Coil device

Abstract

To provide a coil device with a high bonding quality between a mounting part and a mounting substrate.SOLUTION: A coil device 1 includes: a wire 10 having a winding part 11 and a leading part 12a led from the winding part 11; a core 20 having a core part 21 to which the winding part 11 is provided and a flange part 22a formed to one end of a shaft direction of the core part 21; a mounting part 31 that can be connected to a mounting substrate; a disconnection part 32 connected to the leading part 12a; and a terminal fitting 30a having a coupling part 36 that connects the mounting part 31 with the disconnection part 32. The mounting part 31 and the disconnection part 32 are arranged to a mounting surface 221 of the flange part 22a. The coupling part 36 extends from the mounting part 31 to the disconnection part 32 while passing an end surface 224 of the flange part 22a and a side surface 225 of the flange part 22a.SELECTED DRAWING: Figure 1

Description

[Technical field]

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

[0002] For example, as shown in Patent Document 1, various techniques have been proposed for coil devices having terminal devices. In the coil device of Patent Document 1, the terminal device has a mounting portion and a connecting portion. The mounting portion is a portion that is connected to a land pattern of a mounting board, for example, by soldering. The connecting portion is a portion to which a lead-out portion of a wire is connected, for example, by laser welding. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-074459 A Summary of the Invention [Problem to be solved by the invention]

[0004] Various techniques are known for connecting the lead-out portion to the connection portion, such as soldering, laser welding, thermocompression bonding, and resistance brazing. When the lead-out portion is connected to the connection portion by these techniques, heat is transferred from the connection portion to the mounting portion, causing the temperature of the mounting portion to rise. This can reduce the bonding of the mounting portion to the mounting board, and the bonding strength between the mounting portion and the mounting board. As a result, there is a risk of a mounting defect, such as the coil device coming off the mounting board.

[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 having high bonding quality between a mounting portion and a mounting board. [Means for solving the problem]

[0006] In order to achieve the above object, a coil device according to the present invention comprises: A wire having a winding portion and a lead-out portion led out from the winding portion; a core having a core portion provided with the winding portion and a flange portion formed at one end in an axial direction of the core portion; a terminal device including a mounting portion connectable to a mounting board, a connection portion connected to the lead-out portion, and a coupling portion connecting the mounting portion and the connection portion; the mounting portion and the connecting wire portion are disposed on a mounting surface of the flange portion, The coupling portion extends from the mounting portion to the wire connection portion via an end face of the flange portion and a side surface of the flange portion.

[0007] In the coil device according to the present invention, the connecting portion extends from the mounting portion to the wire connection portion via the end face and the side face of the flange portion. That is, the connecting portion does not extend along the shortest path (path along the mounting surface) connecting the mounting portion and the wire connection portion, but extends along a path that bypasses the shortest path (path via the end face and the side face of the flange portion). Therefore, compared to the case where the connecting portion extends along the shortest path, the length along the extending direction of the connecting portion is longer, and the distance through the connecting portion between the mounting portion and the wire connection portion is longer. This reduces the amount of heat propagated from the wire connection portion to the mounting portion, and the temperature rise of the mounting portion is mitigated. Therefore, the bonding property of the mounting portion to the mounting board is improved, and the bonding quality between the mounting portion and the mounting board can be improved.

[0008] Furthermore, for example, when the mounting part is bonded to the mounting surface of the flange, the temperature rise of the mounting part is mitigated, so that the adhesive layer between the mounting part and the mounting surface of the flange is less likely to deteriorate, thereby improving the bonding of the mounting part to the mounting surface and improving the bonding quality between the mounting part and the mounting surface.

[0009] The flange may have a recess formed on the mounting surface, the mounting portion may be disposed on the mounting surface at a position different from the recess, and the connecting wire portion may be disposed inside the recess. In this case, when the mounting portion is connected to the mounting board, the connecting wire portion is disposed away from the mounting board, making it difficult for the connecting wire portion to come into contact with the mounting board. This makes it possible to prevent short circuits between the connecting wire portion and the mounting board.

[0010] At least a part of the lead-out portion may be disposed between the connection portion and the mounting surface. In this case, for example, when the lead-out portion is connected to the connection portion, the connection portion or the mounting surface can prevent the lead-out portion from shifting in position due to its elasticity. This allows the lead-out portion to be connected to a desired position on the connection portion, improving the joint quality between the lead-out portion and the connection portion.

[0011] The connecting wire portion may have a first pressing piece that presses the draw-out portion toward the mounting surface, and a second pressing piece that is connected to the draw-out portion while pressing the draw-out portion toward the mounting surface on the end face side of the flange portion relative to the first pressing piece. For example, by pressing the draw-out portion toward the mounting surface with the first pressing piece before connecting the draw-out portion to the second pressing piece, the position of the draw-out portion is less likely to vary, and the draw-out portion can be connected to a desired position of the second pressing piece. Furthermore, by pressing the draw-out portion toward the mounting surface with the second pressing piece, the draw-out portion can be connected to the second pressing piece while ensuring contact between the draw-out portion and the second pressing piece.

[0012] The first pressing piece and the second pressing piece may have a crimping structure, in which case the first pressing piece and the second pressing piece can be crimped to easily press the draw-out portion against the mounting surface.

[0013] The connection wire portion may have a terminal groove portion in which at least a part of the lead-out portion is accommodated, and the terminal groove portion may be formed on an inner surface of the connection wire portion facing the mounting surface. In this case, the lead-out portion is positioned by the terminal groove portion, and the position of the lead-out portion relative to the connection wire portion is less likely to vary. This allows the lead-out portion to be connected to a desired position on the connection wire portion, improving the joint quality between the lead-out portion and the connection wire portion.

