0048] As shown in FIG. 2, the coil part 42a is wound around one side along the X-axis of the bobbin part, and the coil part 42b is wound around the other side along the X-axis of the bobbin part. Either one of the coil parts 42a and 42b constitutes the primary coil, and the other of the coil parts 42a and 42b constitutes the secondary coil. The arrangement of each of the primary coil and the secondary coil in the bobbin part may be either on one side or the other side along the X-axis of the bobbin part.

[0049] The wires 41a and 41b are each constituted of, for example, insulated covered wires, and are constituted of conductive wires such as copper wires covered with an insulating layer. The conductive wires of the wires 41a and 41b may each be constituted of a single wire or may be constituted of a stranded wire. The wire diameter (diameter) of the wires 41a and 41b is not particularly limited, and is, for example, 1.0 to 3.0 mm. The wire diameters of the wires 41a and 41b may be equal to each other, or may be different. For example, among the wires 41a and 41b, the wire diameter of the wire through which a large current flows may be made thicker than the wire diameter of the other wire.

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

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

[0052] The cores 50a and 50b each have the same shape (e.g., E-shaped and E-shaped), but may have different shapes (e.g., E-shaped and I-shaped). In the present embodiment, the core 50a has a base portion 51a, a pair of outer leg portions 52a, and a middle leg portion 53a. The core 50b has a base portion 51b, a pair of outer leg portions 52b, and a middle leg portion 53b. Hereinafter, the configuration of the core 50a will be described, but the description of the core 50a also applies to the core 50b. Therefore, unless particularly necessary, the description of the configuration of the core 50b will be omitted.

[0053] The base portion 51a has a predetermined thickness along the X-axis and has a predetermined length along each of the Y-axis and the Z-axis as shown in FIG. 7. Hereinafter, as shown in FIG. 2, in the base portion 51a, the outer surface along the X-axis is referred to as the outer surface 510a, the inner surface along the X-axis is referred to as the inner surface 511a, the upper surface is referred to as the upper surface 512a, and the lower surface is referred to as the lower surface 513a. Also, in the base portion 51b, the outer surface along the X-axis is referred to as the outer surface 510b, the inner surface along the X-axis is referred to as the inner surface 511b, the upper surface is referred to as the upper surface 512b, and the lower surface is referred to as the lower surface 513b.

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

[0055] On the lower surface 513a of the base portion 51a, a concave portion (notch) 55a that is recessed upward along the Z-axis is formed at the position of the middle leg portion 53a. The concave portion 55a is formed at a substantially central portion of the base portion 51a with respect to the Y-axis and has a predetermined width along the X-axis and the Y-axis. The width of the concave portion 55a along the Y-axis is smaller than the width of the middle leg portion 53a along the Y-axis and is substantially equal to the width of the concave bottom portion 37a or 37b of the bobbin 20 shown in FIG. 5B along the Y-axis. The concave portion 55a shown in FIG. 7 is formed so as to penetrate from the inner surface to the outer surface of the base portion 51a.

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

[0057] The inner peripheral surface 550a of the recess 55a may have tapered surfaces 551a on both sides along the Y-axis. The tapered surfaces 551a are formed so that the width of the recess 55a along the Y-axis becomes narrower as it goes upward from the lower surface 513a. The shape of the recess 55a substantially coincides with the shape of the concave bottom 37a or 37b of the bobbin 20 shown in FIG. 5B, but it may be different.

[0058] As shown in FIG. 2, the middle leg portion 53a is disposed 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 with a predetermined length and is disposed 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 disposed inside the through hole 211 with their respective end faces 531a and 531b butted 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 FIG. 7, in the present embodiment, the cross section (a section perpendicular to the X-axis) of the middle leg portion 53a (53b) has a downwardly bulging shape. That is, at the intermediate horizontal plane P0 passing through the midpoint of the vertical distance line that connects the shortest between the upper horizontal plane P1 including the upper end (along the Z-axis) E1 of the middle leg portion 53a (53b) and the lower horizontal plane P2 including the lower end (along the Z-axis) E2 of the middle leg portion 53a (53b), the middle leg portion 53a (53b) is divided into an upper half ML1 and a lower half ML2. The intermediate horizontal plane P0 is a plane including the central axis (the center along the Z-axis) O of the middle leg portion 53a (53b).

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

[0061] In the present 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. Further, OA2 / OA1 is preferably 1.30 to 2.00, more preferably 1.67 to 2.00. By setting such a range, while reducing the height and size of the device 10, the heat dissipation performance by the potting resin can be enhanced.

[0062] Also, in the present embodiment, the liquid level S of the potting resin described later is lower than the upper end E1 (along the Z axis) of the middle leg portion 53a (53b) by a predetermined height T1. By doing so, the height reduction of the coil device 10 including the case 90 shown in FIG. 1A can be achieved.

[0063] In the present embodiment, T1 / T0 is preferably 0 to 1 / 3, more preferably 1 / 5 to 1 / 3. By setting such a range, while reducing the height of the device 10, the heat dissipation performance by the potting resin can be enhanced. Note that from the viewpoint of improving the heat dissipation performance at the expense of height reduction, the liquid level P1 of the potting resin may be above the upper end E1 of the middle leg portion 53a (53b).

[0064] Further, in the present embodiment, the Z-axis position of the upper end E1 of the outer peripheral surface of the middle leg portion 53a is substantially the same as the Z-axis position with respect to the upper surface 512a of the base portion 51a, and it is preferable that the upper vertex along the Z-axis of the middle leg portion 53a is connected to the upper surface 512a of the base portion 51a without a step. However, the Z-axis position of the upper end E1 of the outer peripheral 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. Further, the lower portion including the lower end E2 of the outer peripheral surface of the middle leg portion 53a is disposed at a position close to the inner peripheral surface 550a of the concave portion 55a, and is preferably located above the inner peripheral surface 550a, but is not limited thereto.

[0065] As shown in FIG. 2, the pair of outer leg portions 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 leg portions 52a is disposed at one end along the Y-axis of the inner surface 511a, and the other of the pair of outer leg portions 52a is disposed at the other end along the Y-axis of the inner surface 511.

[0066] As shown in FIG. 7, the outer leg inner surface 520a of the outer leg portion 52a curves inward along the Y-axis as it extends upward and downward from the intermediate horizontal plane P0 along the Z-axis of the outer leg portion 52a. Further, the curved portion of the outer leg inner surface 520a curves at a predetermined interval along the outer peripheral surface of the middle leg portion 53a. Further, the curved portion of the outer leg inner surface 520a curves along the outer peripheral edge of the flange portion 22a (flange body 220a) of the bobbin 20 shown in FIG. 5A.

