Coil device

Abstract

To provide a coil device to which a terminal can be easily while allowing size reduction.SOLUTION: A coil device has: a core 2 containing a magnetic material; wires 4, 5 wound around at least a part of the core 2; and a terminal block 7 holding a terminal 6 to which lead parts 41a, 41b, 51a, 51b of the wires 4, 5 are connected. The terminal block 7 has attachment grooves 71 that allow the terminal 6 to which the lead parts 41a, 41b, 51a, 51b of the wires 4, 5 are connected to be inserted from a direction along an X-axis generally perpendicular to a winding axis of the wires 4, 5.SELECTED DRAWING: Figure 2C

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 formed on the bobbin. The bobbin is provided with a terminal block with a terminal attached thereto.

[0003] As shown in Patent Document 1, in conventional coil devices, terminals to which the lead portions of the wires are connected are generally attached and fixed to the surface of a terminal block from above along the winding axis of the wire. Recently, there has been an increasing demand for miniaturization of coil devices, and a configuration in which the terminal block is as close to the core as possible is required. In addition, as the current of coil devices increases, the wire diameter has become thicker, making it difficult to move the terminals to which the lead portions of the wires are connected close to the terminal block and attach the terminals from above the terminal block, due to the resistance to the repulsive force caused by the elastic deformation of the wire. [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 which can be miniaturized and to which terminals can be easily attached. [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 coiled 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, The terminal block has a mounting groove into which the terminal, to which the lead portion of the wire is connected, can be inserted from a direction along a first axis that is substantially perpendicular to the winding axis of the wire.

[0007] In this coil device, even if the terminal block is brought as close as possible to the core to reduce the size of the coil device, the terminal block has a mounting groove into which the terminal to which the lead portion of the wire is connected can be inserted from a direction along the first axis that is approximately perpendicular to the winding axis of the wire, making it easy to attach the terminal to the terminal block. For example, even if the wire has a large diameter and the repulsive force due to the elastic deformation of the wire is strong, the terminal can be easily temporarily fixed to the terminal block by simply inserting the terminal to which the lead portion of the wire is connected into the terminal block from a direction along the first axis that is approximately perpendicular to the winding axis of the wire. After that, the terminal can be easily fixed to the terminal block using an adhesive or the like.

[0008] Preferably, the terminal has a connection portion to which the lead portion of the wire is connected, an external connection portion for connection to an external circuit, and a terminal base portion having an insertion protrusion to be inserted into the insertion groove of the mounting groove. Preferably, the terminal base portion is located between the connection portion and the external connection portion.

[0009] Preferably, the coil device further includes a terminal cover attached to the terminal block so as to cover at least the terminal base portion attached to the attachment groove and to expose the external connection portion. By attaching the terminal cover to the terminal block so as to cover the terminal base with the terminal cover, it is possible to prevent the terminal from coming out of the attachment groove of the terminal block.

[0010] A coil device according to another aspect of the present invention includes: A core including a magnetic material; a wire coiled 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, the terminal has a connection portion to which the lead portion of the wire is connected, an external connection portion for connection to an external circuit, and a terminal base portion to be attached to the mounting groove of the terminal block; A terminal cover is attached to the terminal block so as to cover at least the terminal base portion and to expose the external connection portion.

[0011] Even in this coil device, even if the terminal block is brought as close as possible to the core to reduce the size of the coil device, the terminal cover is attached to the terminal block so as to cover at least the terminal base portion and expose the external connection portion, making it easy to attach the terminal to the terminal block. For example, even if the wire diameter is large and the repulsive force due to the elastic deformation of the wire is strong, the terminal to which the lead portion of the wire is connected can be easily fixed to the terminal block by attaching the terminal cover so as to cover the terminal base portion of the terminal.

[0012] Preferably, the terminal cover has a side piece that covers the connection portion of the terminal. By covering the connection portion with the side piece, the connection portion is protected, and the risk of impact being applied to the connection portion during transportation of the coil device, etc. is reduced, thereby improving the reliability of the connection portion.

[0013] Preferably, the terminal cover has an injection hole for injecting adhesive toward the terminal base portion. By injecting adhesive from the injection hole toward the terminal base portion of the terminal, the terminal cover is reliably fixed to the terminal and the terminal cover is reliably fixed to the terminal block.