[0014] The flange may have a flange groove in which at least a part of the lead-out portion is housed, and the flange groove may extend along the mounting surface at a position facing the connection portion. In this case, the flange groove positions the lead-out portion, making it difficult for the position of the lead-out portion to vary relative to the connection portion. This allows the lead-out portion to be connected to a desired position on the connection portion, improving the quality of the connection between the lead-out portion and the connection portion.

[0015] The terminal device may have a first terminal device and a second terminal device, the first terminal device being disposed on one side surface of the flange portion, and the second terminal device being disposed on the other side surface of the flange portion. By providing the flange portion with two terminal devices, the mounting stability of the coil device is improved when the coil device is mounted on a mounting board.

[0016] The coil device may further include a plate-shaped core attached to the core, the plate-shaped core being joined to a non-mounting surface of the flange portion located on the opposite side to the mounting surface. In this case, a closed magnetic circuit is formed by the core and the plate-shaped core, improving the magnetic characteristics of the coil device. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a perspective view of a coil device according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is an exploded perspective view of the coil device shown in FIG. [Diagram 3] FIG. 3 is a perspective view of the core shown in FIG. [Figure 4] FIG. 4 is a perspective view of the terminal shown in FIG. [Diagram 5]FIG. 5 is a side view of the coil device shown in FIG. 1 as viewed from the Y-axis direction. [Figure 6] FIG. 6 is a side view of the coil device shown in FIG. 1 as viewed from the X-axis direction. [Figure 7] FIG. 7 is a perspective view of a coil device according to the second embodiment of the present invention. [Figure 8] FIG. 8 is a perspective view of the terminal shown in FIG. [Figure 9] FIG. 9 is an exploded perspective view of a coil device according to a third embodiment of the present invention. [Figure 10] FIG. 10 is a perspective view of the core shown in FIG. [Figure 11] FIG. 11 is a perspective view of a coil device according to a fourth embodiment of the present invention. [Figure 12] FIG. 12 is a perspective view of the core shown in FIG. [Figure 13] FIG. 13 is a perspective view of the terminal shown in FIG. [Figure 14] FIG. 14 is a perspective view of a coil device according to a fifth embodiment of the present invention. [Figure 15] FIG. 15 is a perspective view of the terminal shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 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. Furthermore, the present invention is not limited to the following embodiments.

[0019] First embodiment 1 functions as, for example, an inductor, and can be mounted on a power supply for an electric device. The coil device 1 has a wire 10, a core 20, and terminals 30a and 30b. In addition to these components, the coil device 1 has a plate-shaped core 50, but the plate-shaped core 50 is not essential.

[0020] As shown in Fig. 2, the wire 10 has a winding portion 11 wound into a coil shape, and lead-out portions 12a and 12b led out from the winding portion 11. The wire 10 is, but is not limited to, an insulating coated wire in which a copper wire or the like is coated with an insulating coating 13. The wire diameter of the wire 10 is, but is not limited to, 10 to 300 µm, for example. The coating 13 is removed from the tip end of each of the lead-out portions 12a and 12b.

[0021] The core 20 is a drum core and has a core portion 21 and flange portions 22a and 22b. The core 20 is a magnetic body and is composed of a ferrite composition, a metal composition, or a composite composition of these with a resin. The wire 10 is wound around the outer circumferential surface of the core portion 21 to form the winding portion 11. A gap is formed between the end of the winding portion 11 in the winding axis direction and the flange portion 22a. In addition, a gap is formed between the end of the winding portion 11 in the winding axis direction and the flange portion 22b. As shown in FIG. 3, the cross-sectional shape of the core portion 21 perpendicular to the axial direction is octagonal, but may be a square, hexagon, other polygonal, circular, elliptical, or the like.

[0022] Flange portion 22a is formed at one axial end of core portion 21, and flange portion 22b is formed at the other axial end of core portion 21. Flange portions 22a and 22b each have a mounting surface 221, a non-mounting surface 222, an inner end surface 223, an outer end surface 224, a first side surface 225, and a second side surface 226. Mounting surface 221 and non-mounting surface 222 face each other, inner end surface 223 and outer end surface 224 face each other, and first side surface 225 and second side surface 226 face each other.

[0023] 2 etc., the X-axis is an axis along the direction in which the inner end surface 223 and the outer end surface 224 face each other. The Y-axis is an axis along the direction in which the first side surface 225 and the second side surface 226 face each other. The Z-axis is an axis along the direction in which the mounting surface 221 and the non-mounting surface 222 face each other. The X-axis, Y-axis and Z-axis are mutually perpendicular. The X-axis corresponds to the axial direction of the core portion 21.

[0024] The flange portions 22a and 22b have a recess 25 formed in the mounting surface 221. The recess 25 is formed on the side of the mounting surface 221 that is close to the first side surface 225. The mounting surface 221 is cut out by the recess 25 on the side that is close to the first side surface 225. The depth of the recess 25 is not particularly limited, but is a depth that can accommodate a wire connection portion 32 of the terminal device 30a or 30b described later.

[0025] The mounting surface 221 has a first region 23 which is a region where the recess 25 is not formed, and a second region 24 which is a region where the recess 25 is formed. The first region 23 and the second region 24 are both flat surfaces and adjacent to each other along the Y axis. The length of the first region 23 in the Y axis direction is longer than the length of the second region 24 in the Y axis direction, but may be equal to or shorter than this.

[0026] A step is formed along the Z axis between the first region 23 and the second region 24. A step forming surface 29 connecting the first region 23 and the second region 24 extends from one end to the other end in the X axis direction of the mounting surface 221. A notch (chamfer) 26 is formed on the outer edge of each of the first region 23 and the second region 24 to prevent cracking or chipping.