[0067] Note that the outer surface of the outer leg portion 52a located on the opposite side of the outer leg inner surface 520a shown in FIG. 7 along the Y-axis has a plane perpendicular to the Y-axis and has a shape different from the curved shape of the outer leg inner surface 520a. Further, a thick portion 56a having a greater thickness in the Y-axis direction than the upper end portion of the outer leg portion 52a is formed at the lower end portion of each of the pair of outer leg portions 52a (52b) along the Z-axis. The inner surface 520a (520b) of the thick portion 56a protrudes inward along the Y-axis and forms a plane perpendicular to the Y-axis.

[0068] In the present embodiment, by forming the thick portion 56a on the outer leg portion 52a, it becomes possible to sufficiently secure the area covered by the potting resin of the outer leg portion 52, and the coil device 10 having good inductance characteristics can be obtained.

[0069] Further, in the present embodiment, when each of the outer leg portions 52a (52b) is divided into an upper half OL1 and a lower half OL2 of the outer leg at the intermediate horizontal plane P0, the volume (OV2) of the lower half OL2 of the outer leg is larger than the volume (OV1) of the upper half OL1 of the outer leg. The outer leg portion 52a (52b) has such a shape.

[0070] Similar to the middle leg portions 53a (53b), the outer leg portions 52a (52b) can also improve heat dissipation while reducing the height and size by making the volume of the lower half OL2 of the outer leg larger than the volume of the upper half OL1 of the outer leg. Also, the balance of the magnetic flux is improved and the characteristics are enhanced.

[0071] In the present 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 peripheral surface of the outer leg portion, similar to the middle leg portions 53a (53b).

[0072] As shown in FIG. 2, the pair of outer leg portions 52a extend from the inner surface 511a along the X-axis by a predetermined length, similar to the middle leg portion 53a, and are disposed outside the winding core portion 21 of the bobbin 20. Also, the middle leg portion 53a is inserted into the through hole 211 of the bobbin 20.

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

[0074] On the outer peripheral surface of the bobbin core portion 21, wires 41a and 41b shown in FIG. 2 are wound to form coil portions 42a and 42b. Coil portion 42a is disposed between flange portion 22a and projection portion 33 (34) on one side along the X-axis of the bobbin core portion 21 shown in FIG. 5A. Further, coil portion 42b shown in FIG. 2 is disposed between flange portion 22b and projection portion 33 (34) on the other side along the X-axis of the bobbin core portion 21 shown in FIG. 5A.

[0075] As shown in FIG. 2, one end along the winding axis of coil portion 42a is disposed at a position adjacent to flange portion 22a, and the other end along the winding axis of coil portion 42a is disposed at a position adjacent to projection portions 33 and 34. Further, one end along the winding axis of coil portion 42b is disposed at a position adjacent to flange portion 22b, and the other end along the winding axis of coil portion 42b is disposed at a position adjacent to projection portions 33 and 34.

[0076] As shown in FIG. 5B, the bobbin core portion 21 is a cylindrical body, and the through-hole 211 of the bobbin core portion 21 has a downwardly bulging shape in its cross-section corresponding to the cross-section of middle leg portion 53a shown in FIG. 7. The axis of the bobbin core portion 21 is parallel to the X-axis. Inside the through-hole 211, middle leg portions 53a and 53b of cores 50a and 50b can be accommodated while creating a predetermined gap (which may be 0 in part) on its outer peripheral surface.

[0077] As shown in FIG. 5A, a through-hole 35 penetrating the inside and outside of the bobbin core portion 21 is formed in the upper portion of the outer peripheral surface of the bobbin core portion 21. Through-hole 35 is located at a substantially central portion of the bobbin core portion 21 with respect to the X-axis and the Y-axis, and is located between projection portions 33, 33. Through-hole 35 has a substantially elliptical opening having a long diameter along the X-axis. The cross-sectional shape of through-hole 35 has a shape corresponding to the cross-sectional shapes of middle leg portions 53a and 53b, and middle leg portions 53a and 53b can be inserted into through-hole 35 with a predetermined gap.

[0078] As shown in FIG. 5B, a through hole 36 penetrating the inside and outside of the core part 21 is also formed in the lower part of the outer peripheral surface of the core part 21. The through hole 36 is located at a substantially central part of the core part 21 with respect to the X-axis and the Y-axis, and is located between the protruding parts 34, 34. The through hole 36 has a substantially elliptical opening having a long diameter along the X-axis. Along the Z-axis, the through hole 36 is formed at a position opposite to the through hole 35.

[0079] By forming the through holes 35 and 36 in the core part 21, it becomes possible to circulate the potting resin 210 (see FIG. 10) inside and outside the bobbin 20 (core part 21) through these through holes 35, 36, and the potting resin 210 can be spread to every corner in the case 90.

[0080] As shown in FIG. 5A, the flange part 22a is formed at one end along the axis of the core part 21, and the flange part 22b is formed at the other end along the axis of the core part 21. The flange part 22a and the flange part 22b have the same shape respectively, but they may be different. The flange part 22a has a flange main body 220a extending in the circumferential direction along the outer peripheral surface of the core part 21 at one end along the X-axis of the core part 21. The flange part 22b has a flange main body 220b extending in the circumferential direction along the outer peripheral surface of the core part 21 at the other end along the Y-axis of the core part 21.

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

[0082] As shown in FIG. 5B, below the flange body 220a, a pair of mounting portions 32a are formed 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 one mounting portion 32a and the other mounting portion 32a are arranged at a predetermined interval along the Y-axis. The pair of mounting portions 32a extend substantially parallel to the YZ plane with respect to the flange body 220a, and the bottom surfaces of the pair of mounting portions 32a are substantially flat surfaces flush with each other. The pair of mounting portions 32a are placed on the bottom surface 90b of the case 90 shown in FIG. 2.

[0083] As shown in FIG. 5B, below the flange body 220b, a pair of mounting portions 32b are formed in the same manner as the pair of mounting portions 32a. Since the configuration and function of the pair of mounting portions 32b are the same as those of the pair of mounting portions 32a, detailed description thereof will be omitted. Through the pair of mounting portions 32a and the pair of mounting portions 32b, it is possible to support the bobbin 20's winding core portion 21 and the like.

[0084] Between each of the pair of mounting portions 32a, a concave bottom portion 37a is formed, and between each of the pair of mounting portions 32b, a concave bottom portion 37b is formed. The concave bottom portions 37a and 37b have a shape that is recessed upward from the positions of the bottom surfaces of the mounting portions 32a and 32b. On both sides of the inner peripheral surfaces of the concave bottom portions 37a and 37b, portions that are tapered are formed.

