Coil device

Abstract

To provide a coil device which has an excellent heat discharge property and can be downsized.SOLUTION: The coil device includes: a core 2 having a magnetic body; wires 4, 5 wound around at least a part of the core 2; and a terminal board 7 for holding a terminal 6 to which lead parts 41a, 41b, 51a, 51b of the wires 4, 5 are connected. At least a part of the terminal board 7 is fixed to a part of the core 2.SELECTED DRAWING: Figure 2A

Description

[Technical field]

[0001] The present invention relates to a coil device used, for example, as a transformer. [Background technology]

[0002] Patent Document 1 discloses a coil device having a cylindrical bobbin, a wire wound portion arranged on the outer circumferential surface of the bobbin, and a core with a center leg portion attached to the bobbin. The center leg portion is inserted into a through hole of the bobbin and is arranged radially inside the wire wound portion. The bobbin is provided with a terminal block with a terminal attached thereto.

[0003] As shown in Patent Document 1, in conventional coil devices, a terminal block to which a terminal is attached is generally provided on a bobbin. Recently, there has been a demand for coil devices that have excellent heat dissipation properties and can be made compact. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2014-93404 A Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a coil device that has excellent heat dissipation properties and can be made compact. [Means for solving the problem]

[0006] In order to achieve the above object, a coil device according to one aspect of the present invention comprises: A core including a magnetic material; a wire wound around at least a portion of the core; A terminal block for holding a terminal to which a lead portion of the wire is connected, At least a portion of the terminal block is fixed to a portion of the core.

[0007] In the coil device according to one aspect of the present invention, since the terminal block is fixed to the core, it is not necessary to use a bobbin. Also, since it is not necessary to use a bobbin, it is possible to reduce the distance between the winding part of the wire and the core, and it is possible to reduce the size and weight of the coil device.

[0008] Furthermore, it is possible to directly cool the wire windings and core using heat dissipating resin without using a bobbin, improving heat dissipation and enabling the coil device to handle larger currents. Even in coil devices that use a case filled with heat dissipating resin, the case can be made smaller and heat dissipation is particularly improved.

[0009] When using a bobbin as in the past, it was necessary to provide a clearance between the core and the bobbin from the viewpoint of ease of assembly, etc., and the overall size of the coil device was inevitably large. In addition, the presence of the bobbin in the past limited the area where the heat dissipating resin came into direct contact with the coil and core.

[0010] Preferably, the terminal block is disposed in a position covering at least a portion of the upper surface of the core. By fixing the terminal block to the core in such a position, it is possible to reduce the size of the coil device and also to improve heat dissipation.

[0011] The wire may include at least a first wire and a second wire, the lead portion may include a plurality of lead portions, and the terminal may include a plurality of terminals. Preferably, the terminal block is provided with terminals to which the lead portions of the first wires are connected and terminals to which the lead portions of the second wires are connected. With this configuration, even if the number of terminals is large, it is easy to reduce the size of the coil device and improve heat dissipation.

[0012] The terminal block may be provided at one end of the core along a first axis that is substantially perpendicular to the winding axis of the wire. This configuration facilitates miniaturization of the coil device and improves heat dissipation.

[0013] The terminal block may have a terminal mounting portion having mounting grooves into which four or more of the terminals are respectively fitted. With this configuration, even if there are a large number of terminals, the terminals can be easily mounted, and the coil device can be easily miniaturized while improving heat dissipation.

[0014] The terminal block may further include a core cover portion that is continuous with the terminal mounting portion and covers a portion of the upper surface of the core different from the portion of the upper surface of the core that is covered by the terminal mounting portion. This configuration makes it easier to attach the terminal block to the upper surface of the core.

[0015] The core cover may have a through groove for passing a heat sink disposed in contact with the upper surface of the core. This configuration makes it easy to bring the heat sink into contact with the upper surface of the core, and makes it easy to dissipate heat from the upper surface of the core to the heat dissipating resin or the outside air through the heat sink.

[0016] The terminal block may have a first terminal mounting portion having mounting grooves into which terminals to be connected to the pair of lead portions of the first wire respectively fit, and a second terminal mounting portion having mounting grooves into which terminals to be connected to the pair of lead portions of the second wire respectively fit. Preferably, the first terminal mounting portion and the second terminal mounting portion are disposed on both ends of the core along a first axis that is substantially perpendicular to the winding axis of the wire.

[0017] With this configuration, even if there are a large number of terminals, it is possible to reduce the number of terminals to be attached to each terminal block attachment part, and for example, it becomes easy to align the positions of the terminals attached to each terminal block attachment part with the positions of the recesses formed in the core, etc. As a result, the coil device can be further miniaturized.

[0018] The first terminal mounting portion and the second terminal mounting portion may be provided separately, or may be integrally connected by an intermediate core cover portion. Preferably, the intermediate core cover portion covers a central portion of the upper surface of the core located between the first terminal mounting portion and the second terminal mounting portion. This configuration makes it easy to simultaneously position and mount the two terminal mounting portions on the upper surface of the core. This also contributes to the miniaturization of the coil device.

[0019] The intermediate core cover part may have a through groove for passing a heat sink placed in contact with the upper surface of the core. This configuration makes it easy to bring the heat sink into contact with the upper surface of the core, and makes it easy to dissipate heat from the upper surface of the core to the heat dissipating resin or the outside air through the heat sink.

[0020] The intermediate core cover part may have at least one of a through hole penetrating from the inner surface to the outer surface of the intermediate core cover part and an uneven portion formed on the outer surface. Forming the through hole and / or the uneven portion in the intermediate core cover part contributes to preventing warping of the terminal block including the core cover part, and also contributes to reducing the weight of the coil device and improving the cooling efficiency.

[0021] The terminal block may have a bent piece that fits into a recess formed on a side of the core. This configuration makes it easier to position and fix the terminal block to the core, and also makes it possible to reduce the size of the coil device and improve heat dissipation.

[0022] Preferably, the bent piece is integrated with the terminal block so that the connection portion of the terminal fits into the recess of the core. By configuring in this way, the coil device can be made smaller and its heat dissipation properties can be improved.

[0023] A partition plate may be interposed between one end of the winding portion of the wire in the winding axis direction and the core. The partition plate may be insulating, in which case insulation between the core and the winding portion of the wire is improved. The partition plate may be combined with a terminal block, and the base portion of the core may be sandwiched between the terminal block and the partition plate. The partition plate is preferably formed with a through hole through which the center leg of the core passes.

[0024] Preferably, the core has a center leg disposed around the wire windings, and may further have a side leg covering at least a portion of an outer periphery of the first wire winding or the second wire winding.

[0025] The device may further include a case for housing at least a part of the wound portion of the wire. Preferably, the inside of the case is filled with a heat dissipating resin up to a position where at least a part of the wound portion of the wire is immersed. [Brief description of the drawings]

