Coil device

Abstract

The invention provides a coil device capable of preventing short circuit failure during installation. A coil device (1) is provided with: a core having a mounting surface (15); a first conductor (30) comprising a conductive wire; and a second conductor (40) comprising a conductor plate. The first conductor (30) has a first body portion (31) extending along the mounting surface (15) inside the core. The second conductor (40) has a second body section (41) that extends along the mounting surface (15) inside the core and faces the first body section (31). In a direction in which the first main body section (31) and the second main body section (41) face each other, the first main body section (31) is located on the side of the core, and the first main body section (31) and the second main body section (41) are shifted toward the side of the core on which the first main body section (31) is located.

Description

Technical Field

[0001] The present disclosure relates to a coil arrangement that can be used, for example, as a coupled inductor. Background Art

[0002] For example, in a power circuit of a server, a coil device called a coupled inductor is sometimes used to improve the response speed of a voltage regulator or to reduce the number of components in a power circuit. As such a coil device, a coil device having a core, a first conductor, and a second conductor is disclosed in Patent Document 1. The first conductor and the second conductor are formed of a conductor plate obtained by bending a copper plate into a predetermined shape. The first conductor and the second conductor are opposite to each other at a predetermined interval inside the core and are magnetically coupled.

[0003] In recent years, as the miniaturization of coil devices progresses, there is a trend that the distance between conductors becomes narrower. For example, in the coil device of Patent Document 1, in the case of further miniaturization, the first conductor and the second conductor are brought closer, and the distance between the first conductor and the second conductor becomes narrower. Therefore, when the coil device is mounted on a mounting substrate, solder or the like is attached in a manner that straddles the first conductor and the second conductor, and a short circuit defect may occur between the first conductor and the second conductor.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2009-117676 Summary of the invention

[0007] Problems to be solved by the invention

[0008] The present disclosure has been made in view of such actual conditions, and an object of the present disclosure is to provide a coil device capable of preventing a short-circuit failure during mounting.

[0009] Technical solutions to solve problems

[0010] In order to achieve the above object, the present disclosure provides a coil device having:

[0011] a core having a mounting surface;

[0012] A first conductor, which is composed of a wire; and

[0013] A second conductor, which is formed by a conductor plate,

[0014] The first conductor has a first main body extending inside the core along the mounting surface,

[0015] The second conductor has a second main body portion extending along the mounting surface inside the core and opposite to the first main body portion.

[0016] In the direction in which the first body portion and the second body portion are opposite to each other, the first body portion is located at one side of the core, and the first body portion and the second body portion are offset to the side of the core where the first body portion is located.

[0017] In the coil device of the present disclosure, the first conductor is formed of a wire, and the second conductor is formed of a conductor plate. Therefore, for the first conductor, punching or bending of the conductor plate is not required. This makes it possible to facilitate the manufacture of the coil device and reduce costs.

[0018] In addition, in the direction in which the first body portion and the second body portion are relative to each other, the first body portion and the second body portion are offset to one side of the core where the first body portion is located. Therefore, a space corresponding to the offset amount of the first body portion and the second body portion is formed on the other side of the core. By utilizing this space, a part of the second conductor (for example, the mounting portion) is configured to be separated from the first conductor, thereby preventing the occurrence of a short circuit defect between the first conductor and the second conductor.

[0019] In addition, on the other side of the core, the volume of the core increases according to the offset amount of the first body portion and the second body portion. Therefore, the inductance characteristics and / or DC superposition characteristics of the coil device are improved.

[0020] Alternatively, in the direction in which the first main body and the second main body are relative to each other, the first main body and the second main body are located on one side closer to the core than the center of the core. In this case, a space for arranging a part of the second conductor (e.g., a mounting portion) is formed at least on the other side closer to the core than the center of the core. In this space, a part of the second conductor (e.g., a mounting portion) is arranged to be separated from the first conductor, thereby effectively preventing the occurrence of a short circuit between the first conductor and the second conductor.