[0085] The inner peripheral surface shapes of the concave bottom portions 37a and 37b preferably correspond to the inner peripheral surface shapes of the recesses 55a (55b) formed in the core 50a (50b) shown in FIG. 7 and are substantially the same shape, but they may also be larger or smaller than that. As shown in FIG. 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 peripheral surface of the winding core portion 21, or may be lower than that.

[0086] By forming concave bottoms 37a and 37b in flange body parts 220a and 220b, the concave bottoms 37a and 37b function as flow channels for potting resin 210 (Fig. 10) when the potting resin 210 is filled. For example, the potting resin 210 flows through the inside (outside) of the concave bottom 37a (37b) from the inside (outside) along the X-axis of the concave bottom 37a (37b) toward the outside (inside), and the potting resin 310 can be spread particularly below the bobbin 20.

[0087] From the viewpoint of improving the heat dissipation by making the flow of the potting resin in the X-axis direction good, it is preferable that the sizes of the concave bottoms 37a and 37b are larger, but it is determined by the balance with the strength of the mounting parts 32a and 32b and the like. This is the same for the recesses 55a (55b) formed in the cores 50a (50b) shown in Fig. 7.

[0088] As shown in Fig. 5A, above the flange body part 220a, protective hook parts 23a and 24a are formed side by side along the Y-axis. The protective hook parts 23a and 24a are connected above the flange body part 220a via protective hook holding parts 23a1 and 24a1. Core separation walls 25a and 26a are formed in the protective hook holding parts 23a1 and 24a1. The core separation walls 25a and 26a project outward along the X-axis and face the protective hook parts 23a and 24a.

[0089] Above the flange body part 220a, an extended flange part 27a is formed. The extended flange part 27a is integrally connected above the flange body part 220a and extends substantially parallel to the YZ plane with respect to the flange body part 220a. That is, the extended flange part 27a has a shape that extends the flange body part 220a upward and constitutes a part of the flange body part 220a. The extended flange part 27a has a predetermined thickness along the X-axis and has a surface substantially parallel to the YZ plane.

[0090] A notch 28a is formed between the respective protection hook portions 23a and 24a. The lead portions 43a1 and 43a2 of the wire 41a shown in FIG. 2 can be inserted into the notch 28a. Also, the lead portion 43a1 shown in FIG. 2 can be inserted between the core separation wall 25a and the protection hook portion 23a. Further, the lead portion 43a2 can be inserted between the core separation wall 26a and the protection hook portion 24a.

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

[0092] As shown in FIG. 5A, above the flange portion main body 220b, protection hook portions 23b and 24b are formed side by side along the Y-axis. The protection hook portions 23b and 24b are connected above the flange portion main body 220b via protection hook holding portions 23b1 and 24b1. Core separation walls 25b and 26b are formed in the protection hook holding portions 23b1 and 24b1. The core separation walls 25b and 26b protrude outward along the X-axis and face the protection hook portions 23b and 24b.

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

[0094] A notch 28b is formed between the respective protection hook portions 23b and 24b. The lead portions 43b1 and 43b2 of the wire 41b (Fig. 2) can be inserted into the notch 28b. Also, the lead portion 43b1 can be inserted between the core separation wall 25b and the protection hook portion 23b. Further, the lead portion 43b2 can be inserted between the core separation wall 26b and the protection hook portion 24b.

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

[0096] As shown in Fig. 6A, the case 90 is formed by bending a single plate-like member such as a metal excellent in heat dissipation such as aluminum. The case 90 is composed of a plate-like member constituting the lower bottom surface 90b along the Z-axis, plate-like members constituting the side surfaces 90c and 90c on both sides along the X-axis, and plate-like members constituting the side surfaces 90d and 90d on both sides along the Y-axis. The upper side along the Z-axis is an upper opening 90a. There is a gap between the plate-like members on the side surface 90c, and there is also a gap between the plate-like members between the side surface 90c and the bottom surface 90b.

[0097] The case 90 has a terminal block support portion 91. The terminal block support portion 91 is disposed on the upper side along the Z-axis of one of the side surfaces 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 is formed with support through holes 92a, 92b, 93a, 93b, engagement holes 94a, 94b, and a central hole 95.

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

[0099] As shown in FIG. 2, the terminal block 70 is formed separately from the bobbin 20 and is attached to the upper side along the Z-axis of the terminal block support portion 91 via the insulation securing member 80. The terminal block 70 may be composed of the same insulating member as the bobbin 20, but is preferably composed of an insulating member having better moldability (or heat resistance or insulation). Further, the insulation securing member 80 may be composed of the same insulating member as the bobbin 20, but is preferably composed of an insulating member having better insulation. Note that the bobbin 20 is composed of, for example, plastics such as PPS, PET, PBT, LCP, or other insulating members (preferably materials having heat resistance).

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

[0101] The fasteners 78a, 78b, 79a, 79b may be integrally formed 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, 79b. The fastener arrangement holes 71a, 71b, 72a, 72b penetrate from the upper surface along the Z-axis to the lower side along the Z-axis of the terminal block base portion 701.

[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 from the upper surface along the Z-axis of the terminal block base portion 701 downward along the Z-axis. By inserting the mounting claws of the terminals described later into the mounting claw holes 73a1 to 73a4, 73b1 to 73b4, 74a1 to 74a4, and 74b1 to 74b4, the terminals and the terminal block 70 can be fixed.

[0103] As shown in FIG. 9A, in this embodiment, on the inner surface along the Y-axis of the terminal block base portion 701, a terminal separation wall fitting groove 77 is formed along the Z-axis. The terminal separation wall fitting groove 77 is formed so that the terminal separation wall 87 can fit therein. Also, at the middle of the fastener placement holes 72a and 72b and on the outer surface along the Y-axis of the terminal block base portion 701, an engagement notch 76 is formed. By engaging the engagement claws 861 of the middle engagement portion 86 of the insulation securing member 80 with the engagement notch 76, the terminal block 70 and the insulation securing member 80 can be fixed.

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

[0105] The engagement protrusions 75a and 75b are inserted into the middle through holes 85a and 85b of the insulation securing member 80 shown in FIG. 9B and the support through holes 94a and 94b of the terminal block support portion 91 shown in FIG. 6A, and are caught on the lower surface along the Z-axis of the terminal block support portion 91 as shown in FIG. 4B. In this way, the terminal block 70, the insulation securing member 80, and the terminal block support portion 91 can be fixed.

[0106] As shown in FIG. 2, the insulation ensuring member 80 has an intermediate portion 82 disposed between the terminal block 70 and the terminal block support portion 91, and an insulation sheet portion 81 disposed 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 insulation sheet portion 81 are integrally formed into a thin sheet along a plane perpendicular to the Z axis. The intermediate portion 82 is connected to the outside along the Y axis of the insulation sheet portion 81.