[0027] The recess 25 of the flange 22a and the recess 25 of the flange 22b are located on opposite sides of each other in the Y-axis direction with respect to the core 21. Therefore, when the coil device 1 is mounted on a mounting board (not shown), the stability of the coil device 1 with respect to the mounting board is improved compared to a case in which the recess 25 of the flange 22a and the recess 25 of the flange 22b are located on the same side in the Y-axis direction with respect to the core 21. Note that the recess 25 of the flange 22a and the recess 25 of the flange 22b may be located on the same side in the Y-axis direction with respect to the core 21.

[0028] As shown in FIG. 4, the terminal device 30a has a mounting portion 31, a connecting portion 32, and a connecting portion 36. The terminal device 30b has a mounting portion 31, a connecting portion 32, and a connecting portion 36. The terminal device 30a and the terminal device 30b have the same shape, but may have different shapes. The terminal devices 30a and 30b are made of a conductor such as a metal. A plating film of Sn, Ni, or the like is formed on the entire surface or locally on the surfaces of the terminal devices 30a and 30b. The thickness of each of the terminal devices 30a and 30b is not particularly limited, but is 50 to 300 μm. The plate thickness of each of the mounting portion 31, the connecting portion 32, and the connecting portion 36 is the same, but may be different.

[0029] The mounting portion 31 is a portion that can be connected to a mounting board. The mounting portion 31 has a surface parallel to the first region 23 of the mounting surface 221 (FIG. 3). As shown in FIG. 1, the mounting portion 31 is disposed in the first region 23. That is, the mounting portion 31 is disposed on the mounting surface 221 at a position different from the recess 25.

[0030] With the terminal devices 30a and 30b fixed to the flange portions 22a and 22b, respectively, the mounting portion 31 is adhered to the first region 23 (FIG. 3) by an adhesive (e.g., an epoxy adhesive). This forms an adhesive layer between the mounting portion 31 and the first region 23, making it possible to prevent the terminal devices 30a and 30b from coming off. The mounting portion 31 may be connected to a land pattern of a mounting board by solder, a conductive adhesive, or the like.

[0031] The length of the mounting portion 31 in the Y-axis direction is not particularly limited, but the mounting surface 221 improves the stability of the coil device 1 relative to the mounting board.

[0032] The connecting wire portion 32 is a portion that is connected to the lead-out portion 12a or 12b. The lead-out portion 12a may be connected to the connecting wire portion 32 by soldering, laser welding, thermocompression bonding, ultrasonic bonding, resistance brazing, ultraviolet curing resin bonding, or the like. The same applies to the lead-out portion 12b.

[0033] In this embodiment, the lead-out portions 12a and 12b are connected to the connecting portion 32 by laser welding. Therefore, as shown in Fig. 1, a fusion portion (weld ball) 40 is formed at the connection portion between the connecting portion 32 of the terminal device 30a and the lead-out portion 12a. Also, a fusion portion 40 is formed at the connection portion between the connecting portion 32 of the terminal device 30b and the lead-out portion 12b. The lead-out portions 12a and 12b are integrated with the connecting portion 32 by the fusion portion 40.

[0034] At least a part of the connecting wire part 32 is disposed in the second region 24 (FIG. 3) of the mounting surface 221. At least a part of the connecting wire part 32 is disposed inside the recess 25. Therefore, when the mounting portion 31 is connected to the mounting board, the connecting wire part 32 is disposed away from the mounting board, and the connecting wire part 32 is less likely to come into contact with the mounting board. This makes it possible to prevent a short circuit between the connecting wire part 32 and the mounting board. Although a part of the connecting wire part 32 is disposed on the first side surface 225, the whole of the connecting wire part 32 may be disposed in the second region 24. The connecting wire part 32 is not bonded to the second region 24 by an adhesive, and a gap is formed between the connecting wire part 32 and the second region 24.

[0035] As shown in Fig. 4, the connecting portion 32 has a first pressing piece 33, a second pressing piece 34, and a groove portion 35 formed between the first pressing piece 33 and the second pressing piece 34. The first pressing piece 33 and the second pressing piece 34 are located on opposite sides of each other with the groove portion 35 interposed therebetween. The first pressing piece 33 is located on the side of the inner end surface 223 (Fig. 3) of each of the flange portions 22a and 22b. The second pressing piece 34 is located on the side of the outer end surface 224 (Fig. 3) of each of the flange portions 22a and 22b.

[0036] The first pressing piece 33 and the second pressing piece 34 are configured to be bendable and have a crimped structure. In Fig. 4, the state of the first pressing piece 33 before bending is shown by a solid line, and the state of the first pressing piece 33 after bending is shown by a two-dot chain line. The state of the second pressing piece 34 before bending is shown by a solid line, and the state of the second pressing piece 34 after bending is shown by a two-dot chain line.

[0037] The first pressing piece 33 is made of a plate piece having an elongated shape, and is configured to be bent at approximately a right angle from a state in which it stands up along the Z axis. The second pressing piece 34 is made of a plate piece having an L-shape, and is configured to be bent at approximately a right angle from a state in which it stands up along the Z axis. As shown in FIG. 1, the first pressing piece 33 is disposed in parallel to the second region 24 (FIG. 3) in a bent state. Also, the second pressing piece 34 is disposed in parallel to the second region 24 in a bent state.

[0038] 4, the second pressing piece 34 has an extension portion 340. The extension portion 340 is formed at the tip portion of the second pressing piece 34, and the length of the extension portion 340 along the X-axis is longer than the length of the other portions along the X-axis.

[0039] 1 and 5, at least a portion of lead-out portion 12a is disposed between connecting wire portion 32 and second region 24 (FIG. 3) of mounting surface 221, and is sandwiched (held) by connecting wire portion 32 and mounting surface 221. A gap is formed between connecting wire portion 32 and second region 24, and at least a portion of lead-out portion 12a is disposed inside the gap.