[0026] [Figure 1] FIG. 1 is a schematic perspective view of a coil device according to an embodiment of the present invention. [Figure 2A] FIG. 2A is a schematic perspective view of the coil device shown in FIG. 1 with the case removed. [Figure 2B] FIG. 2B is a schematic exploded perspective view of the coil device shown in FIG. 2A. [Figure 2C] FIG. 2C is a schematic exploded perspective view of the terminal block shown in FIG. 2B. [Figure 2D] FIG. 2D is a perspective view of the coil body shown in FIG. 2B with a portion thereof omitted. [Diagram 3] FIG. 3 is a perspective view of the terminal block body shown in FIG. 2C, seen from a different angle. [Figure 4A1] FIG. 4A1 is a schematic cross-sectional view taken along line IVA-IVA of the coil device shown in FIG. [Figure 4A2] 4A2 is a schematic perspective sectional view taken along line IVA-IVA of the coil device shown in FIG. [Figure 4B]FIG. 4B is a schematic cross-sectional view taken along line IVB-IVB of the coil device shown in FIG. 4A1. [Diagram 5] FIG. 5 is a schematic perspective view showing a flow direction of the heat dissipating resin in the spacer shown in FIG. 4A2. [Figure 6] FIG. 6 is a schematic perspective view of the spacer shown in FIG. 4A2. [Figure 7] FIG. 7 is a schematic perspective view of a coil device according to another embodiment of the present invention. [Figure 8] FIG. 8 is a schematic perspective view of the coil device shown in FIG. 7 with the terminal cover removed. [Figure 9] FIG. 9 is a schematic exploded perspective view of the coil device shown in FIG. [Figure 10] FIG. 10 is a schematic exploded perspective view showing the relationship between the terminal block and the partition plate shown in FIG. [Figure 11] FIG. 11 is a schematic perspective view of a coil device according to still another embodiment of the present invention. [Figure 12] FIG. 12 is a schematic exploded perspective view of the coil device shown in FIG. [Figure 13] FIG. 13 is a perspective view of the coil device shown in FIG. 11 with the core and the heat dissipation cover removed. [Figure 14] FIG. 14 is an exploded perspective view of the coil device shown in FIG. 13 with the terminal cover removed. [Figure 15] FIG. 15 is an exploded perspective view of the coil device shown in FIG. 14, seen from a different angle. [Figure 16] FIG. 16 is a perspective view of the coil device shown in FIG. 11 with the terminal block removed and the terminal cover omitted. [Figure 17] FIG. 17 is an exploded perspective view of a core and a heat sink used in a coil device according to still another embodiment of the present invention. [Figure 18] FIG. 18 is an exploded perspective view of a core and a heat sink used in a coil device according to still another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the contents shown in the drawings are merely schematic and illustrative for understanding the present invention, and the appearance and dimensional ratios may differ from the actual product. In addition, the present invention is not limited to the following embodiment.

[0028] (First embodiment) A coil device 1 according to an embodiment of the present invention shown in Fig. 1 functions as, for example, a leakage transformer and is used in a power supply circuit of an in-vehicle charger or various electric devices. The coil device 1 has a core 2, a first wire 4, a second wire 5, a terminal block 7, and a case 8. In the drawings, the X-axis, Y-axis, and Z-axis are perpendicular to each other, and the Z-axis is parallel to the height direction of the coil device 1 (the winding axis direction of the coil). In the following description, for each of the X-axis, Y-axis, and Z-axis, the direction toward the center of the coil device 1 is referred to as the inside, and the direction away from the center of the coil device 1 is referred to as the outside.

[0029] As shown in Fig. 2A, the coil core assembly 3 has a core 2, a first wire 4, a second wire 5, and a terminal block 7 equipped with a terminal 6. Note that the heat sink 9 shown in Fig. 1 is omitted in Fig. 2. As shown in Fig. 2B, in this embodiment, the core 2 can be disassembled into a first core 21 arranged on the lower side along the Z axis, and a second core 22 arranged on the upper side of the first core 21 along the Z axis.

[0030] In this embodiment, the first core 21 and the second core 22 are each an E-shaped core having a substantially E-shape in a cross section parallel to a plane including the Z-axis and the Y-axis, and have the same shape, but may be different from each other. For example, one core may be an E-shaped core and the other core may be an I-shaped core. Also, in this embodiment, the core 2 is configured by combining two-piece cores 21 and 22, but it is not limited to being divided into two, and may be configured by a combination of cores divided into three or four or more parts.

[0031] In this embodiment, the first core 21 has a base portion 21a having a bottom surface parallel to a plane including the X-axis and the Y-axis, a middle leg portion 21b extending upward from the center of the base portion 21a along the Z-axis, and a pair of side legs 21b extending upward from both ends of the base portion 21a along the Y-axis along the Z-axis. The second core 22 has a base portion 22a having an upper surface parallel to the plane including the X-axis and the Y-axis, a middle leg portion 22b extending downward from the center of the base portion 22a along the Z-axis along the Z-axis, and a pair of side legs 21b extending downward from both ends of the base portion 22a along the Y-axis along the Z-axis along the Z-axis.

[0032] These cores 21 and 22 are not particularly limited as long as they are cores having a magnetic material, and may be made of, for example, ferrite, a metal magnetic material, or a resin containing magnetic powder. In this embodiment, as shown in FIG. 5, the tip of center leg 21b and the tip of center leg 22b are butted against each other and in contact, and the tip 21c1 of side leg 21c and the tip 22c1 of side leg 22c are butted against each other and in contact. However, in another embodiment, the tip of center leg 21b and the tip of center leg 22b may not be in direct contact with each other, and a gap may be formed between them. The heat dissipating resin 82 shown in FIG. 1 may be inserted into the gap, or another member may be interposed.

[0033] The two cores 21, 22 may be integrated with an adhesive after the coil body 30 is attached therebetween, or may be integrated with a fixing tape or the like, or may be integrated by combining them. As the adhesive, a resin material with good thermal conductivity, such as heat dissipation grease, may be used.

[0034] As shown in FIG. 2B, in this embodiment, the coil core assembly 3 includes a core 2 having a first core 21 and a second core 22, a coil body 30, and a terminal block 7 having a terminal 6. The coil body 30 includes a first wire winding portion 40 in which the first wire 4 is wound in a coil shape, a second wire winding portion 50 in which the second wire 5 is wound in a coil shape, and a spacer 10 disposed between these winding portions. In this embodiment, the second wire winding portion 50 is disposed above the first wire winding portion 40 along the Z axis, but the opposite is also possible. In this embodiment, for example, the first wire winding portion 40 is a primary coil of a transformer, and the second wire winding portion 50 is a secondary coil of the transformer, but the opposite is also possible.

[0035] In this embodiment, the first wire 4 and the second wire 5 are each composed of a self-bonding conductive wire having a fusion layer and an insulating layer, and the type of the conductive wire is not particularly limited, and may be a conductive core wire such as a round wire, a rectangular wire, a twisted wire, a Litz wire, or a braided wire. The material of the fusion layer or insulating layer covering the core wire is not particularly limited, and examples thereof include polyurethane, polyamideimide, polyimide, and polyester. In this embodiment, the first winding part 40 around which the first wire 4 is wound and the second winding part 50 around which the second wire 5 is wound are each preferably formed into a coil shape in advance, and are preferably provided in the form of an air-core coil before being integrated with the spacer 10.

[0036] In this embodiment, both the first wire 4 and the second wire 5 are made of a self-bonding wire, but only one of them may be a self-bonding wire, or both may be made of other wires. At least one of the first wire winding portion 40 and the second wire winding portion 50 may be a flat coil. The wire diameters of the first wire 4 and the second wire 5 may be the same or different, and are not particularly limited, but are preferably within the range of 1.0 to 3.0 mm, for example.

[0037] Lead portions 41a, 41b are formed on both ends of the first wire 4 constituting the first wire winding portion 40, and the respective lead portions 41a, 41b are drawn out from the first winding portion 40 to the upper side along the Z axis and connected to the respective terminals 6, 6. Also, lead portions 51a, 51b are formed on both ends of the second wire 5 constituting the second wire winding portion 50, and the respective lead portions 51a, 51b are drawn out from the second winding portion 50 to the upper side along the Z axis and connected to the respective terminals 6, 6.

[0038] The terminals 6 to which the lead portions 41a, 41b, 51a, and 51b are connected are attached to a terminal block 7. The terminal block 7 has a terminal cover 70, and the terminal cover 70 is attached to the terminal block 7, so that the terminals 6 are fixed along the longitudinal direction of the terminal block 7 at a predetermined interval along the Y axis. The terminal block 7 and the terminal cover 70 are preferably made of an insulating material such as synthetic resin, and may be made of the same insulating material, or may be made of different insulating materials. In this embodiment, the terminal block 7 is directly fixed to the core 2. The means for directly fixing the terminal block 7 to the core 2 is not particularly limited, and examples of the means include adhesion, fusion, and tape fixing, and all fixing means other than fixing by a bobbin are included.