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

[0108] As described above, intermediate through holes 85a, 85b through which the engaging convex portions 75a, 75b of the terminal block 70 can be inserted are formed in the intermediate portion 82 of the insulation ensuring member 80 shown in FIG. 9A. 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 FIG. 9A, as shown in FIG. 9B, a central convex portion 88 protruding downward along the Z axis is integrally formed at the central position along the X axis on the lower surface of the intermediate portion 82. As shown in FIG. 4, the central convex portion 88 of the insulation ensuring member 80 is inserted into the central hole 95 of the terminal block support portion 91, and the insulation ensuring member 80 and the case 90 are positioned.

[0110] As shown in FIG. 9B, intermediate convex portions 83a, 83b, 84a, 84b are formed in the intermediate portion 82 of the insulation ensuring member 80. The intermediate convex portions 83a, 83a, 84a, 84b each protrude downward along the Z axis. Each of the intermediate convex portions 83a, 83b, 84a, 84b corresponds to the positions of the support through holes 92a, 92b, 93a, 93b of the terminal block support portion 91 shown in FIG. 4 and is formed side by side along the X axis.

[0111] The intermediate convex portions 83a, 83a, 84a, 84b of the insulation ensuring member 80 shown in FIG. 9B may be inserted into the support through-holes 92a, 92b, 93a, 93b shown in FIG. 6A to align the insulation ensuring member 80 with the terminal block support portion 91.

[0112] As shown in FIG. 9B, fixing protrusions 83a2, 83b2 whose outer diameter becomes smaller on the lower end side along the Z-axis may be formed on the outer peripheral surfaces of the intermediate convex portions 83a, 83b. By forming such intermediate convex portions 83a, 83b, it becomes easier to insert the intermediate convex portions 83a, 83a, 84a, 84b of the insulation ensuring member 80 into the corresponding support through-holes 92a, 92b, 93a, 93b while positioning them. Also, these connections become stronger.

[0113] As shown in FIG. 9A, accommodation recesses 83a1, 83b1, 84a1, 84b1 that are recessed downward and open upward along the Z-axis are formed in the intermediate convex portions 83a, 83a, 84a, 84b, respectively. The accommodation recesses 83a1, 83b1, 84a1, 84b1 correspond to the positions of the fastener arrangement holes 71a, 71b, 72a, 72b of the terminal block 70.

[0114] Each of the accommodation recesses 83a1, 83b1, 84a1, 84b1 is configured such that the threaded portion of a bolt for connecting an external terminal such as a circuit board (not shown) to the terminals 61a, 61b, 62a, 62b of the terminal block 70 can enter. Also, each of the accommodation recesses 83a1, 83b1, 84a1, 84b1 can accommodate metal dust and the like when screwing a bolt (not shown) to the fasteners 78a, 78b, 79a, 79b.

[0115] As shown in FIG. 1A, the terminal 61a has a terminal main portion 63a and a connecting wire portion 63a. Further, the terminal 61b has a terminal main portion 63b and a connecting wire portion 63b. Further, the terminal 62a has a terminal main portion 64a and a connecting wire portion 64a. Further, the terminal 62b has a terminal main portion 64b and a connecting wire portion 64b. Hereinafter, the configuration of the terminal 61a will be described, but the description of the terminal 61a also applies to the terminals 61b, 62a, and 62b. Therefore, unless particularly necessary, the description of the configurations of the terminals 61b, 62a, and 62b will be omitted.

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

[0117] The terminal main portion 63a shown in FIG. 1A is connected to the connecting wire portion 67a on the inner side along the Y-axis. The connecting wire portion 67a has a folded-back piece 67a1 and can be fixed with the lead portion sandwiched therebetween. As shown in FIG. 3, the connecting wire portion 67a is arranged at a position h2 lower than the terminal main portion 63a along the Z-axis. Further, the connecting wire portion 67a is arranged above the insulating sheet portion 81 along the Z-axis.

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

[0119] In the present embodiment, as shown in FIG. 1A, the terminal 61a is connected to the lead portion 43a1. Further, the terminal 61b is connected to the lead portion 43b1. Further, the terminal 62a is connected to the lead portion 43a2. Further, the terminal 62b is connected to the lead portion 43b2.

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

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

[0122] Next, the lead portions 43a1 (43a2, 43b1, 43b2) are sandwiched and temporarily fixed between the connecting portions 67a (67b, 68a, 68b) of the terminals 61a (61b, 62a, 62b) and the folded-back pieces 67a1 (67b1, 68a1, 68b1). Next, the connecting portions 67a (67b, 68a, 68b) are pressed with an electrode from above along the Z-axis, and the folded-back pieces 67a1 (67b1, 68a1, 68b1) are pressed with another electrode from below along the Z-axis, and a voltage is applied between the electrodes to electrically and mechanically connect the terminals 61a (61b, 62a, 62b) and the lead portions 43a1 (43a2, 43b1, 43b2) by fusing.

[0123] In this embodiment, during fusing, there are no components above and below the connecting portions 67a (67b, 68a, 68b) along the Z-axis, and the connecting portions 67a (67b, 68a, 68b) and the folded-back pieces 67a1 (67b1, 68a1, 68b1) can be pressed with electrodes from above and below.

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

[0125] Next, as shown in FIG. 2, the middle leg portions 53a and 53b of the cores 50a and 50b are inserted into the through holes 21 of the bobbin 20, and the bobbin 20 and the cores 50a and 50b are fixed, for example, with an adhesive or the like. Preferably, a thermosetting adhesive can be used as the adhesive.

[0126] Next, the bobbin 20 combined with the cores 50a and 50b is housed in a case 90 in which a potting resin (a resin having excellent heat dissipation) 210 has been previously injected (filled). At this time, as shown in FIG. 4, the insulation ensuring member 80 to which the terminal block 70 is attached is attached to the terminal block support portion 91. Note that after the bobbin 20 and the cores 50a and 50b are housed in the case 90, the potting resin may be injected from the opening 90a.

[0127] When attaching the insulation ensuring member 80 to which the terminal block 70 is attached to the terminal block support portion 91, the intermediate convex portions 83a (83b, 84a, 84b) are inserted into the support through holes 92a (92b, 93a, 93b). Also, the central convex portion 88 is inserted through the central hole 95. Further, the engaging convex portions 75a and 75b are inserted through the intermediate through holes 85a and 85b, and the claws formed on the engaging convex portions 75a and 75b are hooked on the terminal block support portion 91. In this way, the terminal block 70 and the insulation ensuring member 80 are fixed to the terminal block support portion 91.

[0128] After housing the bobbin 20 in the case 90, as shown in FIG. 2, the cover member 100 of the case 90 is bent to form the open cover portion 101 shown in FIG. 1A. By forming the open cover portion 101 in this way, it is not necessary to separately form and attach the cover member 100 to the case 90, and the assembly can be simplified.