[0014] Preferably, the terminal base has a through hole corresponding to the position of the injection hole. The adhesive injected through the injection hole passes through the through hole of the terminal base and reaches the mounting groove of the terminal block, so that the terminal is fixed to the terminal block more reliably and the terminal cover is also fixed to the terminal and the terminal block more reliably.

[0015] Preferably, a recess is formed in the bottom surface of the mounting groove at a position corresponding to the through hole. The adhesive injected through the injection hole passes through the through hole of the terminal base, reaches and accumulates in the recess of the mounting groove of the terminal block, thereby more reliably fixing the terminal to the terminal block and more reliably fixing the terminal cover to the terminal and the terminal block.

[0016] Preferably, the area of ​​the recess is larger than the area of ​​the through hole of the terminal. With this configuration, a larger amount of adhesive is accumulated in the recess, and the terminal is more securely fixed to the terminal base, and the terminal cover is also more securely fixed to the terminal and the terminal block.

[0017] In addition, even if the terminal cover does not have an injection hole or the terminal base portion of the terminal does not have a through hole, a recess may be formed in the bottom surface of the mounting groove at a position corresponding to the through hole of the terminal.

[0018] Preferably, the terminal block is disposed in a position that covers at least a portion of the upper surface of the core. When the terminal block is fixed to the core, there is no need to use a bobbin. In addition, when there is no need to use a bobbin, it is possible to reduce the distance between the winding portion of the wire and the core, making it possible to reduce the size and weight of the coil device. Bringing the terminal block closer to the core also contributes to the miniaturization of the coil device.

[0019] Furthermore, it becomes possible to directly cool the windings and core of the wire using heat dissipating resin without using a bobbin, improving heat dissipation and enabling the coil device to handle larger currents. Even in a coil device that uses a case filled with heat dissipating resin, the case can be made smaller and heat dissipation is particularly improved. Although a bobbin may be used, it is preferable to place the terminal block as close to the core as possible to reduce the size of the coil device.

[0020] 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.

[0021] 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.

[0022] 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.

[0023] 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.

[0024] 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.

[0025] 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.

[0026] 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.

[0027] 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.

[0028] 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.

[0029] 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.

[0030] 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.

[0031] The intermediate core cover portion has a through hole penetrating from an inner surface to an outer surface of the intermediate core cover portion. The intermediate core cover may have at least one of a through hole and a concave-convex portion formed on the outer surface. By forming a through hole and / or a concave-convex portion in the intermediate core cover, it contributes to preventing warping of the terminal block including the core cover, and also contributes to reducing the weight of the coil device and improving the cooling efficiency.

[0032] 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.

[0033] 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.

[0034] 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.

[0035] 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.

[0036] 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]

[0037] [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. [Diagram 3] FIG. 3 is a perspective view of the terminal block body shown in FIG. 2C, seen from a different angle. [Figure 4] FIG. 4 is a schematic perspective view of a coil device according to another embodiment of the present invention. [Diagram 5] FIG. 5 is a schematic perspective view of the coil device shown in FIG. 4 with the terminal cover removed. [Figure 6] FIG. 6 is a schematic exploded perspective view of the coil device shown in FIG. [Figure 7] FIG. 7 is a schematic exploded perspective view showing the relationship between the terminal block and the partition plate shown in FIG. [Figure 8] FIG. 8 is a schematic perspective view of a coil device according to still another embodiment of the present invention. [Figure 9] FIG. 9 is a schematic exploded perspective view of the coil device shown in FIG. [Figure 10] FIG. 10 is a perspective view of the coil device shown in FIG. 8 with the core and the heat dissipation cover removed. [Figure 11] FIG. 11 is an exploded perspective view of the coil device shown in FIG. 10 with a terminal cover removed. [Figure 12] FIG. 12 is an exploded perspective view of the coil device shown in FIG. 11, seen from a different angle. [Figure 13] FIG. 13 is a perspective view of the coil device shown in FIG. 8 with the terminal block removed and the terminal cover omitted. [Figure 14] 14 is a cross-sectional view of a main part showing the relationship between a terminal cover, a terminal, and a terminal block of the coil device taken along line XIV-XIV shown in FIG. [Figure 15] FIG. 15 is a schematic perspective view of a coil device according to still another embodiment of the present invention. [Figure 16] FIG. 16 is a schematic exploded perspective view in which a terminal block and a terminal cover are disassembled from the coil device shown in FIG. [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

[0038] 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.