[0039] As shown in Fig. 2C, in this embodiment, the multiple terminals 6 each have the same shape and include a terminal base portion 60, a connection portion 61 provided at one end of the terminal base portion 60 along the X-axis, and an external connection portion 62 provided at the other end of the terminal base portion 60 along the X-axis. Any of the lead portions 41a, 41b, 51a, and 51b shown in Fig. 2B is connected to the connection portion 61 by crimping, thermocompression bonding, laser welding, soldering, or the like. The external connection portion 62 is a portion that is connected to an external connection terminal (not shown) or a terminal connection recess of a circuit board.

[0040] The terminal base portion 60 of each terminal 6 is mounted in a plurality of mounting grooves 71 provided at predetermined intervals along the Y-axis direction on the terminal block 7, and minute protrusions formed in the mounting grooves 71 fit into fitting holes in the terminal base 60, enabling thermocompression bonding. Note that the base portion 60 of the terminal 6 may be fixed in the mounting grooves 71 by other methods. Note that the terminal 6 can be formed, for example, by pressing a metal plate.

[0041] The terminal block 7 has a plate-shaped terminal mounting portion 72 with a mounting groove 71 formed on an outer surface 72c, a pair of flat plate pieces 73 extending downward along the Z-axis from both ends of the terminal mounting portion 72 along the Y-axis, and a bent piece 74 that is integrated and continuous between the pair of flat plate pieces. As shown in Fig. 3, the bent piece 74 of the terminal block 7 has an inner surface convex portion 74a shaped to match the surface of the concave portion 22a1 formed at the end along the X-axis of the base portion 22a of the second core 22 shown in Fig. 2B. In addition, the flat plate piece 73 has an inner surface 73a shaped to match the planar shape of the side end surface 22c2 along the X-axis of the side leg portion 22c of the second core 22 shown in Fig. 2B.

[0042] An inner surface 72a of the terminal mounting portion 72 of the terminal block 7 shown in Fig. 3 is attached to the upper surface of the base portion 22a of the second core 22 shown in Fig. 2B, and can be fixed, for example, by an adhesive. Also, an inner surface 74a of a bent piece 74 of the terminal block 7 shown in Fig. 3 fits into a recess 22a1 of the base portion 22a of the second core 22 shown in Fig. 2B, and an inner surface 73a of a flat piece 73 of the terminal block 7 shown in Fig. 3 can be closely attached to a side end surface 22c2 of a side leg portion 22c of the second core 22 shown in Fig. 2B. In this embodiment, the terminal block 7 can be directly fixed to the core 2 (specifically, the second core 22) without using a bobbin.

[0043] As shown in Fig. 2B, the terminal cover 70 attached to the terminal block 7 has gripping pieces 70a at both ends in the Y-axis direction, with claws 70b at their tips. The claws 70b engage with inner recesses 72b provided at both ends along the Y-axis of the terminal mounting portion 72 of the terminal block as shown in Fig. 3, allowing the terminal cover 70 to be fixed to the terminal block 7.

[0044] 1, the case 8 has a substantially rectangular bottom plate 80, and side plates 81 that rise upward along the Z axis from the four sides of the bottom plate 80 to form a bottomed storage space inside, and an upper opening is formed in the upper part along the Z axis. The case 8 is preferably made of a metal such as aluminum that has excellent thermal conductivity, but may also be made of resin.

[0045] The lower half or more of the coil core assembly 3 is housed inside the case 8, and the liquid level of the heat dissipating resin 82 filled inside the case 8 is preferably at a position where at least the lower half or more of the first wire winding portion 40 and the second wire winding portion 50 are filled with the heat dissipating resin 82. More preferably, the liquid level of the heat dissipating resin 82 filled inside the case 8 is at least at a position where the first wire winding portion 40 and the second wire winding portion 50 are filled with the heat dissipating resin 82.

[0046] The heat dissipating resin 82 is also called potting resin, and is made of silicone resin, urethane resin, epoxy resin, etc. that remain soft even after injection, and the longitudinal elastic modulus of the potting resin is preferably 0.1 to 100 MPa. In this embodiment, for example, heat generated in the first winding part 40, the second winding part 50, and the core 2 can be efficiently dissipated from the bottom of the case 8 to the outside through the heat dissipating resin 82 and the case 8, thereby improving the cooling efficiency of the coil device 1. The heat dissipating resin 82 may be filled in the case 8 in advance and then the core coil assembly 3 as shown in FIG. 2A is accommodated therein, or the heat dissipating resin 82 may be poured into the case 8 after the core coil assembly 3 as shown in FIG. 2A is accommodated in the case 8.

[0047] As shown in Fig. 2B, a spacer 10 is disposed between the first opposing end 42 of the first wire winding portion 40 and the second opposing end 52 of the second wire winding portion 50. As shown in Figs. 2D, 4A1, 4A2, 5 and 6, the spacer 10 has a predetermined thickness t1 (see Fig. 2D) along the winding axis (Z-axis) of the first wire winding portion 40 and the second wire winding portion. The predetermined thickness t1 is not particularly limited, but is, for example, 0.2 to 2.0 mm.

[0048] In this embodiment, the spacer 10 is preferably fixed to the first opposing end 42 of the first wire winding portion 40 and / or the second opposing end 52 of the second wire winding portion 50 by means of thermocompression, adhesion, or the like. Preferably, these are thermocompression-bonded in the axial direction by a thermocompression layer coated on the outer periphery of the wires 4 and 5 constituting the wire winding portions 40 and 50.

[0049] 5, the spacer 10 has a plurality of outer recesses 11 along the circumferential direction, which are recessed from the outer circumferential position of the spacer 10 toward the inner circumferential position of the spacer 10 and do not contact the first opposing end 42 of the first wound portion 40 and the second opposing end 52 of the second wound portion 50. The spacer 10 also has a plurality of inner recesses 12 along the circumferential direction, which are recessed from the inner circumferential position of the spacer 10 toward the outer circumferential position of the spacer 10 and do not contact the first opposing end 42 of the first wound portion 40 and the second opposing end 52 of the second wound portion 50.

[0050] In this embodiment, both the outer periphery and the inner periphery of the ring-shaped spacer 10 have a repeated concave-convex shape, and outer recesses 11 and inner recesses 12 are alternately provided along the circumferential direction. The number of repetitions of the outer recesses 11 or inner recesses 12 along the circumferential direction is not particularly limited, but is preferably about 3 to 20, and more preferably about 5 to 15.

[0051] The outer recess 11 and the inner recess 12 could have been grooves formed on the front or back surface of the spacer 10, but in this embodiment, they are notches formed alternately on the outer and inner peripheral portions of the ring-shaped plate-shaped spacer, and therefore penetrate both the front and back surfaces of the spacer 10.

[0052] Therefore, the outer recess 11 functions as an outer flow path that allows a fluid to flow (including the reverse flow) from the outside to the inside in the radial direction of the first opposing end 42 or the second opposing end 52, and also functions as an axial flow path that allows a fluid to flow (including the reverse flow) from the first opposing end 42 to the second opposing end 52. The inner recess 12 functions as an inner flow path that allows a fluid to flow (including the reverse flow) from the inside to the outside in the radial direction of the first opposing end 42 or the second opposing end 52, and also functions as an axial flow path that allows a fluid to flow (including the reverse flow) from the first opposing end 42 to the second opposing end 52.

[0053] In this embodiment, as shown in Fig. 2D, preferably, the width wo along the circumferential direction of the outer recess 11 is wider at the outer peripheral position than at the inner peripheral position, and preferably, the width wi along the circumferential direction of the inner recess 12 is wider at the inner peripheral position than at the outer peripheral position. Also, under the same radial position, it is preferable that the width wo along the circumferential direction of the outer recess 11 is wider than the width wi along the circumferential direction of the inner recess 12, but they may be the same or vice versa.

[0054] In this embodiment, the spacer 10 is formed into a ring shape that is continuous along the circumferential direction, but it does not necessarily have to be continuous, and there may be a discontinuous part (cut part) that penetrates the outer circumference and the inner circumference at one or more places in the circumferential direction. For example, in this embodiment, all the inner recesses 12 and the outer recesses 11 are continuous along the circumferential direction, but one or more of the inner recesses 12 or the outer recesses 11 may have a cut part that penetrates the outer circumference and the inner circumference.