[0129] In this embodiment, as shown in FIG. 2, in the coil device 10, the bobbin 20 is disposed inside the case 90 such that the winding axes C of the wires 41a and 41b are substantially parallel to the bottom surface 90b of the case 90. That is, the coil device 10 of this embodiment is a horizontal coil device and is also substantially parallel to the mounting surface of the coil device 10 or the mounting substrate (not shown). This coil device 10 can easily achieve a lower profile compared to a vertical coil device in which the winding axes of the wires 41a and 41b are substantially perpendicular to the bottom surface 90b of the case 90.

[0130] Also, as shown in FIG. 1A, in the coil device 10 of this embodiment, the terminal block 70 is supported on the 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 corresponding to the area of the terminal block 70, and the installation area of the case 90 can be reduced while being horizontal. Furthermore, compared with the case where the terminal blocks are provided on both sides along the X axis, it is also possible to reduce the installation area of the case along the X axis.

[0131] Furthermore, since the terminal block support portion 91 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 in the terminal block 70 of the coil device 10 to a substrate (not shown) disposed on the coil device 10, the terminal block support portion 91 facilitates connection to the substrate and improves reliability in order to reinforce the strength of the terminal block 70.

[0132] Also, in this embodiment, as shown in FIG. 2, a plurality of terminals 61a, 62a, 61b, and 62b are disposed on the terminal block 70 substantially parallel to the winding shaft C of the wires 41a and 41b. By configuring in this way, it becomes 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 row or multiple rows along the opening edge 96 of the case 90, and connection of each terminal to the substrate also becomes easy.

[0133] Also, as shown in FIG. 10, by filling the inside of the case 90 with a heat-dissipating resin (potting resin 210) or the like, heat from the wires 42, 44 or the bobbin 20 (including the cores 50a, 50b) can be dissipated to the bottom surface of the case 90 via the potting resin 210, improving the heat dissipation performance. Note that a cooling mechanism or the like is disposed on the bottom surface of the case 90.

[0134] Also, as shown in FIG. 1A, since the terminal block 70 is supported on the terminal block support portion 91 that protrudes outward from the opening edge 96 of the upper opening 90a of the case 90, at least most of the bobbin 20 (including the wire and the core) including the winding shafts of the wires 41a, 41b can be brought into contact with the potting resin 210 inside the case 90 without the terminal block 70 getting in the way. Therefore, the heat dissipation performance can be effectively enhanced with a minimum amount of necessary potting resin.

[0135] In the present embodiment, as shown in FIG. 6A, position adjusting portions 97a, 97b may be formed on the side surface 90d of the case 90. As shown in FIG. 10, the position adjusting portion 97a (97b) protrudes inward along the Y-axis inside the case 90.

[0136] When the bobbin 20 and the cores 50a, 50b are housed in the case 90, the elastic force of the lead portions of the wires or the like may act to press them against the side surface 90d of the case 90 on the side opposite to the terminal block 70 along the Y-axis. By the position adjusting portion 97a (97b) abutting against the outer leg portions 52a (52b) of the core 50a (50b), a gap can be formed for the potting resin 210 to enter between the side surface 90d and the core 50a.

[0137] Furthermore, as shown in FIG. 1A, in the coil device 10 of the present embodiment, a terminal block 70 is attached onto a terminal block support portion 91 via an insulation ensuring member 80. Therefore, after winding wires 41a and 41b around the bobbin 20 and attaching terminals 61a, 61b, 62a, and 62b to the terminal block 70, the operation of connecting the lead portions 43a1, 43a2, 43b1, and 43b2 of the wires 41a and 41b to the terminals 61a, 61b, 62a, and 62b at once becomes easy. 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 is appropriately performed using, for example, thermocompression bonding such as crimping.

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

[0139] Also, after connecting the lead portions 43a1, 43a2, 43b1, and 43b2 of the wires 41a and 41b to the terminals 61a, 61b, 62a, and 62b, the insulation ensuring member 80 is disposed on one side of the joint portions 67a, 67b, 68a, and 68b of the wires 41a and 41b. Therefore, the insulation between the joint portions 67a, 67b, 68a, and 68b and the cores 50a and 50b attached to the bobbin 20 can be effectively ensured.

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

[0141] As shown in FIG. 3, in the present embodiment, the insulation ensuring member 80 has an insulation sheet portion 81. The insulation sheet portion 81 is disposed between the connection portions 67a, 67b, 68a, 68b of the lead portions 43a1, 43a2, 43b1, 43b2 of the wires 41a, 41b and the terminals 61a, 61b, 62a, 62b, and the cores 50a, 50b attached to the bobbin 20.

[0142] By configuring in this way, the insulation ensuring member 80 can enhance the insulation between the connection portions 62b, 63b, 65b, 66 of the lead portions 43a1, 43a2, 43b1, 43b2 and the terminals 61a, 61b, 62a, 62b, and the outer leg portions 52a, 52b of the cores 50a, 50b attached to the bobbin 20. Also, the insulation ensuring member 80 can improve the insulation between the connection portions 67a, 67b, 68a, 68b of the lead portions 43a1, 43a2, 43b1, 43b2 and the terminals 61a, 61b, 62a, 62b and the case 90.

[0143] As shown in FIG. 3, in the present embodiment, the insulation ensuring member 80 has an intermediate portion 82 integrally formed with the insulation sheet portion 81. The intermediate portion 82 is sandwiched between the terminal block support portion 91 and the terminal block 70. As shown in FIG. 9A, the insulation ensuring member 80 has an intermediate engaging portion 86 that engages with the terminal block 70, and the intermediate engaging portion 86 has engaging claws 861. By the intermediate engaging portion 86 engaging with the terminal block 70, it becomes easy to attach the terminal block 70 and the insulation ensuring member 80 while positioning them. Also, the terminal block 70 and the insulation ensuring member 80 can be fixed without using an adhesive. However, an adhesive may be used.

[0144] As shown in FIG. 4, in the present embodiment, the intermediate portion 82 has intermediate convex portions 83a, 83b, 84a, 84b that enter the support through holes 92a, 92b, 93a, 93b formed in the terminal block support portion 91. By the intermediate convex portions 83a, 83b, 84a, 84b entering the support through holes 92a, 92b, 93a, 93b, it becomes easy to position the insulation ensuring member 80 and the terminal block support portion 91.

[0145] As shown in FIG. 9A, the intermediate convex portions 83a, 83b, 84a, 84b have accommodation recesses 83a1, 83b1, 84a1, 84b1 that open toward the terminal block 70. The accommodation recesses 83a1, 83b1, 84a1, 84b1 can accommodate metal dust and the like when screws for mechanically and electrically connecting the terminals 61a, 61b, 62a, 62b and a substrate or the like are screw-coupled. The accommodation recesses 83a1, 83b1, 84a1, 84b1 are configured such that screw portions for attaching external terminals of a circuit board (not shown) or the like to the terminals 61a, 61b, 62a, 62b of the terminal block can enter.