[0039] (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.

[0040] 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. 2A. 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.

[0041] 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.

[0042] 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.

[0043] These cores 21 and 22 are not particularly limited as long as they are magnetic cores, and may be made of, for example, ferrite, metal magnetic material, or resin containing magnetic powder. In this embodiment, 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.

[0044] 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.

[0045] 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.

[0046] 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.

[0047] 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.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] The terminal 6 having the connecting wire portion 61, the terminal base portion 60 and the external connection portion 62 can be formed, for example, by pressing a single metal plate. The connecting wire portion 61 is bent downward at approximately 90 degrees along the Z axis relative to the base portion 60, and the external connection portion 62 is bent upward at approximately 90 degrees along the Z axis relative to the base portion 60. The terminal base portion 60 has insertion convex pieces 60a formed on both sides (or one side) of the terminal base portion 60 along the Y axis in a plane flush with the base portion 60.

[0052] The terminal base portion 60 of each terminal 6 is attached from the outside along the X-axis into a plurality of attachment grooves 71 provided at predetermined intervals along the Y-axis direction on the terminal block 7, and the insertion protrusion 60a of the terminal 6 is inserted along the X-axis into the insertion groove 71a formed in the attachment groove 71. The attachment groove 71 is formed on the upper surface of the terminal block 7 along the Z-axis, and at the outer end along the X-axis, an opening end of the insertion groove 71a is formed, from which the insertion protrusion 60a of the terminal 6 is inserted.

[0053] A stopper wall 71b is formed at the inner end along the X-axis of each mounting groove 71. The base portion 60 of the terminal 6, which is inserted from outside the X-axis along the bottom surface of the mounting groove 71b, abuts against the stopper wall 71b at the intersection with the external connection portion 62, and the base portion 60 is positioned along the X-axis with respect to the mounting groove 71b. In addition, the base portion 60 of the terminal 6 is also positioned along the Y-axis and Z-axis with respect to the mounting groove 71b because the insertion convex piece 60a engages with the insertion groove 71a.

[0054] A recess 71c is formed on the bottom surface of each mounting groove 71 at a position corresponding to the through hole 60b of the base portion 60 when the base portion 60 of the terminal 6 is positioned in the mounting groove 71. The recess 71c has an area larger than the opening area of ​​the through hole 60b so that the through hole 60b of the terminal 6 is accommodated when viewed from above along the Z axis, and is recessed further downward along the Z axis from the bottom surface of the insertion groove 71. In this embodiment, the recess 71c is capable of storing adhesive injected from the through hole 60b. Note that, in this embodiment, the recess 71c opens outward at the outer end along the X axis, but it may not necessarily be an opening recess.

[0055] 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.

[0056] 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.

[0057] 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.

[0058] 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.

[0059] 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.

[0060] 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.

[0061] 2B, a spacer 10 is disposed between the first wire winding portion 40 and the second wire winding portion 50. The spacer 10 has a predetermined thickness along the winding axis (Z-axis) of the first wire winding portion 40 and the second wire winding portion. The predetermined thickness is not particularly limited, but is, for example, 0.2 to 2.0 mm.

[0062] In this embodiment, the spacer 10 is preferably fixed to the upper end of the first wire winding portion 40 and / or the lower end of the second wire winding portion 50 by means of thermocompression or adhesive. Preferably, these are thermocompression-bonded in the axial direction by a thermocompression layer that covers the outer periphery of the wires 4 and 5 that constitute the wire winding portions 40 and 50.