[0040] At least a portion of lead-out portion 12b is disposed between connecting wire portion 32 and second region 24 of mounting surface 221, and is sandwiched (held) by connecting wire portion 32 and second region 24. A gap is formed between connecting wire portion 32 and second region 24, and at least a portion of lead-out portion 12b is disposed inside the gap.

[0041] The first pressing piece 33 has a crimping structure and presses the drawn-out portion 12a or 12b toward the mounting surface 221. The second pressing piece 34 has a crimping structure and presses the drawn-out portion 12a or 12b toward the mounting surface 221 on the outer end surface 224 side of the first pressing piece 33. By crimping the first pressing piece 33 and the second pressing piece 34, the drawn-out portion 12a or 12b can be easily pressed toward the mounting surface 221. The drawn-out portion 12a or 12b may be in contact with the second region 24 of the mounting surface 221, or a gap may be formed between the drawn-out portion 12a or 12b and the mounting surface 221.

[0042] The drawn-out portion 12a or 12b is in contact with the inner surface of the second pressing piece 34 (the surface facing the mounting surface 221). The drawn-out portion 12a or 12b is connected to the extension portion 340 of the second pressing piece 34 by, for example, laser welding. The fused portion 40 is formed in the second pressing piece 34 (extension portion 340), but is not formed in the first pressing piece 33. Although the drawn-out portion 12a or 12b is in contact with the inner surface of the first pressing piece 33 (the surface facing the mounting surface 221), it is not integrated with the first pressing piece 33 by the fused portion 40.

[0043] For example, by pressing down the drawn-out portion 12a toward the mounting surface 221 with the first pressing piece 33 before connecting the drawn-out portion 12a to the second pressing piece 34, the position of the drawn-out portion 12a is less likely to vary, and the drawn-out portion 12a can be connected to the desired position of the second pressing piece 34. Furthermore, by pressing down the drawn-out portion 12a toward the mounting surface 221 with the second pressing piece 34, the drawn-out portion 12a can be connected to the second pressing piece 34 while ensuring contact between the drawn-out portion 12a and the second pressing piece 34. The same applies to the drawn-out portion 12b.

[0044] 4, the connecting portion 36 is a portion that connects the mounting portion 31 and the connection portion 32. One end of the connecting portion 36 in the extending direction is continuously connected to the outer end portion in the X-axis direction of the mounting portion 31. The other end of the connecting portion 36 in the extending direction is continuously connected to each end portion (root) of the first pressing piece 33 and the second pressing piece 34.

[0045] As shown in FIG. 3 and FIG. 4, the connecting portion 36 is bent in an L-shape at the intersection (ridge line) between the first side surface 225 and the outer end surface 224, and has an L-shape (bent structure) in a plan view. The connecting portion 36 has a side surface facing portion 361 and an end surface facing portion 362 perpendicular to the side surface facing portion 361. As shown in FIG. 5, the side surface facing portion 361 is disposed on the first side surface 225 so as to face the first side surface 225. The side surface facing portion 361 is in contact with the first side surface 225, but a gap may be formed between the side surface facing portion 361 and the first side surface 225. The length of the side surface facing portion 361 along the Z axis is not particularly limited, but is equal to or less than half the length of the first side surface 225 along the Z axis.

[0046] The first pressing piece 33 and the second pressing piece 34 extend upward from one end in the Z-axis direction of the side surface facing portion 361. No adhesive is filled between the side surface facing portion 361 and the first side surface 225.

[0047] 6, the end face facing portion 362 is disposed on the outer end surface 224 so as to face the outer end surface 224. The end face facing portion 362 has an L-shape (bent structure) when viewed from the X-axis direction. The end face facing portion 362 is in contact with the outer end surface 224, but a gap may be formed between the end face facing portion 362 and the outer end surface 224. In addition, the end face facing portion 362 (particularly, a wide portion 362w described later) may be adhered to the outer end surface 224 by an adhesive.

[0048] The end surface opposing portion 362 has a wide portion 362w and a narrow portion 362n. One end of the wide portion 362w in the Z-axis direction is continuously connected to the mounting portion 31 (FIG. 4). The length L1 of the wide portion 362w in the Z-axis direction is longer than the length L2 of the narrow portion 362n in the Z-axis direction. The area of ​​the wide portion 362w is larger than the area of ​​the narrow portion 362n. The ratio L1 / L2 of L1 to L2 is not particularly limited, but is 2 or more. The length L1 of the wide portion 362w in the Z-axis direction is not particularly limited, but is ½ or more of the length of the outer end surface 224 in the Z-axis direction.

[0049] The length L3 of the wide portion 362w along the Y axis is longer than the length L4 of the narrow portion 362n along the Y axis. The ratio L3 / L4 of L3 to L4 is not particularly limited, but is equal to or greater than 1. Furthermore, the length L3 of the wide portion 362w in the Y axis direction is not particularly limited, but is equal to or greater than 1 / 2 of the length of the outer end surface 224 in the Y axis direction.

[0050] The narrow portion 362n is adjacent to the wide portion 362w and extends along the Y axis. The narrow portion 362n continuously connects the wide portion 362w and the side surface facing portion 361 (FIG. 4). The narrow portion 362n is located on the outer end surface 224 closer to the non-mounting surface 222 than the second region 24.

[0051] As shown in Fig. 5 and Fig. 6, the connecting portion 36 extends from the mounting portion 31 to the connecting portion 32 via two faces of the flange portion 22a, i.e., the outer end face 224 and the first side face 225. The connecting portion 36 has a structure in which it is bent in an L-shape from the wide portion 362w to the narrow portion 362n, and also bent in an L-shape from the narrow portion 362n to the side face facing portion 361. In this way, the connecting portion 36 is bent at two places, but may be bent at three or more places. For example, in the example shown in Fig. 6, the end face facing portion 362 is bent at one place on the outer end face 224, but may be bent at two or more places.