[0055] 4A1, outer periphery 13, which has the greatest outer diameter along the radial direction of spacer 10, is designed to be close to the inner periphery of side leg 21C or 22c of core 2, and preferably protrudes outward from the outer periphery of wire winding portion 40 or 50, but does not have to protrude or may be flush. By having outer periphery 13 protrude outward from the outer periphery of wire winding portion 40 or 50, contact between wire winding portions 40 and 50 can be effectively suppressed.

[0056] 4A1, inner periphery 14, which has the smallest inner diameter along the radial direction of spacer 10, is designed to be close to the outer periphery of center leg 21b or 22b of core 2, and preferably protrudes inward from the inner periphery of wire winding portion 40 or 50, but does not have to protrude and may be flush. Inner periphery 14 may be in contact with the outer periphery of center leg 21b or 22b of core 2. In the case of contact, heat from center leg 21b or 22b of core 2 is easily transferred to the spacer, improving heat dissipation.

[0057] 4B, there may be a gap between the inner peripheral surface of the wire winding portion 40 or 50 and the outer peripheral surface of the center leg portion 21b or 22b of the core 2, or the inner peripheral surface may be in close contact with the outer peripheral surface of the center leg portion 21b or 22b of the core 2. When there is a gap, the heat dissipation resin 82 shown in FIG.

[0058] 2D, in the coil device 1 according to this embodiment, the spacer 10 having a predetermined thickness is disposed between the first wire winding portion 40 and the second wire winding portion 50, and therefore the distance between the first opposing end 42 of the first wire winding portion 40 and the second opposing end 52 of the second wire winding portion 50 can be controlled by the thickness t1 of the spacer 10. As a result, the leakage of the coil device 1 can be adjusted.

[0059] In addition, in the coil device 1 according to this embodiment, the spacer 10 having a predetermined thickness t1 has an outer recess 11 corresponding to the outer flow path and the axial flow path, and an inner flow path 12 corresponding to the inner flow path and the axial flow path.

[0060] 5, heat dissipating resin 82, which is a cooling fluid, can be drawn between first opposed ends 42 and second opposed ends 52 from the outside to the inside in the radial direction of winding portions 40 and 50 through outer recess 11. Also, inner recess 12 can draw heat dissipating resin 82 between first opposed ends 42 and second opposed ends 52 from the inside to the inside or from the outside to the inside in the radial direction of winding portions 40 and 50.

[0061] Furthermore, in this embodiment, as shown in Fig. 4B, the first opposing end 42 of the winding portion 40 and the second opposing end 52 of the winding portion 50 are formed with a spiral recess 45 or 55 that continues along the circumferential direction in accordance with the spiral shape of the wire 4 or 5 that constitutes the winding portion 40 or 50, respectively. As shown in Fig. 5, the heat dissipating resin 82 drawn into the inside of the winding portion 40 or 50 through the outer recess 11 can also flow into the inner recess 12 located adjacent in the circumferential direction through the spiral recess 45 or 55. Alternatively, conversely, it can flow from the inner recess 12 located adjacent in the circumferential direction to the outer recess 11 through the spiral recess 45 or 55.

[0062] Furthermore, the outer recess 11 and the inner recess 12 are also axial through holes that do not contact both the first opposing end 42 and the second opposing end 52, and therefore allow the heat dissipating resin to flow along the Z-axis direction. In this manner, the heat dissipating resin 82 shown in Fig. 1 can be introduced between the first opposing end 42 and the second opposing end 52, and heat is transferred from the inner periphery side of the winding parts 40 and 50, where heat is most likely to be trapped, to the case 8 via the spacer 10 and the heat dissipating resin 82 located in the recesses 11 and 12, improving the heat dissipation of the coil device 1.

[0063] In this embodiment, the outer recess 11 and the inner recess 12 formed in the spacer 10 also serve as a plurality of flow path forming regions from which the members constituting the spacer 10 have been removed and which do not come into contact with the first opposing end 42 of the winding portion 40 and the second opposing end 52 of the winding portion 50. Furthermore, these plurality of flow path forming regions are present at a plurality of positions along the circumferential direction of the spacer 10.

[0064] By providing the surface of the spacer 10 with flow path forming regions in a plurality of locations along the circumferential direction where no components constituting the spacer 10 are present, it becomes possible for the heat dissipating resin, which is a cooling fluid, to be introduced between the first opposed end 42 and the second opposed end 52 at a plurality of locations along the circumferential direction, further improving the heat dissipation of the coil device 1. Even if the flow path forming regions are formed at a plurality of locations along the circumferential direction, the spacer 10 has a predetermined thickness t1, so that the leakage adjustment of the coil device 1 is well maintained.

[0065] In addition, in this embodiment, as shown in FIG. 2D, the circumferential width of the outer recess 11 is wider at the outer circumferential position compared to the inner circumferential position, making it easier to draw the heat dissipating resin 82 between the first opposing end 42 and the second opposing end 52 from the outside to the inside in the radial direction of the winding portion 40 or 50.

[0066] 2D, the width of the inner recess 12 along the circumferential direction is wider at the inner circumferential position than at the outer circumferential position, which makes it easier to draw the heat dissipating resin 82 between the first opposing end 42 and the second opposing end 52 from the inside to the outside in the radial direction of the winding portion 40 or 50. Alternatively, the heat dissipating resin 82 can be drawn between the first opposing end 42 and the second opposing end 52 along the inner recess 12 from the outside to the inside in the radial direction of the winding portion 40 or 50, and the heat dissipating resin 82 can be stored at the inner circumferential position where the width of the inner recess 12 is wider, thereby improving heat dissipation from the inside of the winding portion 40 or 50 and the outer circumferential surface of the middle leg portion 21b or 22b of the core 2.

[0067] In this embodiment, the inner recess 12 and the outer recess 11 are arranged adjacent to each other along the circumferential direction, so that the heat dissipating resin can be drawn between the first opposing end 42 and the second opposing end 52 in both the radial direction of the winding portion 40 or 50 from the inside to the outside and from the outside to the inside, thereby further improving the heat dissipation. In addition, the heat dissipating resin 82 can also flow between the adjacent inner recess 12 and outer recess 11 through, for example, the spiral recess 45 or 55 formed in the first opposing end 42 or the second opposing end 52.

[0068] Further, in this embodiment, as shown in Fig. 2D, the width wo of the outer recess 11 along the circumferential direction is made wider than the width wi of the inner recess 11 along the circumferential direction. As shown in Fig. 4B, the middle leg parts 21b and 22b of the core 2 are arranged in close contact with the inner peripheral part 14 which is the central opening of the spacer 10, so that it is easier to make the flow of the heat dissipating resin 82 from the outside to the inside in the radial direction of the spacer 10 than the flow of the heat dissipating resin 82 from the inside to the outside in the radial direction of the spacer 10. Therefore, by making the width wo of the outer recess 11 along the circumferential direction wider than the width wi of the inner recess 12 along the circumferential direction, it becomes easier to draw the heat dissipating resin 82 between the first opposing end 42 and the second opposing end 52.

[0069] Furthermore, in this embodiment, at least one of the first wire 4 constituting the first wire winding portion 40 and the second wire 5 constituting the second wire winding portion 50 is made of a conductor coated with an insulating layer having at least a heat-sealing layer. This configuration makes it easier to join parts of the wires 4 or 5 that contact each other for each winding turn by heat fusion, making it easier to form an air-core coil in which the wires 4 or 5 are wound in a coil shape. In addition, by combining the first wire winding portion 40, the spacer 10, and the second wire winding portion 50 and thermocompressing them in the winding axis direction, it becomes easier to manufacture the coil body 30 in which the first wire winding portion 40, the spacer 10, and the second wire winding portion 50 are integrated.

[0070] In this embodiment, the spacer 10 may be made of an insulating material and / or a metal material. Examples of insulating materials include synthetic resin, ceramic, and glass. When the spacer 10 is made of an insulating material, the insulation between the first wire winding portion 40 and the second wire winding portion 50 is also improved. In particular, ceramics are less likely to deform even when used at high temperatures, making it easier to stabilize the coil characteristics regardless of temperature.