[0063] In this embodiment, the spacer 10 has a plurality of outer recesses along the circumferential direction that are recessed from the outer circumferential position of the spacer 10 toward the inner circumferential position and do not contact the upper end portion along the Z axis of the first winding portion 40 and the lower end portion along the Z axis of the second winding portion 50. The spacer 10 also has a plurality of inner recesses along the circumferential direction that are recessed from the inner circumferential position of the spacer 10 toward the outer circumferential position and do not contact the upper end portion along the Z axis of the first winding portion 40 and the lower end portion along the Z axis of the second winding portion 50.

[0064] In this embodiment, both the outer and inner circumferences of the ring-shaped spacer 10 have a repeated uneven shape, with outer and inner recesses alternately provided along the circumferential direction. The number of repetitions of the outer recesses or inner recesses along the circumferential direction is not particularly limited, but is preferably about 3 to 20, and more preferably about 5 to 15.

[0065] The outer recess and the inner recess 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.

[0066] Therefore, the outer recess functions as an outer flow path that allows fluid to flow from the outside to the inside in the radial direction of the upper end of the first wire winding portion 40 or the lower end of the second wire winding portion 50 (including the reverse flow), and also functions as an axial flow path that allows fluid to flow along the Z axis. The inner recess functions as an inner flow path that allows fluid to flow from the inside to the outside in the radial direction of the windings 40, 50 (including the reverse flow), and also functions as an axial flow path that allows fluid to flow along the Z axis.

[0067] In this embodiment, the circumferential width of the outer recess is preferably wider at the outer circumferential position than at the inner circumferential position, and the circumferential width of the inner recess is preferably wider at the inner circumferential position than at the outer circumferential position. Also, under the same radial position, it is preferable that the circumferential width of the outer recess is wider than the circumferential width of the inner recess, but they may be the same or vice versa.

[0068] 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 and the outer recesses are continuous along the circumferential direction, but one or more of the inner recesses or the outer recesses may have a cut part that penetrates the outer circumference and the inner circumference.

[0069] The outer periphery of spacer 10, which has the greatest outer diameter along the radial direction, 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 the outer periphery of spacer 10 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.

[0070] Furthermore, the inner periphery, which has the smallest inner diameter along the radial direction of the spacer 10, is designed to be close to the outer periphery of the middle leg 21b or 22b of the core 2, and preferably protrudes inward from the inner periphery of the wire winding portion 40 or 50, but does not have to protrude and may be flush. The inner periphery may be in contact with the outer periphery of the middle leg 21b or 22b of the core 2. If it is in contact, heat from the middle leg 21b or 22b of the core 2 is more easily transferred to the spacer, improving heat dissipation.

[0071] 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. 1 is interposed through the gap, improving the heat dissipation between the outer peripheral surfaces of the center leg portions 21b and 22b and the inner peripheral surfaces of the winding portions 40 and 50.

[0072] In the coil device 1 according to this embodiment, the spacer 10 having a predetermined thickness is disposed between the first wire winding part 40 and the second wire winding part 50, so that the distance between the upper end of the first wire winding part 40 and the lower end of the second wire winding part 50 can be controlled by the thickness of the spacer 10. As a result, the leakage of the coil device 1 can be adjusted.

[0073] In addition, in the coil device 1 according to this embodiment, the spacer 10 having a predetermined thickness has an outer recess corresponding to the outer flow passage and the axial flow passage, and an inner flow passage corresponding to the inner flow passage and the axial flow passage.

[0074] Through the outer recess, heat dissipating resin 82, which is a cooling fluid, can be drawn between the first wire winding portion 40 and the second wire winding portion 50 from the outside to the inside in the radial direction of the winding portions 40 and 50. Also, the inner recess of the spacer 10 can draw heat dissipating resin 82 between the first wire winding portion 40 and the second wire winding portion 50 from the inside to the inside or from the outside to the inside in the radial direction of the winding portions 40 and 50.

[0075] Furthermore, in this embodiment, a continuous helical recess is formed in the upper end of the winding portion 40 and the lower end of the winding portion 50 in accordance with the helical shape of the wire 4 or 5 constituting the winding portion 40 or 50, respectively. The heat dissipating resin 82 drawn into the inside of the winding portion 40 or 50 through the outer recess can also flow into the inner recess located adjacent in the circumferential direction through the helical recess. Alternatively, conversely, the heat dissipating resin 82 can flow from the inner recess located adjacent in the circumferential direction to the outer recess through the helical recess.