[0146] As shown in FIG. 4, the terminal block 70 has engagement convex portions 75a, 75b. Further, as shown in FIG. 9A, intermediate through-holes 85a, 85b are formed in an intermediate portion 82 of the insulation ensuring member 80. As shown in FIG. 4, the engagement convex portions 75a, 75b engage with engagement holes 94a, 94b formed in the terminal block support portion 91 through the intermediate through-holes in the intermediate portion.

[0147] By configuring in this way, the positioning between the terminal block 70 and the insulation ensuring member 80 is achieved, and the attachment while positioning between the terminal block 70 and the terminal block support portion 91 becomes easy. Further, without using an adhesive, the terminal block 70, the insulation ensuring member 80, and the terminal block support portion can be fixed. However, an adhesive may be used.

[0148] As shown in FIG. 1A, the case 90 is provided with a cover member 100. The opening cover portion 101 of the cover member 100 covers at least a part of the upper opening 90a of the case 90 with a predetermined gap H1 shown in FIG. 3. The predetermined gap H1 is larger than the protruding height of the protruding portion 33 of the bobbin 20 from the upper opening 90a of the case 90 and larger than the protruding height of the protection hook portions 23a, 23b, 24a, 24b.

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

[0150] As shown in FIG. 3, in the present embodiment, the cover member 100 covers at least a part of the wire 44(41) wound around the bobbin 20 housed inside the case 90. The cover member 100 preferably covers the entire winding part of the wires 41a, 41b except for the lead parts 45, 46(42, 43) of the wire. By forming the cover member 100 of metal or the like, the effect of shielding the leakage magnetic flux from the winding part (coil part) of the wires 41a, 41b is improved.

[0151] As shown in FIG. 3, in the present embodiment, the cover member 100 is integrally formed with the case 90. By integrally forming the cover member 100 and the case 90 by bending a metal plate or the like, the manufacturing of the cover member 100 and the case 90 becomes easy. Also, in the present embodiment, the terminal block support part 91 is integrally formed with the case 90. By integrally forming the terminal block support part 91 and the case 90 by bending a metal plate or the like, the manufacturing of the terminal block support part 91 and the case 90 becomes easy.

[0152] As shown in FIG. 5A, in the present embodiment, the bobbin 20 has a winding core part 21 around which the wire is wound and flange parts 22a, 22b attached to the ends of the winding core part 21. Also, the flange parts 22a, 22b have protection hook parts 23a, 23b, 24a, 24b.

[0153] The protection hook portions 23a, 23b, 24a, and 24b project upward from the upper opening 90a of the case 90, and as shown in FIG. 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 on the protection hook portions 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 mounted on the terminal block 70.

[0154] As shown in FIG. 3, in the present embodiment, the protection hook portions 23a, 23b, 24a, and 24b have a height h1 that is flush with or higher than the upper surface of the terminals 61a, 61b, 62a, and 62b. Further, the wire connection 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 and 41b are connected are arranged at a position lower by a height h2 than the upper surface of the terminals. By arranging in this way, the protection hook portions 23a, 23b, 24a, and 24b can effectively protect the wire connection portions 67a, 67b, 68a, and 68b, and can effectively prevent a protruding portion from a substrate (not shown) or the substrate itself from contacting the wire connection portions 67a, 67b, 68a, and 68b.

[0155] Also, in the present embodiment, the opening cover portion 101 is located at a position H1 higher than the opening 90a of the case 90, and the protection hook portions 23a, 23b, 24a, and 24b are arranged between the opening cover portion 101 and the opening 90a. By arranging in this way, the opening cover portion 101, together with the protection hook portions 23a, 23b, 24a, and 24b, can protect the wire connection portions 67a, 67b, 68a, and 68b, and can effectively prevent a protruding portion from a substrate or the substrate itself from contacting the wire connection portions 67a, 67b, 68a, and 68b.

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

[0157] Also in the present embodiment, since the middle legs 53a (53b) of the cores 50a (50b) have the above-described relationship, it is possible to further reduce the height and size while improving the heat dissipation compared to a coil device having a core with a normal middle leg shape (where the upper half and the lower half are the same).

[0158] Inside the case 90, a heat-dissipating resin such as potting resin is filled to cool the cores 50a (50b) and the wires 41a, 41b mounted on the bobbin 20. However, the height of the case 90 is regulated to the minimum necessary from the perspective of reducing the height. Therefore, as shown in FIG. 7, the liquid level S of the heat-dissipating resin accommodated inside the case 90 must be lower than the upper horizontal plane P1 including the upper end E1 of the middle legs 53a (53b) of the cores 50a (50b). Therefore, a part of the upper end of the core including the upper end E1 of the middle legs 53a (53b) of the cores 50a (50b) (including the coil, and the same applies hereinafter) will not come into contact with the heat-dissipating resin.

[0159] In the coil device 10 according to the present invention, due to having the above-described configuration, the cross-sectional area, volume, and / or the area of the outer peripheral surface of the cores 50a (50b) of the part that does not contact the heat-dissipating resin can be minimized. Also, the cross-sectional area, volume, and / or the area of the outer peripheral surface of the cores 50a (50b) of the part that contacts the heat-dissipating resin can be minimized. Therefore, in the coil device 10 according to the present embodiment, it is possible to further reduce the height and size while improving the heat dissipation compared to a coil device having a core with a normal middle leg shape (where the upper half and the lower half are the same).

[0160] Also, in the present embodiment, as shown in FIG. 7, the outer leg upper surface 522a (522b) which is the upper end of the outer leg portion 52a (52b) and the upper end E1 of the middle leg portion 53a (53b) have substantially the same height. By adopting such a configuration, the balance of the magnetic flux is improved and the characteristics are enhanced.

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

[0162] Also, as shown in FIG. 7, in the present embodiment, a lower concave portion (notch) 55a (55b) is formed in the base portion 51a (51b) located below the middle leg portion 53a (53b). Through the concave portion 55a (55b), near the bottom 90b of the case 90, a heat-dissipating resin such as potting resin can easily enter the central portion in the axial direction of the core 50a (50b), improving the heat dissipation performance.

[0163] Also, in the present embodiment, similar to the middle leg portion 53a (53b), the outer leg portion 52a (52b) can be made lower-profile and smaller in size while improving heat dissipation by making the volume of the lower half OL2 of the outer leg larger than the volume of the upper half OL1 of the outer leg. Also, the balance of the magnetic flux is improved and the characteristics are enhanced.