[0071] When the spacer 10 is made of a metal material, the heat transfer characteristics of the spacer 10 itself are improved, and the heat dissipation is further improved. When the spacer 10 is made of a metal material, the wires 4 and 5 are preferably wires coated with an insulating film. The spacer 10 may also be made of a composite member of a metal member and an insulating member. For example, the spacer 10 may be a member in which the surface of a metal plate is coated with an insulating member such as resin. Alternatively, the spacer 10 may be made of an insulating member with metal powder dispersed therein.

[0072] In particular, in this embodiment, as shown in Fig. 2A, there is no need to use a bobbin because the terminal block 7 is directly fixed to the upper surface of the second core 22. In addition, since there is no need to use a bobbin, it is possible to reduce the distance between the wire windings 40, 50 and the core 2 shown in Fig. 2B, making it possible to reduce the size and weight of the coil device 1.

[0073] Furthermore, it becomes possible to directly cool the wire windings 40, 50 and the core 2 using heat dissipation resin 82 or the like without going through the bobbin, improving heat dissipation and enabling the coil device 1 to handle larger currents. Even in the coil device 1 that uses a case 8 filled with heat dissipation resin 82, the case 8 can be made smaller, and heat dissipation is particularly improved.

[0074] When using a bobbin as in the past, it was necessary to provide a clearance between the core and the bobbin from the viewpoint of ease of assembly, etc., and the overall size of the coil device was inevitably large. In addition, the presence of the bobbin in the past limited the area where the heat dissipating resin came into direct contact with the coil and core.

[0075] 2A, the terminal block 7 is disposed in a position that covers at least a portion of the upper surface of the core 2. Fixing the terminal block 7 to the core 2 in such a position contributes to miniaturization of the coil device 1 and also contributes to improved heat dissipation.

[0076] 2B, terminals 6, 6 to which the lead portions 41a, 41b of the first wire 4 are connected, and terminals 6, 6 to which the lead portions 51a, 51b of the second wire 5 are connected are attached to the terminal block 7. With this configuration, even if the number of terminals 6 is large, it is easy to reduce the size of the coil device 1 and the heat dissipation performance is improved.

[0077] Furthermore, the terminal block 7 is provided at one end of the core 2 along the X-axis that is approximately perpendicular to the winding axis (Z-axis) of the wires 4 and 5. With this configuration, it becomes easy to reduce the size of the coil device 1 and also improves heat dissipation.

[0078] 2C, the terminal block 7 has a terminal mounting portion 72 having mounting grooves 71 into which four or more terminals 6 are respectively fitted. With this configuration, even if there are a large number of terminals 6, the terminals 6 can be easily mounted, the coil device 1 can be easily miniaturized, and heat dissipation is improved.

[0079] 3, the terminal block 7 has a bent piece 74 that fits into the recess 22a1 formed on the side of the second core 22 shown in FIG. 2B. This configuration makes it easy to position and fix the terminal block 7 to the core 2, and also reduces the size of the coil device 1 and improves heat dissipation.

[0080] Second embodiment As shown in Figures 7 to 10, the coil device 1A according to this embodiment differs from the coil device 1 of the above-mentioned embodiment only in the configuration and effects described below, and a description of the common configuration and effects will be omitted. Note that in Figures 7 to 10, common members to those shown in Figures 1 to 6 are given the same reference numerals, and a description of overlapping parts will be omitted.

[0081] As shown in Fig. 7, the terminal block 7A of this embodiment has a core cover portion 75. As shown in Fig. 8, the core cover portion 75 is provided continuous with the terminal mounting portion 72, and covers the upper surface of the core 2 at a position different from the part of the upper surface along the Z axis of the core 2 covered by the terminal mounting portion 72. A through groove 76 penetrating along the Y axis is formed on the inner surface of the core cover portion 75, and a top plate portion 90 of the heat sink 9 is inserted along this through groove 76. The top plate portion 90 of the heat sink 9 is disposed between the inner surface of the core cover portion 75 and the upper surface of the core 2 along the through groove 76 so as to contact the upper surface of the core 2.

[0082] Heat generated on the upper surface of the core 2 is transferred to a top plate portion 90 of the heat sink 9, and then transferred from the top plate portion 90 to a side plate portion 91 of the heat sink 9. The heat transferred to the side plate portion 91 is transferred to, for example, a heat dissipating resin 82 filled inside the case 8 shown in FIG.

[0083] 10, terminal block 7A has a terminal mounting portion 72 in which four or more terminal grooves 71 are arranged at predetermined intervals along the Y axis. Terminal block 7A has a pair of flat plate pieces 73 extending downward along the Z axis from both ends of terminal mounting portion 72 along the Y axis, and a bent piece 74 that is integrated and continuous between the pair of flat plate pieces 73, 73. Bent piece 74 of terminal block 7A has an inner surface convex portion 74a that matches the shape of a central concave portion 77a1 of a rising piece 77a provided at one end of ring-shaped partition plate 77 along the X axis.

[0084] The rising piece 77a of the partition plate 77 has an inner surface convex portion 77a2 shaped to match the surface of the concave portion 22a1 formed at the end along the X-axis of the base portion 22a of the second core 22 shown in Fig. 9. The flat plate piece 73 of the terminal block 7A shown in Fig. 10 has an inner surface shaped to match the planar shape of the side end surface 22c2 along the X-axis of the side leg portion 22c of the second core 22 shown in Fig. 9.

[0085] An elastic piece 74b is provided on both sides along the Y-axis of the bent piece 74 formed continuously with the flat plate piece 73. A notch is formed in a part of the bent piece 74 located on both sides of the elastic piece 74b, so that the elastic piece 74b can be elastically deformed. A fitting hole is formed in the elastic piece 74b, and a fitting protrusion 77b formed on the rising piece 77a of the partition plate 77 fits into the fitting hole, so that the bent piece 74 of the terminal block 7A and the rising piece 77a of the partition plate 77 can be positioned and fixed.

[0086] A flat piece 73 and a bent piece 74 having the same configuration as the flat piece 73 and the bent piece 74 provided at the bottom along the Z axis of the terminal mounting part 72 of the terminal block 7A are also provided at the end of the core cover part 75 opposite the terminal mounting part 72 along the X axis. Similarly, the other end of the partition plate 77 along the X axis is provided with a rising piece 77a having the aforementioned fitting protrusion 77b. These rising pieces 77a, 77a fit onto the outer surfaces of a pair of bent pieces 74, 74 formed on the terminal block 7A, and the terminal block 7A and the partition plate 77 are combined.

[0087] With the terminal block 7A and the partition plate 77 combined, a gap is formed between the plate-like portion consisting of the core cover portion 75 and the terminal mounting portion 72 and the partition plate 77, and the base portion 22a of the second core 22 shown in Fig. 9 is disposed in this gap. Also, a gap extending along the Y-axis is formed between the upper surface of the base portion 22a of the second core 22 and the through groove 76 of the core cover portion 75, and the top plate portion 90 of the heat sink 9 shown in Fig. 8 passes through this gap, allowing the top plate portion 90 of the heat sink 9 to radiate heat from the upper surface of the core 2 to the outside through the top plate portion 90 and the side plate portion 91.

[0088] 9, the partition plate 77 is disposed so as to contact the upper end along the Z-axis of the coil body 30, and the inner diameter of a through hole 77c formed in the partition plate 77 is approximately the same as or slightly larger than the inner diameter of the second wire winding portion 50, allowing the middle leg portion 22b of the second core 22 to pass through. The partition plate 77 is preferably made of an insulating material such as synthetic resin, for example, like the terminal block 7A, but is not necessarily required to be made of the same insulating material as the terminal block 7A.

[0089] In this embodiment, the terminal mounting portion 72 of the terminal block 7A shown in Fig. 8 is fixed to the upper surface of one end portion along the X-axis of the second core 22, and the end portion of the core cover portion 75 opposite the terminal mounting portion 72 along the X-axis is fixed to the upper surface of the other end portion along the X-axis of the second core 22. An adhesive or the like is used as a fixing means. In this embodiment as well, the terminal block 7A can be fixed directly to the core 2 (specifically, the second core 22) without using a bobbin.