[0076] Furthermore, the outer recess and the inner recess of the spacer 10 are also axial through grooves that do not contact either the first wire winding portion 40 or the second wire winding portion, so they also allow the heat dissipation resin to flow along the Z-axis direction. In this way, the heat dissipation resin 82 shown in Fig. 1 can be introduced between the winding portions 40, 50, and heat is transferred from the inner periphery side of the winding portions 40 and 50, where heat is most likely to be trapped, to the case 8 via the spacer 10 and the heat dissipation resin 82 located in the recess, improving the heat dissipation of the coil device 1.

[0077] In this embodiment, the outer recess and the inner recess 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 upper end of the winding portion 40 and the lower end 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.

[0078] By providing flow path forming regions on the surface of the spacer 10 at multiple 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 wire winding portions 40, 50 at multiple 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 multiple locations along the circumferential direction, the spacer 10 has a predetermined thickness, so that the leakage adjustment of the coil device 1 is well maintained.

[0079] In addition, in this embodiment, the circumferential width of the outer recess 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 winding portions 40, 50 from the outside to the inside in the radial direction of the winding portion 40 or 50.

[0080] Furthermore, the width of the inner recess of spacer 10 along the circumferential direction is wider at the inner circumferential position than at the outer circumferential position, which makes it easy to draw heat dissipating resin 82 between winding portions 40, 50 from the inside to the outside in the radial direction of winding portion 40 or 50. Alternatively, heat dissipating resin 82 can be drawn between winding portions 40, 50 along the outer recess from the outside to the inside in the radial direction of winding portion 40 or 50, and heat dissipation resin 82 can be stored at the inner circumferential position where the width of the inner recess is wider, thereby improving heat dissipation from the inside of winding portion 40 or 50 and the outer circumferential surface of middle leg portion 21b or 22b of core 2.

[0081] In this embodiment, the inner recess and the outer recess are arranged adjacent to each other along the circumferential direction, so that the heat dissipation resin can be drawn between the winding parts 40, 50 in both the radial direction from the inside to the outside and from the outside to the inside of the winding part 40 or 50, further improving the heat dissipation. Also, the heat dissipation resin 82 can flow between the adjacent inner recess and outer recess through, for example, a spiral recess formed at the upper end of the winding part 40 or the lower end of the winding part 50.

[0082] Furthermore, in this embodiment, the width of the outer recess along the circumferential direction is made wider than the width of the inner recess along the circumferential direction. Since the middle legs 21b and 22b of the core 2 are arranged closely to the inner circumferential portion that is the central opening of the spacer 10, it is easier to create a flow of the heat dissipation resin 82 from the outside to the inside in the radial direction of the spacer 10 than a flow of the heat dissipation resin 82 from the inside to the outside in the radial direction of the spacer 10. Therefore, by making the width of the outer recess along the circumferential direction wider than the width of the inner recess along the circumferential direction, it becomes easier to draw the heat dissipation resin 82 between the winding portions 40, 50.

[0083] 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.

[0084] 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.

[0085] 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.

[0086] 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.

[0087] 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.

[0088] 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.

[0089] 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.

[0090] 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.

[0091] 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.

[0092] 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.

[0093] Furthermore, in this embodiment, even if the coil device 1 is miniaturized by bringing the terminal block 7 closer to the core 2, the work of attaching the terminals 6 to which the lead portions 41a, 41b, 51a, and 51b of the wires 4 and 5 are respectively connected to the terminal block 7 is facilitated. This is because the terminal block 7 has attachment grooves 71 that allow the terminals 6 to be inserted from a direction along the X-axis that is approximately perpendicular to the winding axes of the wires 4 and 5.

[0094] For example, even if the wires 4, 5 have a large diameter and the repulsive force due to elastic deformation of the wires 4, 5 is strong, the terminal 6 to which the lead portions 41a, 41b, 51a, 51b of the wires 4, 5 are connected can be simply inserted toward the terminal block 7 from the direction along the X-axis, whereby the insertion convex piece 60a of the base portion 60 engages with the insertion groove 71a, and the terminal 6 can be easily temporarily fixed to the terminal block 7. Thereafter, the terminal 6 can be easily fixed to the terminal block 7 by, for example, pouring adhesive from the through hole 60b into the recess 71c formed in the bottom surface of the mounting groove 71b.