[0164] Second Embodiment As shown in FIGS. 1B, 6B, and 6C, the coil device 20 according to the present embodiment is the same as the coil device 10 of the first embodiment except that the structures of the case 190 and the cover member 200 are different, and similar operational effects can be expected. In the following description, the description of the parts common to the first embodiment will be omitted.

[0165] As shown in FIGS. 6B and 6C, in the present embodiment, the case 190 and the cover member 200 are each formed separately from a metal plate or the like and assembled as shown in FIG. 1B.

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

[0167] As shown in FIG. 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 and 203. The side cover portion 202 is formed so as to protrude downward along the Z-axis from one end along the Y-axis of the opening cover portion 201. As shown in FIG. 1B, the side cover portion 202 has an outer surface 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 may be recessed inwardly from the side surface 90d, or may protrude slightly.

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

[0169] In each cover support portion 203, a locking piece 204 having an engaging convex portion formed at the tip is formed so as to extend upward along the Z-axis in a reverse U-shaped groove. The engaging convex portion is formed by bending the upper tip of the locking piece 204 so as to protrude outward along the X-axis. The cover support portions 203 located on the upper side along the Z-axis and both sides along the Y-axis of the locking piece 204 are cut out to form a reverse U-shaped groove.

[0170] With such a configuration, the locking piece 204 is held in a cantilever support beam shape with respect to the main portion of the cover support portion 203 and can be elastically deformed by bending, and the engaging convex portion can be elastically moved 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 convex portion of the locking piece 204 shown in FIG. 6C can be easily engaged with the locking hole 198a (198b), and the cover member 200 and the case 190 can be connected.

[0171] Further, each cover support portion 203 has a wide portion with openings 206 penetrating through the front and back surfaces formed on both sides along the Y-axis of an inverted U-shaped groove penetrating through the front and back surfaces thereof. A cover placement portion 205 is formed below along the Z-axis of the wide portion of each cover support portion 203, and a notch recessed upward from the bottom is formed at a substantially central portion along the Y-axis of the cover placement portion 205.

[0172] Including this notch, the openings 206 and the U-shaped groove also serve as passageways for the potting resin filled inside the case 190, and the inside of the case 190 can be easily filled with the potting resin. In the coil device 20 of the present embodiment, since the cover member 200 and the case 190 are separated, when accommodating a bobbin or the like around which a coil is wound inside the case 190, the cover member does not get in the way, and the operation of bending and forming the cover member with respect to the case is also no longer necessary.

[0173] Third Embodiment As shown in FIG. 11, the coil device according to the present embodiment has a bobbin 120, terminals 161a, 162a, 161b, 162b, a terminal block 170, and an insulating cover 180 as necessary, 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 the parts common to the first embodiment is omitted.

[0174] As shown in FIG. 11, the bobbin 120 has terminal block fixing portions 123a (123b) above along the Z-axis of each flange portion 122a, 122b located on both sides. Engagement recesses 124a (124b) are formed further above along the Z-axis of the terminal block fixing portions 123a (123b). Further, fixing protrusions 130a (130b) are formed on the terminal block fixing portions 123a (123b).

[0175] Also, at both ends of the terminal block 170 along the X-axis, there are provided arm portions 172a (172b) having hook portions 173a (173b) that fit into the engagement recesses 124a (124b). Further, the terminal block 170 is formed with fixing recesses 175a (175b) having a shape corresponding to the fixing protrusions 130a (130b). Also, at both ends of the terminal block 170 along the X-axis, there are formed step portions 174a (174b). The lower step surfaces 174a1 (174b1) of the step portions 174a (174b) are formed so as to support the lower surface of the terminal block fixing portion 123a (123b) along the Z-axis from below.

[0176] In this embodiment, the engagement recesses 124a (124b) and the arm portions 172a (172b) are fitted together, the fixing protrusions 130a (130b) and the fixing recesses 175a (175b) are combined, and the lower step surfaces 174a1 (174b1) support the lower surface of the terminal block fixing portion 123a (123b) along the Z-axis from below, whereby the terminal block 170 is fixed to the bobbin 120.

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

[0178] Also, in this embodiment, the terminal cover 180 is formed with a gripping portion 184. The upper arm 184a and the 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, whereby the terminal cover 180 is fixed to the terminal block 170.

[0179] By configuring in this way, it becomes easy to arrange the terminals 161a, 162a, 161b, 162b to which the lead portions of the plurality of wires wound around the bobbin core portion 121 of the bobbin 120 are connected in a straight line in one row or a plurality of rows along the opening edge of the case, and it also becomes easy to connect each terminal to the substrate.

[0180] In addition, the terminal block 170 can be arranged not only linearly along the X-axis on only 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 thereon may be arranged on one side, and a terminal block with the other two terminals arranged thereon may be arranged on the other side.

[0181] Note that the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the present invention.

[0182] For example, the heat-dissipating resin is not limited to the potting resin, and other resins with excellent heat dissipation may be used. The heat-dissipating resin is composed of, for example, a silicone resin, a urethane resin, an epoxy resin, etc. that are soft even after injection. The longitudinal elastic modulus of the resin is preferably 0.1 to 100 MPa, and the Shore A hardness is preferably 100 or less, more preferably 60 or less. Further, in order to enhance the heat dissipation, the resin may be filled with a filler having high thermal conductivity.

[0183] Furthermore, in the above-described first or second embodiment, as shown in FIG. 6A or FIG. 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 portion 90a of the case 90 or 190, but is not limited thereto. For example, a plurality of terminal block support portions 91 may be formed in the same manner as in the above-described embodiment at two or more locations on both sides in the Y-axis direction of the upper opening portion 90a of the case 90 or 190 shown in FIG. 6A or FIG. 6B, or at two or more locations on both sides in the X-axis direction of the upper opening portion 90a of the case 90 or 190. Alternatively, separately from the above-described terminal block support portion 91, another terminal block support portion may be formed at any position of the upper opening portion 90a of the case 90 or 190 facing outside the opening, and a plurality of terminal block support portions 91 may be formed in the same manner as in the above-described embodiment.

[0184] In any case, when forming a plurality of terminal block support portions on the case, correspondingly, a plurality of terminal blocks 70 and insulation ensuring members 80 as shown in FIG. 9A may also be prepared and attached to each terminal block support portion.

[0185] Furthermore, the cores 50a and 50b are not limited to E-shaped cores, and may be a combination of E-shaped cores, a combination of an E-shaped core and an I-shaped core, or a combination of cores of other shapes. In any case, at least one of the cores 50a and 50b has middle legs 53a and 53b that are inserted into the shaft holes 211 of the bobbin core portions 21 of at least the bobbins 20.