[0052] When the coil device 1 is mounted on a mounting board, a fillet of solder, conductive adhesive, or the like may be formed on the connecting portion 36. In this case, the fillet can reinforce the connection between the mounting portion 31 and the mounting board.

[0053] As shown in FIG. 5, the drawn-out portion 12a is drawn out from the core portion 21 to the outer end surface 224. The same is true for the drawn-out portion 12b. The fusion zone 40 is formed at the end of the extension portion 340 in the X-axis direction, and a part of the fusion zone 40 is located outside the outer end surface 224 in the X-axis direction. This is because, when the drawn-out portion 12a or 12b is connected to the connecting portion 32, the laser is irradiated to the connecting portion 32 (the second pressing piece 34) outside the outer end surface 224 in the X-axis direction. In this case, it is possible to prevent damage to the flange portion 22a or 22b during the laser irradiation.

[0054] As shown in FIG. 2, the plate core 50 is a plate having a rectangular parallelepiped shape, and is attached to the core 20. The plate core 50 is made of the same material as the core 20, but may be made of a material different from that of the core 20. As shown in FIG. 1, the plate core 50 is bonded to the non-mounting surfaces 222 of the flanges 22a and 22b by adhesive. A notch (chamfer) is formed on the outer edge of the plate core 50 to prevent cracking or chipping. By attaching the plate core 50 to the core 20, a closed magnetic circuit consisting of the core 20 and the plate core 50 is formed, and the magnetic characteristics of the coil device 1 are improved.

[0055] Next, a method for manufacturing the coil device 1 will be described. First, the wire 10, the core 20, and the terminal devices 30a and 30b shown in Fig. 2 are prepared. For example, the length of the core 20 in the X-axis direction is 1 to 6 mm, the length of the core 20 in the Y-axis direction is 0.5 to 3 mm, and the length of the core 20 in the Z-axis direction is 0.5 to 3 mm, but the size of the core 20 is not particularly limited.

[0056] Next, the mounting portion 31 of the terminal device 30a is bonded to the flange portion 22a with an adhesive, and the terminal device 30b is attached to the flange portion 22a. Also, the mounting portion 31 of the terminal device 30b is bonded to the flange portion 22b with an adhesive, and the terminal device 30b is attached to the flange portion 22b. At this time, as shown in Fig. 4, the first pressing piece 33 and the second pressing piece 34 are raised. Next, as shown in Fig. 2, the wire 10 is wound around the core portion 21 to form the winding portion 11.

[0057] Next, one side of the wire 10 is drawn from the core 21 to the outer end surface 224 of the flange 22a so as to pass over the second region 24 of the flange 22a. Then, the first pressing piece 33 shown in FIG. 4 is bent at a right angle, and the first pressing piece 33 presses one side of the wire 10 toward the mounting surface 221. Next, one side of the wire 10 is cut by a cutter outside the outer end surface 224 in the X-axis direction. Next, the second pressing piece 34 shown in FIG. 4 is bent at a right angle, and the second pressing piece 34 presses one end of the wire 10 toward the mounting surface 221. Also, at an appropriate timing, the coating 13 on one end of the wire 10 is peeled off.

[0058] Similarly, the other side of the wire 10 is drawn from the core 21 to the outer end surface 224 of the flange 22b so as to pass over the second region 24 of the flange 22b. Then, the first pressing piece 33 shown in FIG. 4 is bent at a right angle, and the other side of the wire 10 is pressed toward the mounting surface 221 by the first pressing piece 33. Next, the other side of the wire 10 is cut by a cutter outside the outer end surface 224 in the X-axis direction. Next, the second pressing piece 34 shown in FIG. 4 is bent at a right angle, and the other end of the wire 10 is pressed toward the mounting surface 221 by the second pressing piece 34. Also, at an appropriate timing, the coating 13 on the other end of the wire 10 is peeled off.

[0059] Next, as shown in Fig. 5, a laser is irradiated toward the extension portion 340 of the terminal device 30a, and the lead portion 12a is connected to the extension portion 340. Similarly, a laser is irradiated toward the extension portion 340 of the terminal device 30b, and the lead portion 12b is connected to the extension portion 340. Note that the extension portion 340 is shortened in length in the X-axis direction by being melted (by forming the melted portion 40). Next, the plate-shaped core 50 is bonded to the non-mounting surface 222 of each of the flange portions 22a and 22b with an adhesive. In this manner, the coil device 1 can be manufactured.

[0060] As shown in FIG. 1, in the coil device 1 of this embodiment, the connecting portion 36 extends from the mounting portion 31 to the connecting portion 32 via the outer end surface 224 and the first side surface 225 of the flange portion 22a. That is, the connecting portion 36 does not extend along the shortest path (path along the mounting surface 221) connecting the mounting portion 31 and the connecting portion 32, but extends along a path that bypasses the shortest path (path via the outer end surface 224 and the first side surface 225 of the flange portion 22a). Therefore, compared to the case where the connecting portion 36 extends along the shortest path, the length along the extending direction of the connecting portion 36 is longer, and the distance through the connecting portion 36 between the mounting portion 31 and the connecting portion 32 is longer. As a result, when the drawing portion 12a is laser-welded to the connecting portion 32, the amount of heat propagated from the connecting portion 32 to the mounting portion 31 is reduced, and the temperature rise of the mounting portion 31 is mitigated. As a result, the plating film on the surface of the mounting portion 31 is less likely to deteriorate, the bonding of the mounting portion 31 to the mounting board is improved, and the bonding quality between the mounting portion 31 and the mounting board can be improved.