[0095] In addition, in this embodiment, the terminal cover 70 is attached to the terminal block 7 so as to cover at least the terminal base portion 60 mounted in the mounting groove 71 and expose the external connection portion 62, thereby effectively preventing the terminal 6 from falling out of the mounting groove 71 of the terminal block 7.

[0096] Second embodiment As shown in Figures 4 to 7, 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 4 to 7, common members to those shown in Figures 1 to 3 are given the same reference numerals, and a description of overlapping parts will be omitted.

[0097] As shown in Fig. 4, the terminal block 7A of this embodiment has a core cover portion 75. As shown in Fig. 5, the core cover portion 75 is provided continuous with the terminal mounting portion 72, and is adapted to cover 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.

[0098] 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.

[0099] 7, 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.

[0100] 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. 6. The flat plate piece 73 of the terminal block 7A shown in Fig. 7 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. 6.

[0101] 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.

[0102] 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.

[0103] 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. 6 is disposed in this gap. A gap extending along the Y-axis is also 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. 5 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.

[0104] 6, 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.

[0105] In this embodiment, the terminal mounting portion 72 of the terminal block 7A shown in Fig. 5 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. For example, 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.

[0106] 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.

[0107] Furthermore, the terminal block 7A of the coil device 1A of this embodiment also has a mounting groove 71 having an insertion groove 71a, and the terminal 6 can be attached by being inserted into the mounting groove 71 along the X-axis, similarly to the above-described embodiment.

[0108] 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.

[0109] Third embodiment As shown in Figures 8 and 9, 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 8 and 9, common reference numerals are used to designate members common to those shown in Figures 1 to 7, and a description of overlapping parts will be omitted.

[0110] As shown in Fig. 8, the terminal block 7B of this embodiment has a middle core cover portion 75a. As shown in Fig. 9, the middle core cover portion 75a 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.

[0111] 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.

[0112] 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.

[0113] 9, 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-split core with an E-shaped longitudinal 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.

[0114] 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.

[0115] 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.

[0116] 9, 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.

[0117] 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. 11, the connection portion 61 of the terminal 6 is disposed outside the stepped bent pieces 74.

[0118] As shown in Fig. 13, 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.

[0119] 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.

[0120] 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. 12, 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. The mounting protrusion 70e fits into the mounting groove 72e2, making it easier to position and attach the terminal cover 70B to the terminal mounting portion 72 of the terminal block 7B.

[0121] 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 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. 8, 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.

[0122] 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. 13, 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.

[0123] As shown in Fig. 12, 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. 13. In this embodiment, since it has such a configuration, the coil device can be further miniaturized. Also, the heat dissipation property is improved.

[0124] In the above 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.

[0125] The terminal block 7B of the coil device 1B of this embodiment also has a mounting groove 71 having an insertion groove 71a, and similarly to the previously described embodiment, the terminal 6 can be attached by inserting it into the mounting groove 71 along the X-axis. However, unlike the previously described embodiment, in this embodiment, as shown in Fig. 11, the terminal cover 70B has side pieces 70f, 70f that cover the connection parts 61 of the terminals 7, and by the side pieces 70f, 70f covering the connection parts 61, 61, the connection parts 61, 61 are protected, and the risk of impact being applied to the connection parts 61, 61 during transportation of the coil device 1B, etc. is reduced, improving the reliability of the connection parts 61, 61.

[0126] 11, terminal cover 70 has injection hole 70g for injecting adhesive toward terminal base portion 60 of terminal 6. Injecting adhesive from injection hole 70g toward terminal base portion 60 of terminal 6 ensures that terminal cover 70B is fixed to terminal 6 and also ensures that terminal cover 70B is fixed to terminal block 7B.