[0090] In the coil device 1A of this embodiment, since the terminal block 7A has a core cover portion 75, the terminal block 7A is stably fixed to the upper surface of the core 2, and the fixing strength is also improved. In addition, since the core cover portion 75 has a through groove 76 for passing the heat sink 9, the heat dissipation of the core 2 is also ensured. Furthermore, since the present embodiment has a partition plate 77 that can be made of an insulating material, the insulation between the second core 22 and the coil body 30 is improved, and the insulation between the coil body 30 and each terminal 6 is also improved.

[0091] In this embodiment, the partition plate 77 is combined with the terminal block 7A, but this is not necessarily required. Also, the partition plate 77 may be used in the coil device 1 of the first embodiment described above. Other configurations and effects of this embodiment are similar to those of the first embodiment described above.

[0092] Third embodiment As shown in Figures 11 to 15, the coil device 1B according to this embodiment differs from the coil device 1 or 1A according to the above-described embodiment only in the configuration and effects described below, and a description of the common configuration and effects will be omitted. Note that in Figures 11 to 15, common reference numerals are used for members common to those shown in Figures 1 to 10, and a description of overlapping parts will be omitted.

[0093] As shown in Fig. 11, the terminal block 7B of this embodiment has a middle core cover portion 75a. As shown in Fig. 12, the middle core cover portion 75 is formed integrally with the terminal mounting portions 72, 72 between the terminal mounting portions 72, 72 provided at both ends along the X-axis of the terminal block 7B. The middle core cover portion 75a covers the center portion of the upper surface of the core 2B located between the two terminal mounting portions 72, 72. This terminal block 7B is made of an insulating material such as synthetic resin, similar to the terminal blocks 7 and 7A of the above-mentioned embodiments.

[0094] At least one of a through hole penetrating from the inner surface to the outer surface of the intermediate core cover part 75a and an uneven part (reinforcing rib) formed on the outer surface is formed in the intermediate core cover part 75a of the terminal block 7B. By forming the through hole and / or the uneven part in the intermediate core cover part 75a, it contributes to preventing warping of the terminal block 7B including the core cover part 75a, and also contributes to reducing the weight of the coil device 1B and improving the cooling efficiency.

[0095] The intermediate core cover portion 75a has a through groove 76 through which the top plate portion 90 of the heat sink 9, which is disposed in contact with the upper surface of the core 2B, passes. This configuration makes it easy to bring the heat sink 9 into contact with the upper surface of the core 2B, and makes it easy to release heat from the upper surface of the core 2B to the heat dissipating resin or the outside air through the heat sink 9.

[0096] 12, the core 2B of this embodiment is made of the same material as the core 2 of the above-mentioned embodiment, and is a two-part core with an E-shaped cross section, but has a slightly different shape. In this embodiment, the recesses formed on both sides of the base portion 22a of the second core 22B along the X-axis are a combination of a stepped recess 22a2 and an intermediate recess 22a3.

[0097] The intermediate recess 22a3 is formed in the center of the stepped recess 22a2 along the Y axis, and is recessed further inward than the stepped recess 22a2. The outer peripheral surface of the center leg 22b is exposed at the bottom of the intermediate recess 22a3. The stepped recess 22a2 is a flat surface recessed inward from the side end surface 22c2 along the X axis of the side leg 22c, and may be tapered relative to the side end surface 22c2 like the recess 22a1 described above, but in this embodiment, it is recessed approximately parallel.

[0098] The stepped recess 22a2 and the intermediate recess 22a3 are formed on both sides along the X-axis of the base portion 22a of the second core 22B. Similarly, the stepped recess 21a2 and the intermediate recess 21a3 are formed on both sides along the X-axis of the base portion 21a of the first core 21B.

[0099] 12, the terminal block 7B of the present embodiment has one terminal mounting portion 72 having a pair of mounting grooves 71, 71 into which the terminals 6, 6 to be connected to the pair of lead portions 41a, 41b of the first wire 4 are respectively fitted, and the other terminal mounting portion 62 having a pair of mounting grooves 61 into which the terminals 6, 6 to be connected to the pair of lead portions 51a, 51b of the second wire 5 are respectively fitted. The one terminal mounting portion 72 and the other terminal mounting portion 72 are located at both ends along the X-axis of the terminal block 7B, respectively.

[0100] A pair of mounting grooves 71, 71 formed in each terminal attachment portion 72 are formed corresponding to the stepped recesses 22a2 located on both sides of the intermediate recess 22a3 of the second core 22B. The surface of the stepped recess 22a2 of the second core 22B is covered by stepped bent pieces 74 provided on both ends of the terminal block 7B in the X-axis direction. As shown in Fig. 14, the connection portion 61 of the terminal 6 is disposed outside the stepped bent pieces 74.

[0101] As shown in Fig. 16, at both ends of the terminal block 7B along the X axis, at positions spaced apart along the Y axis by a predetermined distance, flat plate pieces 73 are formed extending downward from the terminal mounting portion 72 along the Z axis. The stepped bent pieces 74 are integrally formed so as to be recessed inward from the flat plate pieces 73. In this embodiment, a pair of notches parallel to the Z axis are formed at a predetermined interval in each flat plate piece 73, and a resiliently deformable mounting piece 73b is formed between the notches. The inner side of the mounting piece 73B can elastically contact the side end surface 22c2 of the second core 22B, making it easy to mount the terminal block 7B on the upper surface of the core 2B.

[0102] The inner surface of the stepped bent piece 74 provided on the opposite side of the terminal block 7b along the X-axis has a shape that matches the outer surface shape of the stepped recess 22a2 and the intermediate recess 22a3 of the second core 22B, and is adapted to fit into the stepped recess 22a2 and the intermediate recess 22a32. At approximately the center along the Y-axis of each terminal mounting part 72, a mounting protrusion 72d having an upper surface continuous with the upper surface of the mounting part 72 is integrally formed with the mounting part 72 so as to protrude outward from the mounting part 72 along the X-axis. The protruding tip position of the mounting protrusion 72d may be approximately flush with the outer surface of the flat piece 73 of the terminal block 7B, or may protrude outward along the X-axis from that, or may be recessed.

[0103] A slit-shaped mounting groove 72e that opens upward along the Z axis and outward along the X axis is formed on the upper surface of the mounting protrusion 72d. As shown in Fig. 15, the mounting groove 72e can fit with the mounting protrusion 70e formed on the inner surface of the first side piece 70d that extends downward along the Z axis from the outer end along the X axis at approximately the center along the Y axis of the terminal cover 70B. By fitting the mounting protrusion 70e into the mounting groove 72e2, it becomes easier to position and attach the terminal cover 70B to the terminal mounting portion 72 of the terminal block 7B.

[0104] Each terminal cover 70B is provided with a second side piece 70f on both sides of the first side piece 70d along the Y axis, each side piece 70f being integral with the terminal cover 70B via a notch. The second side piece 70f covers the connection portion 61 of each terminal 6 from the outside along the X axis. The second side piece 70f also has a function of protecting the connection portion 61 by preventing it from being exposed to the outside. As shown in FIG. 11, the outer surface of the second side piece 70f may be approximately flush with the outer surface of the flat plate piece 73 of the terminal block 70B, or may protrude outward from that surface along the X axis.

[0105] In the coil device 1B according to this embodiment, even when there are a large number of terminals 6, it is possible to reduce the number of terminals 6 attached to each terminal block attachment portion 72, and for example, it becomes easy to align the position of the terminal 6 attached to each terminal block attachment portion with the position of the stepped recess 22a2 formed in the second core 22B. For example, as shown in Fig. 16, in this embodiment, most of the connection portion 61 of each terminal 6 is accommodated inside the stepped recess 22a2 formed in the second core 22B.