[0061] Furthermore, by mitigating the temperature rise of the mounting portion 31, the adhesive between the mounting portion 31 and the mounting surface 221 is less likely to deteriorate. This improves the bonding of the mounting portion 31 to the mounting surface 221, and the bonding quality between the mounting portion 31 and the mounting surface 221 can be improved.

[0062] Furthermore, at least a portion of lead-out portion 12a is disposed between connecting wire portion 32 and mounting surface 221. Therefore, when connecting lead-out portion 12a to connecting wire portion 32, displacement of lead-out portion 12a due to its elasticity can be prevented by connecting wire portion 32 or mounting surface 221. This allows lead-out portion 12a to be connected to a desired position on connecting wire portion 32, improving the joint quality between lead-out portion 12a and connecting wire portion 32.

[0063] Second embodiment 7 has the same configuration as the coil device 1 of the first embodiment, except for the following points. The same reference numerals are given to the parts that overlap with the coil device 1 of the first embodiment, and detailed description thereof will be omitted.

[0064] The coil device 1A differs from the coil device 1 of the first embodiment in that the coil device 1A has terminal devices 30aA and 30bA. The terminal devices 30aA and 30bA differ from the terminal portions 30a and 30b of the first embodiment in that the terminal devices 30aA and 30bA have a connecting portion 32A.

[0065] 8, the connecting wire portion 32A has a terminal groove portion 37. The terminal groove portion 37 is formed on the inner surface 321 of each of the first pressing piece 33 and the second pressing piece 34, and is recessed from the inner surface 321 toward the outer surface 322. However, the inner surface 321 is the surface facing the mounting surface 221, and the outer surface 322 is the surface opposite the inner surface 321.

[0066] The terminal groove 37 extends along the X-axis. More specifically, the terminal groove 37 extends linearly from one end to the other end of the first pressing piece 33 in the X-axis direction. The terminal groove 37 also extends linearly from one end to the other end of the second pressing piece 34 in the X-axis direction. The cross-sectional shape of the terminal groove 37 is rectangular, but may be other polygonal, circular, elliptical, etc.

[0067] The depth of the terminal groove 37 is smaller than the diameter of the wire 10. However, the depth of the terminal groove 37 may be equal to or larger than the diameter of the wire 10. As shown in Fig. 7, at least a portion of the lead-out portion 12a is accommodated in the terminal groove 37 of the terminal device 30aA. Also, at least a portion of the lead-out portion 12b is accommodated in the terminal groove 37 of the terminal device 30bA.

[0068] In this embodiment, the same effects as those in the first embodiment can be obtained. In addition, in this embodiment, at least a part of the lead-out portion 12a is housed in the terminal groove portion 37, so that the lead-out portion 12a is positioned by the terminal groove portion 37, and the position of the lead-out portion 12a relative to the connecting wire portion 32A is less likely to vary. This allows the lead-out portion 12a to be connected to a desired position of the connecting wire portion 32A, and improves the joint quality between the lead-out portion 12a and the connecting wire portion 32A.

[0069] Third embodiment 9 has a similar configuration to the coil device 1 of the first embodiment, except for the following points. The same reference numerals are given to parts that overlap with the coil device 1 of the first embodiment, and detailed descriptions thereof will be omitted.

[0070] The coil device 1B differs from the coil device 1 of the first embodiment in that it has a core 20B. The core 20B differs from the core 20 of the first embodiment in that it has flange portions 22aB and 22bB.

[0071] 10, flange portions 22aB and 22bB have flange groove portions 27. Flange groove portions 27 are formed in second region 24 of mounting surface 221 and extend along mounting surface 221 at positions facing connecting portion 32 (first pressing piece 33 and second pressing piece 34) shown in FIG.

[0072] Flange groove portion 27 extends linearly along the X-axis from one end to the other end in the X-axis direction of mounting surface 221. The cross-sectional shape of flange groove portion 27 is rectangular, but may be other polygonal, circular, elliptical, or the like.

[0073] The depth of flange groove portion 27 is smaller than the diameter of wire 10. However, the depth of flange groove portion 27 may be equal to or larger than the diameter of wire 10. As shown in Fig. 9, at least a portion of lead-out portion 12a is housed in flange groove portion 27 of flange portion 22aB. Also, at least a portion of lead-out portion 12b is housed in flange groove portion 27 of flange portion 22bB.

[0074] In this embodiment, the same effects as those in the first embodiment can be obtained. In addition, in this embodiment, at least a portion of the lead-out portion 12a is housed in the flange groove portion 27. Therefore, the lead-out portion 12a is positioned by the flange groove portion 27, and the position of the lead-out portion 12a relative to the connecting portion 32 is less likely to vary. This allows the lead-out portion 12a to be connected to a desired position of the connecting portion 32, and improves the joint quality between the lead-out portion 12a and the connecting portion 32.

[0075] Fourth embodiment The coil device 1C of the fourth embodiment shown in Fig. 11 has a similar configuration to the coil device 1 of the first embodiment, except for the following points. The same reference numerals are given to the parts that overlap with the coil device 1 of the first embodiment, and detailed descriptions thereof will be omitted.

[0076] The coil device 1C has a core 20C, terminal devices 30aC_1 and 30aC_2, and terminal devices 30bC_1 and 30bC_2. The coil device 1C further has a wire 60 in addition to the wire 10. The coil device 1C functions as, for example, a transformer and can be mounted on a power source of an electric device. One of the wires 10 and 60 constitutes a primary coil, and the other of the wires 10 and 60 constitutes a secondary coil.