[0127] Furthermore, in this embodiment, a through hole 60b is formed in the terminal base portion 60 corresponding to the position of the injection hole 70g, so that the adhesive injected through the injection hole 70g shown in Figure 14 passes through the through hole 60b in the terminal base portion 60 and reaches the mounting groove 71 of the terminal block 7B, making the fixation of the terminal 6 to the terminal block 7B more secure and also making the fixation of the terminal cover 70B to the terminal 6 and terminal block 7B more secure.

[0128] Furthermore, a recess 71c is formed in the bottom surface of the mounting groove 71 at a position corresponding to the through hole 60b. The adhesive injected through the injection hole 70g passes through the through hole 60b of the terminal base portion 60, reaches and accumulates in the recess 71c of the mounting groove 71 of the terminal block 7B, thereby more reliably fixing the terminal 6 to the terminal block 70B and more reliably fixing the terminal cover 70B to the terminal 6 and terminal block 7B.

[0129] In this embodiment, the area of ​​the recess 71c (as viewed from above along the Z axis) is larger than the area of ​​the through hole 60b of the terminal 6, so that the amount of adhesive that accumulates in the recess 71c is greater, and the terminal 6 is more securely fixed to the terminal block 7B, and the terminal cover 70B is more securely fixed to the terminal 6 and the terminal block 7B. In this embodiment, the injection hole 70g of the terminal cover 70B has a countersunk hole 70h formed thereon. The countersunk hole 70h has a larger opening area than the injection hole g, and the adhesive can also accumulate in that portion, making the fixation by the adhesive more secure. The other configurations and effects of this embodiment are the same as those of the first or second embodiment described above.

[0130] (Fourth embodiment) As shown in Fig. 15 and Fig. 16, the coil device 1C according to this embodiment differs from the coil device 1B according to the embodiment described above only in the configuration and operational effects described below, and a description of the common configuration and operational effects will be omitted. Note that in Fig. 15 and Fig. 16, some of the components common to the components shown in Figs. 1 to 14 are given the same reference numerals, but not all of the common components are given the same reference numerals. Below, only the parts that are particularly different from the embodiment described above will be described, and a description of the overlapping parts will be omitted.

[0131] As shown in Fig. 15 and Fig. 16, the terminal block 7C of this embodiment is similar to the terminal block 7B, except that it does not have the intermediate core cover 75a, as compared with the terminal block 7B having the intermediate core cover portion 75a shown in Fig. 10 and Fig. 11. That is, the terminal block 7C of this embodiment is composed of a pair of terminal blocks 7C separated along the X-axis, and each terminal block 7C has a terminal mounting portion 72 having an insertion groove 71a, a stopper wall 71b, and a mounting groove 71 having a recess 71c shown in Fig. 8 to Fig. 14. In this embodiment, the pair of terminal blocks 7C are directly attached to the upper surface of the core. The other configurations and effects of this embodiment are the same as those of the first to third embodiments described above.

[0132] Fifth embodiment As shown in Fig. 17 and Fig. 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 Fig. 17 and Fig. 18, common reference numerals are used for members common to the members shown in Fig. 1 to Fig. 13, and a description of overlapping parts will be omitted.

[0133] 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.

[0134] Core 2C shown in Fig. 17 is, for example, a modified example of core 2B shown in Fig. 9, and each of first core 21B and second core 22B shown in Fig. 9 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.

[0135] 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. 9. 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. 9, and a stepped recess 21a2 and an intermediate recess 21a3 are formed.

[0136] 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. 9. 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. 9, and a stepped recess 22a2 and an intermediate recess 22a3 are formed.

[0137] In this embodiment, instead of the single heat dissipation plate 9 shown in Fig. 9, 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.

[0138] The side plate portion 91a shown in FIG. 17 has the same width and length as one side plate portion 91 shown in FIG. 9. The top plate portion 90a shown in FIG. 17 has dimensions such that the top plate portion 90 shown in FIG. 9 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).

[0139] 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.

[0140] 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, the heat from the inside of the center leg part, which is the part most likely to be filled with heat, is radiated through the insertion plate parts The heat is transmitted through 92a to the top plate portion 90a and the side plate portion 91a, from where it can be effectively dissipated to the outside.

[0141] In this embodiment, the cores 21B and 22B in the embodiment shown in FIG. 9 are each divided into two, but the cores 21, 22 shown in FIG. 2B or FIG. 6 may each be divided into two.