[0106] As shown in Fig. 15, most of the connecting wire portion 61 of each terminal is accommodated inside the stepped recess 74 located between the flat plate piece 73 formed on the terminal block 7B and the mounting protrusion 72d, and as a result, it is accommodated inside the stepped recess 22a2 as shown in Fig. 16. In this embodiment, since it has such a configuration, the coil device can be further miniaturized. Also, the heat dissipation property is improved.

[0107] In the above-described embodiment, the terminal mounting portion 72 arranged at one end along the X-axis of the terminal block 7B and the terminal mounting portion 72 arranged at the other end may be provided separately, but by integrally connecting them by the intermediate core cover portion 75a, it becomes easy to simultaneously position and attach the two terminal mounting portions 72, 72 to the upper surface of the core 2B. This also contributes to the miniaturization of the coil device 1B. The other configurations and effects of this embodiment are the same as those of the first or second embodiment described above.

[0108] (Fourth embodiment) 17 to 18, the coil device according to this embodiment differs from the coil devices 1, 1A, and 1B of the above-described embodiments only in the configuration and effects described below, and a description of the common configuration and effects will be omitted. In addition, in Figs. 17 to 18, common reference numerals are used for members common to the members shown in Figs. 1 to 16, and a description of overlapping parts will be omitted.

[0109] The coil device of this embodiment is similar to any one of the first to third embodiments or a combination thereof, except that a core 2C shown in Figure 17 or a core 2D shown in Figure 18 is used instead of the core 2 or 2B according to the previously described embodiments, and a pair of heat sinks 9a, 9a shown in Figure 17 or Figure 18 is used instead of the heat sink 9 according to the previously described embodiments.

[0110] Core 2C shown in Fig. 17 is also a modified example of core 2B shown in Fig. 12, and each of first core 21B and second core 22B shown in Fig. 12 is configured as an assembly of core segments separated at the center along the Y axis. That is, core 2C shown in Fig. 17 has a pair of first core segments 21B1 and a pair of second core segments 22B1.

[0111] Each first core divided body 21B1 has a side leg portion 21c, a center leg divided body 21b2, and a base divided body 21a4, and by butting the butt faces 21b3 formed on each divided body 21B1 against each other, the first core divided bodies 21B1 have a configuration similar to that of the first core 21B shown in Fig. 12. That is, when the first core divided bodies 21B1 shown in Fig. 17 are combined with each other, an elliptical or cylindrical center leg portion 21b is formed as shown in Fig. 12, and a stepped recess 21a2 and an intermediate recess 21a3 are formed.

[0112] Similarly, each second core divided body 22B1 shown in Fig. 17 has a side leg portion 22c, a center leg divided body 22b2, and a base divided body 22a4, and by butting the butt faces 22b3 formed on each divided body 22B1 against each other, it has a configuration similar to that of the second core 22B shown in Fig. 12. That is, when the second core divided bodies 22B1 shown in Fig. 17 are combined with each other, an elliptical or cylindrical center leg portion 22b is formed as shown in Fig. 12, and a stepped recess 22a2 and an intermediate recess 22a3 are formed.

[0113] In this embodiment, instead of the single heat dissipation plate 9 shown in Fig. 12, a combination of a pair of heat dissipation plate segments 9a is used as shown in Fig. 17. Each heat dissipation segment 9a has a top plate portion 90a, a side plate portion 91a extending downward along the Z axis from the outer end along the Y axis of the top plate portion 90a, and an insertion plate portion 92a extending downward along the Z axis from the inner end along the Y axis of the top plate portion 90a.

[0114] The side plate portion 91a shown in FIG. 17 has the same width and length as one side plate portion 91 shown in FIG. 12. The top plate portion 90a shown in FIG. 17 has dimensions such that the top plate portion 90 shown in FIG. 12 is separated at the center along the Y axis. The insertion plate portion 92a is inserted between the butt surfaces 22b3, 22b3 (21b3, 21b3) of the core division bodies 22B1, 22B1 (21B1, 21B1) and has a width approximately half the width of the side plate portion 91a along the X axis. The insertion plate portions 92a formed on each of the pair of heat sinks 9a, 9a are misaligned along the X axis so as not to overlap with each other along the Y axis between the butt surfaces 22b3, 22b3 (21b3, 21b3).

[0115] The core segments 22B1 and 21B1 of this embodiment can be made of the same material as the cores 2 and 2B of the above-described embodiment. Also, the heat sinks 9a and 9a are preferably made of a metal plate or the like having better heat dissipation properties than the core 2C, similar to the heat sink 9 described above.

[0116] In this embodiment, the core 2C is composed of four divided bodies 22B1, 21B1, and the divided bodies 22B1, 21B1 are assembled with the insertion plate parts 92a, 92a of the heat sink 9a inserted between the butt surfaces 22b3, 22b3 (21b3, 21b3) of the divided bodies 22B1, 21B1. Therefore, heat from inside the center leg part, which is most likely to be trapped in heat, is transferred through the insertion plate parts 92a to the top plate part 90a and the side plate part 91a, and can be effectively dissipated from there to the outside.

[0117] In this embodiment, the cores 21B and 22B in the embodiment shown in FIG. 12 are each divided into two, but the cores 21, 22 shown in FIG. 2B or FIG. 9 may each be divided into two.

[0118] Furthermore, the core 2D shown in Fig. 18 is also a further modified example of the core 2B shown in Fig. 12, and is configured as an assembly of core segments obtained by separating and dividing the core 2D at different division positions and with different division numbers from the first core 21B and the second core 22B shown in Fig. 12. That is, the core 2D shown in Fig. 18 has a pair of first core segments 21B2, a pair of second core segments 22B2, and a pair of divided side plate portions 23.

[0119] Each first core divided body 21B2 has a center leg divided body 21b2 and a base divided body 21a4, and by butting the butt faces 21b3 formed on each divided body 21B2 together, the first core divided bodies 21B2 have a configuration similar to that of the first core 21B not having the side leg portion 21c shown in Fig. 12. That is, when the first core divided bodies 21B2 shown in Fig. 18 are combined with each other, an elliptical or cylindrical center leg portion 21b is formed as shown in Fig. 12, and a stepped recess 21a2 and an intermediate recess 21a3 are formed.

[0120] Similarly, each second core divided body 22B2 shown in Fig. 18 has a center leg divided body 22b2 and a base divided body 22a4, and by butting the butt faces 22b3 formed on each divided body 22B2 against each other, the second core divided bodies 22B2 have a configuration similar to that of the second core 22B shown in Fig. 12. That is, when the second core divided bodies 22B2 shown in Fig. 18 are combined with each other, an elliptical or cylindrical center leg portion 22b is formed as shown in Fig. 12, and a stepped recess 22a2 and an intermediate recess 22a3 are formed.

[0121] The divided side plate portion 23 shown in Fig. 18 has a configuration in which the side plate portions 21c, 22c located at one end along the Y axis of the cores 21B, 22B shown in Fig. 12 are connected along the Z axis and separated from the base portions 21a, 22a. The end portion along the Z axis of the divided side plate portion 23 shown in Fig. 18 is fixed, for example, by an adhesive, to the inner surface near the outer end along the Y axis of each of the base divided bodies 21a4, 22a4.

[0122] Also in this embodiment, instead of the single heat dissipation plate 9 shown in Fig. 12, a combination of a pair of heat dissipation plate segments 9a is used as shown in Fig. 18. Each heat dissipation segment 9a has a similar configuration to the heat dissipation segment 9a shown in Fig. 17, and therefore a detailed description thereof will be omitted.

[0123] In this embodiment, the core 2D is composed of six divided bodies 22B2, 21B2, 23, and the divided bodies 22B2, 21B2, 23 are assembled with the insertion plate parts 92a, 92a of the heat sink 9a inserted between the butt surfaces 22b3, 22b3 (21b3, 21b3) of the divided bodies 22B2, 21B2. Therefore, heat from inside the center leg part, which is most likely to be trapped in heat, is transferred through the insertion plate parts 92a to the top plate part 90a and the side plate part 91a, and can be effectively dissipated from there to the outside.