[0077] The wire 60 has a winding portion 61 wound in a coil shape, and drawn-out portions 62a and 62b drawn out from the winding portion 61. Although detailed illustration is omitted, the wire 10 is wound around the outer peripheral surface of the core portion 21 of the core 20C, and the winding portion 11 is formed on the outer peripheral surface of the core portion 21 (see FIG. 2). The wire 60 is wound around the outer peripheral surface of the winding portion 11, and the winding portion 61 is formed on the outer peripheral surface of the winding portion 11. However, the winding manner of the wires 10 and 60 is not limited to this, and for example, the wire 10 may be wound around one side of the core portion 21 in the X-axis direction, and the wire 60 may be wound around the other side of the core portion 21 in the X-axis direction.

[0078] 12, the core 20C has flanges 22aC and 22bC. The flanges 22aC and 22bC have recesses 25_1 and 25_2 and a protrusion 28. The recess 25_1 is formed at one end of the mounting surface 221 in the Y-axis direction, and the one end of the mounting surface 221 in the Y-axis direction is cut out by the recess 25_1. The recess 25_2 is formed at the other end of the mounting surface 221 in the Y-axis direction, and the other end of the mounting surface 221 in the Y-axis direction is cut out by the recess 25_2.

[0079] The protrusion 28 is formed in the center of the outer end surface 224 in the Y-axis direction, and extends along the Z-axis. The protrusion 28 protrudes outward from the outer end surface 224 along the X-axis. The protrusion length of the protrusion 28 is not particularly limited, but is greater than the thickness of the terminal device 30aC_1 (FIG. 11). However, the protrusion length of the protrusion 28 may be equal to or less than the thickness of the terminal device 30aC_1. A notch (chamfered portion or taper) is formed in the protrusion 28 along the Z-axis to prevent cracking or chipping.

[0080] 11, the protrusion 28 of the flange portion 22aC separates the terminal fittings 30aC_1 and 30aC_2, thereby insulating the terminal fittings 30aC_1 and 30aC_2 from each other. Also, the protrusion 28 of the flange portion 22bC separates the terminal fittings 30bC_1 and 30bC_2 from each other, thereby insulating the terminal fittings 30bC_1 and 30bC_2 from each other.

[0081] The terminal device 30aC_1 is disposed on the first side surface 225 side of the flange portion 22aC, and the terminal device 30aC_2 is disposed on the second side surface 226 side of the flange portion 22aC. Moreover, the terminal device 30bC_1 is disposed on the first side surface 225 side of the flange portion 22bC, and the terminal device 30bC_2 is disposed on the second side surface 226 side of the flange portion 22bC.

[0082] As shown in FIG. 13, the terminal devices 30aC_1 and 30aC_2 and the terminal devices 30bC_1 and 30bC_2 have a connecting portion 36C. The connecting portion 36C has a side surface facing portion 361C, and the side surface facing portion 361C has a side surface rising portion 363. The side surface rising portion 363 is a portion of the side surface facing portion 361C that is located closer to the mounting surface 221 (FIG. 12) than the narrow width portion 362n. In other words, the side surface rising portion 363 is a portion that extends perpendicularly to the narrow width portion 362n. The length of the connecting portion 36C along the extension direction is longer by the length of the side surface facing portion 361C along the Z axis.

[0083] In this embodiment, the length along the Y axis of the mounting portion 31 is shorter than the length along the Y axis of the mounting portion 31 of the first embodiment. Also, the length along the Y axis of the wide portion 362w is shorter than the length along the Y axis of the wide portion 362w of the first embodiment. Also, the length along the Z axis of the wide portion 362w is longer than the length along the Z axis of the wide portion 362w of the first embodiment.

[0084] 11, the lead-out portion 12a is connected to the connecting portion 32 of the terminal device 30aC_1, and the lead-out portion 12b is connected to the connecting portion 32 of the terminal device 30bC_1. The lead-out portion 62a is connected to the connecting portion 32 of the terminal device 30aC_2, and the lead-out portion 62b is connected to the connecting portion 32 of the terminal device 30bC_2.

[0085] In this embodiment, the same effects as those in the first embodiment can be obtained. In addition, in this embodiment, the flange portion 22aC is provided with two terminal devices 30aC_1 and 30aC_2, and the flange portion 22bC is provided with two terminal devices 30bC_1 and 30bC_2. Therefore, when the coil device 1C is mounted on a mounting board, the mounting stability of the coil device 1 is improved.

[0086] In addition, the side surface rising portion 363 is added to the side surface facing portion 361C, so that the length of the connecting portion 36C along the extending direction is increased accordingly. Therefore, the distance between the mounting portion 31 and the connecting portion 32 through the connecting portion 36C is increased, and when the lead-out portion 12a is laser-welded to the connecting portion 32, the amount of heat propagated from the connecting portion 32 to the mounting portion 31 is reduced. In addition, when the lead-out portion 62a is laser-welded to the connecting portion 32, the amount of heat propagated from the connecting portion 32 to the mounting portion 31 is reduced. This reduces the temperature rise of the mounting portion 31, makes the plating film on the surface of the mounting portion 31 less likely to deteriorate, and improves the bonding of the mounting portion 31 to the mounting board. In addition, the adhesive between the mounting portion 31 and the mounting surface 221 is less likely to deteriorate, and improves the bonding of the mounting portion 31 to the mounting surface 221.

[0087] Fifth embodiment The coil device 1D of the fifth embodiment shown in Fig. 14 has a similar configuration to the coil device 1 of the first embodiment, except for the following points. The same reference numerals are given to the parts that overlap with the coil device 1 of the first embodiment, and detailed descriptions thereof will be omitted.