[0142] Furthermore, the core 2D shown in Fig. 18 is also a further modified example of the core 2B shown in Fig. 9, and is configured as an assembly of core segments that are separated and divided into core 2D at different division positions and with different division numbers from the first core 21B and second core 22B shown in Fig. 9. 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.

[0143] 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. 9. 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. 9, and a stepped recess 21a2 and an intermediate recess 21a3 are formed.

[0144] 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 together, the second core divided bodies 22B2 have the same configuration as the second core 22B shown in Fig. 9. 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. 9, and a stepped recess 22a2 and an intermediate recess 22a3 are formed.

[0145] 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. 9 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.

[0146] Also in this embodiment, instead of the single heat dissipation plate 9 shown in Fig. 9, 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.

[0147] 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.

[0148] In this embodiment, the core 2B of the embodiment shown in Fig. 9 is divided into six parts, but the core 2 shown in Fig. 2B or Fig. 6 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.

[0149] The present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the present invention. can be modified to.

[0150] For example, in the above-described embodiment, the upper end of the first wire winding portion 40 or the lower end 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.

[0151] 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.

[0152] The spacer 10 is ring-shaped, but may be partially cut out or 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.

[0153] Additionally, the spacer 10 may have any shape or configuration. 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.

[0154] 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.

[0155] 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.

[0156] 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.

[0157] Furthermore, in the above-mentioned embodiment, the terminal blocks 7, 7A, 7B, 7C are directly attached to the cores 2, 2B, 2C, 2D, but they may be attached to the cores via bobbins (not shown). Also, the terminal blocks 7, 7A, 7B, 7C may be attached to the case 8 instead of the cores.

[0158] Moreover, a coil device may be assembled by combining any of the above-described embodiments. [Explanation of symbols]

[0159] 1, 1A, 1B, 1C... 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 5…Second wire 50...Second wire winding section 51a, 51b...Lead section 6…Terminal 60...Terminal base 60a…insertion convex piece 60b...Through hole 61...Connection section 62…External connection part 7,7A,7B,7C…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 70g…Injection hole 70h…Counterbore 71…Mounting groove 71a…insertion groove 71b…Stopper wall 71c…Concave 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

Claims

1. A core including a magnetic material; a wire coiled 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, A coil device in which the terminal block has a mounting groove into which the terminal to which the lead portion of the wire is connected can be inserted from a direction along a first axis that is approximately perpendicular to the winding axis of the wire.

2. 2. The coil device as described in claim 1, wherein the terminal has a connection portion to which the lead portion of the wire is connected, an external connection portion for connecting to an external circuit, and a terminal base portion having an insertion convex piece formed thereon to be inserted into the insertion groove of the mounting groove.

3. 3. The coil device according to claim 2, further comprising a terminal cover attached to the terminal block so as to cover at least the terminal base portion attached to the attachment groove and to expose the external connection portion.

4. The coil device according to claim 3 , wherein the terminal cover has a side piece for covering a connection portion of the terminal.

5. The coil device according to claim 3 , wherein the terminal cover has an injection hole for injecting an adhesive toward the terminal base portion.

6. 6. The coil device according to claim 5, wherein a through hole is formed in the terminal base portion in correspondence with the position of the injection hole.

7. The coil device according to claim 6 , wherein a recess is formed in a bottom surface of the mounting groove at a position corresponding to the through hole.

8. The coil device according to claim 7 , wherein an area of ​​the recess is larger than an area of ​​the through hole of the terminal.

9. 2. The coil device according to claim 1, wherein a recess is formed in a bottom surface of the mounting groove at a position corresponding to the through hole of the terminal.

10. 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.

11. 11. The coil device according to claim 10, wherein the terminal block is provided at one end of the core along the first axis.

12. A core including a magnetic material; a wire coiled 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, the terminal has a connection portion to which the lead portion of the wire is connected, an external connection portion for connection to an external circuit, and a terminal base portion to be attached to the mounting groove of the terminal block; A coil device in which a terminal cover is attached to the terminal block so as to cover at least the terminal base portion and expose the external connection portion.

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

13. 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.

Images