[0124] In this embodiment, the core 2B of the embodiment shown in Fig. 12 is divided into six parts, but the core 2 shown in Fig. 2B or Fig. 9 may be divided into six parts. The other configurations and effects of this embodiment are the same as those of the first, second or third embodiment described above.

[0125] The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present invention.

[0126] For example, in the above-described embodiment, the first opposing end 42 of the first wire winding portion 40 or the second opposing end 52 of the second wire winding portion 50 may be joined to the surface of the spacer 10 using a joining method other than thermocompression bonding, such as using an adhesive.

[0127] In the above embodiment, the first wire 4 constituting the first wire winding section 40 and the second wire 5 constituting the second wire winding section 50 are each composed of separate wires, but the first wire 4 and the second wire 5 may be composed of a single continuous wire. In that case, the first wire winding section 40 and the second wire winding section 50 form a continuous single coil without constituting a transformer in the circuit, and can be used as a part of a transformer or as a coil device other than a transformer. Examples of coil devices other than a transformer include inductors, resonant coils, choke coils, PFC coils, and reactor coils.

[0128] Although the spacer 10 is ring-shaped, it may be partially cut out or may be divided in the circumferential direction. The spacer 10 is preferably configured as a single layer along the Z-axis (winding axis) direction, but may be configured as a laminate of multiple spacers.

[0129] Furthermore, the spacer 10 may have any shape or configuration as long as it has at least one of the outer recess 11 that allows a fluid to flow from the outside to the inside in the radial direction of the first opposed end 42 or the second opposed end 52, the inner recess 12 that allows a fluid to flow from the inside to the outside in the radial direction of the first opposed end 42 or the second opposed end 52, and a through hole that allows a fluid to flow from the first opposed end 42 to the second opposed end 52. For example, the spacer 10 may be a mesh itself, or one or both sides of the spacer 10 may have radial or mesh-like grooves formed thereon that connect the outside and inside of the spacer 10 in the radial direction.

[0130] Furthermore, in the above-described embodiment, the flow path forming region of the spacer 10 is configured by a notch or a through hole penetrating the front and back surfaces of the spacer, but the flow path forming region may be a groove formed on only one surface of the spacer 10, or may be a groove formed on both surfaces of the spacer.

[0131] Furthermore, in the above-described embodiment, the spacer 10 is disposed inside the coil body 30, but in a coil device according to another embodiment, the spacer 10 does not necessarily have to be provided.

[0132] Furthermore, in the coil devices 1, 1A, and 1B of the above-described embodiments, the coil core assembly 3 is housed inside the case 8 filled with heat dissipating resin to improve heat dissipation, but in some cases, the case 8 and the heat dissipating resin 82 may not necessarily be required. For example, a cooling fluid such as cooling air may be directly applied to the coil core assembly 3 shown in FIG. 2A.

[0133] Moreover, a coil device may be assembled by combining any of the above-described embodiments. [Explanation of symbols]

[0134] 1, 1A, 1B... Coil device 2,2B,2C,2D...Core 21, 21B…First core 21B1, 21B2...First core division body 21a…Base section 21a2...Step-shaped recess 21a3...Middle recess 21a4...Base division body 21b…middle leg 21b1...tip 21b2…Middle leg split body 21b3…butt surface 21c...Side leg 21c1...Tip 22,22B…Second core 22B1, 22B2...Second core division 22a…Base section 22a1...recess 22a2...Step-shaped recess 22a3…Middle recess 22a4...Base division body 22b…middle leg 22b1...tip 22b2…Middle leg split body 22b3…butt surface 22c...Side leg 22c1...Tip 22c2…Side end surface 23…Split side leg 3...Coil core assembly 30…Coil body 4…First wire 40…First wire winding portion 41a, 41b...Lead section 42…First opposing end 45…Spiral recess 5…Second wire 50...Second wire winding section 51a, 51b...Lead section 52...Second opposing end 55…Spiral recess 6…Terminal 60...Terminal base 61...Connection section 62…External connection part 7,7A,7B…Terminal block 70,70B…Terminal cover 70a...Gripping piece 70b…Claw part 70c...Through hole 70d…First side piece 70e…Mounting protrusion 70f…Second side piece 71…Mounting groove 72...Terminal mounting section 72a…Inner surface 72b…Inner recess 72c…External surface 72d…Mounting protrusion 72e…Mounting groove 73...Flat piece 73a…Inner surface 73b…Attachment piece 74...Bending piece 74a…Inner surface 74b...Elastic piece 75…Core cover part 75a…Intermediate core cover part 76…Through groove 77…Partition 77a...Rise piece 77a1…Central recess 77a2…Inner convex part 77b...Fitting protrusion 77c...Through hole 8. Case 80...Bottom plate 81…Side panel 82…Heat dissipating resin 9…Heat sink 9a…Radiation plate division body 90,90a…Top plate 91,91a...Side plate part 92a…Insertion plate section 10…Spacer 11…Outer recess 12…Inner recess 13...Outer periphery 14...Inner circumference 16...Through hole

Claims

1. A core including a magnetic material; a wire wound around at least a portion of the core; A terminal block for holding a terminal to which a lead portion of the wire is connected, At least a portion of the terminal block is fixed to a portion of the core.

2. The coil device according to claim 1 , wherein the terminal block is disposed at a position covering at least a portion of an upper surface of the core.

3. The wires include at least a first wire and a second wire; The lead portion has a plurality of lead portions, The terminal has a plurality of terminals, 2. The coil device according to claim 1, wherein the terminal block is provided with terminals to which the lead portions of the first wires are connected and terminals to which the lead portions of the second wires are connected.

4. 4. The coil device according to claim 3, wherein the terminal block is provided at one end of the core along a first axis that is substantially perpendicular to the winding axis of the wire.

5. The coil device according to claim 3 , wherein the terminal block has a terminal mounting portion having mounting grooves into which four or more of the terminals are respectively fitted.

6. The terminal block includes:

6. The coil device according to claim 5, further comprising a core cover portion that is continuous with the terminal mounting portion and covers a portion of the upper surface of the core other than a portion of the upper surface covered by the terminal mounting portion.

7. The coil device according to claim 6 , wherein the core cover portion has a through groove through which a heat sink disposed in contact with an upper surface of the core passes.

8. The terminal block includes: a first terminal attachment portion having attachment grooves into which terminals to be connected to the pair of lead portions of the first wire are fitted, a second terminal attachment portion having attachment grooves into which terminals to be connected to the pair of lead portions of the second wire are fitted, 4. The coil device according to claim 3, wherein the first terminal attachment portion and the second terminal attachment portion are disposed on both ends of the core along a first axis that is substantially perpendicular to a winding axis of the wire.

9. the first terminal mounting portion and the second terminal mounting portion are integrally connected by an intermediate core cover portion, The coil device according to claim 8 , wherein the intermediate core cover portion covers a central portion of an upper surface of the core located between the first terminal attachment portion and the second terminal attachment portion.

10. The coil device according to claim 9 , wherein the intermediate core cover portion has a through groove through which a heat sink disposed in contact with an upper surface of the core passes.

11. The coil device according to claim 9 , wherein the intermediate core cover portion has at least one of a through hole penetrating from an inner surface to an outer surface of the intermediate core cover portion and a concave-convex portion formed on the outer surface.

12. 12. The coil device according to claim 1, wherein the terminal block has a bent piece that fits into a recess formed in a side of the core.

13. 13. The coil device according to claim 12, wherein the bent piece is integrated with the terminal block so that a connection portion of the terminal fits inside the recess of the core.

14. 12. The coil device according to claim 1, wherein a partition plate is interposed between one end of the wound portion of the wire in the winding axis direction and the core.

15. 12. The coil device according to claim 1, wherein the core has a center leg disposed through the windings of the wire.

16. The coil device of claim 15 , wherein the core further includes a side leg that covers at least a portion of an outer periphery of the first wire winding portion or an outer periphery of the second wire winding portion.

17. The winding portion of the wire is wound around a case.

12. The coil device according to claim 1, wherein the inside of the case is filled with a heat dissipating resin up to a position where at least a part of the wound portion of the wire is immersed.

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