[0088] The coil device 1D differs from the coil device 1 of the first embodiment in that it has terminal devices 30aD and 30bD. As shown in FIG. 15, the terminal devices 30aD and 30bD differ from the terminal devices 30a and 30b of the first embodiment in that it has a connecting portion 32D. The connecting portion 32D is a plate parallel to the mounting surface 221, and does not have the first pressing piece 33 and the second pressing piece 34 (FIG. 4). That is, the connecting portion 32D is the connecting portion 32 of the first embodiment (FIG. 4) without the groove portion 35. In FIG. 15, the shape of the connecting portion 32D after laser welding is shown by a solid line, and the shape of the connecting portion 32D before laser welding is shown by a dashed line.

[0089] As shown in Fig. 14, the lead-out portion 12a is drawn out linearly along the X-axis on the outer surface 322 of the connecting wire portion 32D of the terminal device 30aD. The lead-out portion 12a is connected to the outer surface 322 at the outer end of the connecting wire portion 32D in the X-axis direction by, for example, laser welding. The lead-out portion 12b is drawn out linearly along the X-axis on the outer surface 322 of the connecting wire portion 32D of the terminal device 30bD. The lead-out portion 12b is connected to the outer surface 322 at the outer end of the connecting wire portion 32D in the X-axis direction by, for example, laser welding.

[0090] In this embodiment, the same effects as in the first embodiment can be obtained. In addition, when the lead-out portion 12a is connected to the outer surface 322 of the connecting portion 32D as in this embodiment, the process of connecting the lead-out portion 12a to the connecting portion 32D is easy.

[0091] The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present invention.

[0092] For example, in the first embodiment, the side rising portion 363 (FIG. 13) of the fourth embodiment may be added to the side facing portion 361 of each of the terminal devices 30a and 30b shown in FIG. 4. The same applies to the second, third and fifth embodiments. In this case, the length of the connecting portion 36 along the extending direction is increased, and the distance through the connecting portion 36 between the mounting portion 31 and the connecting portion 32 is increased. This reduces the amount of heat transmitted from the connecting portion 32 to the mounting portion 31, and further mitigates the temperature rise of the mounting portion 31. Therefore, the effect described in the first embodiment can be effectively obtained.

[0093] The techniques of the second, third and fifth embodiments may be applied to the fourth embodiment.

[0094] In the first embodiment, as shown in Fig. 1, the connecting portion 36 extends from the mounting portion 31 toward the positive side of the Y-axis, but may extend from the mounting portion 31 toward the negative side of the Y-axis as in the terminal device 30aC_2 in Fig. 13. The same applies to the second, third and fifth embodiments.

[0095] In the first embodiment, the connecting wire portion 32 has two pressing pieces, the first pressing piece 33 and the second pressing piece 34, but may have a single pressing piece. The same applies to the second to fourth embodiments.

[0096] In the above-described fourth embodiment, the coil device 1C may be provided with a plate-shaped core 50. [Explanation of symbols]

[0097] 1, 1A, 1B, 1C, 1D... Coil device 10,60…Wire 11,61…Winding section 12a, 12b, 62a, 62b...Drawer part 13...Coating 20, 20B, 20C...Core 21…core part 22a,22b,22aB,22bB,22aC,22bC...Trim part 221...Mounting surface 222...Non-mounting surface 223…Inner end surface 224...Outer end surface 225…1st side 226…Second side 23...First area 24,24_1,24_2…Second area 25, 25_1, 25_2…Concave 26…Notch 27…Tsuba groove part 28…Convex part 29...Step forming surface 30a,30b,30a_1,30a_2,30b_1,30b_2,30aA,30bA,30aD,30bD…Terminal fitting 31…Mounting section 32,32A,32D…Connection part 321…Inside 322…External surface 33…First clamp piece 34…Second clamp piece 340…Extension 35…Groove 36,36C…Connection part 361,361C…Side facing part 362…End face opposing part 362w…Wide section 362n…Narrow part 363…Side elevation part 37…Terminal groove 40…Melted part 50…Plate core

Claims

1. A wire having a winding portion and a lead-out portion led out from the winding portion; a core having a core portion provided with the winding portion and a flange portion formed at one end in an axial direction of the core portion; a terminal device including a mounting portion connectable to a mounting board, a connection portion connected to the lead-out portion, and a coupling portion connecting the mounting portion and the connection portion; the mounting portion and the connecting wire portion are disposed on a mounting surface of the flange portion, The coupling portion extends from the mounting portion to the connection portion via an end face of the flange portion and a side face of the flange portion.

2. The flange portion has a recess formed on the mounting surface, the mounting portion is disposed on the mounting surface at a position different from the recess; The coil device according to claim 1 , wherein the connection portion is disposed inside the recess.

3. The coil device according to claim 1 , wherein at least a portion of the lead-out portion is disposed between the connection portion and the mounting surface.

4. 3. The coil device according to claim 1, wherein the connection wire portion has a first pressing piece that presses the pull-out portion toward the mounting surface, and a second pressing piece that is connected to the pull-out portion while pressing the pull-out portion toward the mounting surface on the end face side of the flange portion relative to the first pressing piece.

5. The coil device according to claim 4 , wherein the first pressing piece and the second pressing piece have a crimping structure.

6. the connecting wire portion has a terminal groove portion in which at least a portion of the drawn-out portion is accommodated, The coil device according to claim 1 , wherein the terminal groove portion is formed on an inner surface of the wire connection portion that faces the mounting surface.

7. The flange portion has a flange groove portion in which at least a portion of the pull-out portion is accommodated, The coil device according to claim 1 , wherein the flange groove portion extends along the mounting surface at a position opposite to the wire connection portion.

8. The terminal device includes a first terminal device and a second terminal device, The first terminal device is disposed on one side surface of the flange portion, 3. The coil device according to claim 1, wherein the second terminal device is disposed on the other side surface of the flange portion.

9. Further, a plate-shaped core is attached to the core, The coil device according to claim 1 or 2, wherein the plate-shaped core is joined to a non-mounting surface of the flange portion located on the opposite side to the mounting surface.

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