Explanation of Reference Numerals

[0186] 10…Coil device (transformer) 20, 120…Bobbin 21, 121, 122a, 122b…Bobbin core portion 211…Through hole 22a, 22b…Flange portion 220a, 220b…Flange body 23a, 23b, 24a, 24b…Protective hook portion 23a1, 23b1, 24a1, 24b1…Hook support portion 25a, 25b, 26a, 26b…Core separation wall 27a, 27b…Extended flange portion 28a, 28b…Notch 32a, 32b…Mounting portion 33, 34…Protrusion 35, 36…Through hole 37a, 37b…Concave bottom 123a, 123b…Terminal block fixing portion 124a, 124b…Engagement recess (terminal block engagement portion) 130a, 130b…Fixing protrusion 41a, 41b…Wire 42a, 42b…Coil portion 43a1, 43a2, 43b1, 43b2…Lead portion 50a, 50b…Core 51a, 51b…Base portion 510a, 510b…Outer surface 511a, 511b…Inner surface 512a, 512b…Upper surface 513a, 513b…Lower surface 52a, 52b…Outer leg Inner side of the outer leg 520a, 520b… End face of the outer leg 521a, 521b… Upper surface of the outer leg 522a, 522b… Lower surface of the outer leg 523a, 523b… Middle leg part 53a, 53b… End face of the middle leg 531a, 531b… Recess (notch) 55a, 55b… Inner peripheral surface 550a, 550b… Tapered surface 551a, 551b… Thick part 56a, 56b… Terminals 61a, 61b, 62a, 62b, 161a, 162a, 161b, 162b… Main part of the terminal 63a, 63b, 64a, 64b… Mounting claws 63a1~63a4, 63b1~63b4, 64a1~64a4, 64b1~64b4… Connection holes 65a, 65b, 66a, 66b… Wire connection part 67a, 67b, 68a, 68b… Folded-back pieces 67a1, 67b1, 68a1, 68b1… Main part of the terminal 163a, 164a, 163b, 164b… Wire connection part 167a, 168a, 167b, 168b… Terminal block 70, 170… Base part of the terminal block 701… Fastener placement holes 71a, 71b, 72a, 72b… Terminal fixing part 71a1, 71b1, 72a1, 72b1… Mounting claw holes 73a1~73a4, 73b1~73b4, 74a1~74a4, 74B1~74b4… Engaging convex part 75a, 75b… Notch for engagement 76… Fitting groove for the terminal separation wall 77… Fasteners 78a, 78b, 79a, 79b… Arm part (bobbin engaging part) 172a, 172b… Hook part (bobbin engaging part) 173a, 173b… Step part 174a, 174b… Lower step surface 174a1, 174b1… Fixing recess 175a, 175b… 178…Terminal cover mounting part 180…Terminal cover (insulation ensuring member) 181…Bottom of terminal cover 183a, 183b…Side parts of terminal cover 184…Gripping part 184a…Upper arm 184b…Lower arm 80…Insulation ensuring member 81…Insulating sheet part 82…Middle part 83a, 83b, 84a, 84b…Middle convex parts 83a1, 83b1, 84a1, 84b1…Receiving recesses 83a2, 83b2…Fixing protrusions 83a3, 83b3, 84a3, 84b3…Fastener placement parts 85a, 85b…Middle through-holes 86…Middle engaging part 861…Engaging claws 87…Terminal separation wall 88…Central convex part 90, 190…Case 90a…Upper opening 90b…Bottom surface 90c, 90d…Side surfaces 91…Terminal block support part 92a, 92b, 93a, 93b…Support through-holes 94a, 94b…Engaging holes 95…Central hole 96…Opening edge 97a, 97b…Position adjusting parts 198a, 198b…Locking holes 100, 200…Cover member 101, 201…Open cover part 102, 202…Side cover parts 203…Cover support part 204…Locking piece 205…Cover placement part 206…Opening 210…Potting resin

Claims

1. A bobbin having a core portion around which a wire is wound, a core having a middle leg portion inserted into the axial hole of the core portion, a case for housing the bobbin to which the core is attached, A coil device comprising: The bobbin is disposed 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 portion 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 shortest connects between the upper horizontal plane including the upper end of the middle leg portion and the lower horizontal plane including the lower end of the middle leg portion, The middle leg portion has a cross-sectional shape in which the cross-sectional area (CA2) of the lower half is larger than the cross-sectional area (CA1) of the upper half, The core A base portion to which the base end portion of the middle leg portion is connected, External leg portions connected to the base portion and disposed on both sides of the middle leg portion, The upper end of the external leg portion and the upper end of the middle leg portion have substantially the same height, The lower end of the middle leg portion is located above the lower end of the external leg portion, A notch is formed in the base portion located below the middle leg portion Coil device.

2. A bobbin having a core portion around which a wire is wound, a core having a middle leg portion inserted into the axial hole of the core portion, a case for housing the bobbin to which the core is attached, A coil device comprising: The bobbin is disposed 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 portion 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 shortest connects between the upper horizontal plane including the upper end of the middle leg portion and the lower horizontal plane including the lower end of the middle leg portion, The middle leg portion has a shape in which the volume (V2) of the lower half is larger than the volume (V1) of the upper half, The core A base portion to which the base end portion of the middle leg portion is connected, External leg portions connected to the base portion and disposed on both sides of the middle leg portion, The upper end of the external leg portion and the upper end of the middle leg portion have substantially the same height, The lower end of the middle leg portion is located above the lower end of the external leg portion, A notch is formed in the base portion located below the middle leg portion Coil device.

3. A bobbin having a core portion around which a wire is wound, a core having a middle leg portion inserted into the axial hole of the core portion, a case for housing the bobbin to which the core is attached, A coil device comprising: The bobbin is disposed 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 portion 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 shortest connects between the upper horizontal plane including the upper end of the middle leg portion and the lower horizontal plane including the lower end of the middle leg portion, the middle leg portion has a shape in which the area (OA2) of the outer peripheral surface of the lower half is larger than the area (OA1) of the outer peripheral surface of the upper half. The core has a base portion to which the base end portion of the middle leg portion is connected, and outer leg portions that are connected to the base portion and are disposed on both sides of the middle leg portion. The upper end of the outer leg portion and the upper end of the middle leg portion have substantially the same height. 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 middle 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 outer leg upper half and an outer leg lower half by the intermediate horizontal plane, the outer leg portion has a shape in which the volume (OV2) of the outer leg lower half is larger than the volume (OV1) of the outer leg upper half.

5. The coil device according to any one of claims 1 to 4, wherein the inside of the case can be filled with a heat-dissipating resin.

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

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

8. 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 7, wherein a terminal block is disposed on the terminal block support portion.

9. The coil device according to claim 8, wherein a plurality of terminals are disposed on the terminal block substantially parallel to the winding axis of the wire.

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