[0021] The first conductor has a first mounting portion exposed from the core, and the second conductor has a second mounting portion exposed from the core, and the second mounting portion extends to the other side of the core in a manner separated from the first mounting portion. In this case, the second mounting portion is arranged at a position separated from the first mounting portion. Therefore, when the coil device is mounted on the mounting substrate, solder or the like is not easy to be attached in a manner spanning the first mounting portion and the second mounting portion. Thus, the occurrence of a short circuit defect can be effectively prevented between the first conductor and the second conductor.

[0022] Alternatively, the first mounting portion and the second mounting portion may be arranged on the inner side of the outer edge of the core when viewed from a direction perpendicular to the mounting surface. Such a structure is obtained, for example, by miniaturizing the first mounting portion and the second mounting portion, or by increasing the volume of the core. In the former case, the miniaturization of the coil device can be achieved. In the latter case, the inductance characteristics of the coil device can be improved.

[0023] The core has a recessed portion formed on a side surface of the core perpendicular to the mounting surface, and the first mounting portion and the second mounting portion are accommodated in the recessed portion. In this case, when viewed from a direction perpendicular to the mounting surface, the first mounting portion and the second mounting portion are not easily exposed from the outer edge of the core. Therefore, the miniaturization of the coil device can be achieved.

[0024] Alternatively, in the direction in which the first body portion and the second body portion are relative to each other, the first width of the first body portion and the second width of the second body portion are different. In this case, the magnetic coupling between the first body portion and the second body portion can be adjusted according to the difference between the first width and the second width. In addition, a large current can flow through the conductor having a larger first width and a larger second width.

[0025] The first width may be larger than the second width. In this case, a large current can flow through the first conductor.

[0026] Alternatively, the height position of the first main body from the mounting surface is different from the height position of the second main body from the mounting surface. In this case, the magnetic coupling between the first main body and the second main body can be adjusted according to the difference in the height position of the first main body from the mounting surface and the height position of the second main body from the mounting surface.

[0027] The first main body portion may be in contact with the second main body portion. In this case, the magnetic coupling between the first main body portion and the second main body portion can be improved.

[0028] The second conductor may include a plating layer formed on at least a portion of the second conductor. For example, by forming the plating layer at the end portion (mounting portion) in the extending direction of the second conductor, it is easy to connect the second conductor to the mounting substrate using solder or the like.

[0029] Alternatively, the first conductor may include an insulating coating formed on at least a portion of the first conductor. In this case, the first conductor can be insulated from the second conductor by the insulating coating. Therefore, a short circuit failure between the first conductor and the second conductor can be effectively prevented. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a perspective view of a coil device according to one embodiment of the present disclosure.

[0031] Figure 2 yes Figure 1 A perspective view of the first core is shown.

[0032] Figure 3 yes Figure 1 An exploded perspective view of the coil device shown.

[0033] Figure 4 yes Figure 1 A three-dimensional view of the first conductor and the second conductor shown.

[0034] Figure 5 It is along Figure 1 A cross-sectional view of the coil device taken along line VV is shown.

[0035] Figure 6 Is installed Figure 3 A top view of the first conductor and the first core of the second conductor is shown. DETAILED DESCRIPTION

[0036] Hereinafter, the embodiments of the present disclosure will be described with reference to the accompanying drawings. In addition, the contents of the drawings are only schematically and exemplarily shown for the purpose of understanding the present disclosure, and the appearance or dimensional ratio may be different from the actual object. In addition, the present disclosure is not limited to the following embodiments.

[0037] Figure 1 The coil device 1 shown functions as a coupled inductor and is provided in a power supply circuit of a server, for example. The coil device 1 includes a first core 10, a second core 20, a first conductor 30, and a second conductor 40. The core of the present embodiment is composed of two cores, the first core 10 and the second core 20, but may also be composed of one core, or three or more cores.

[0038] exist Figure 1 to Figure 6 In the figure, the X-axis is an axis along the axial direction of the first conductor 30 (first main body 31) or the second conductor 40 (second main body 41). The Y-axis is an axis along the relative direction of the first conductor 30 and the second conductor 40. The Z-axis is an axis perpendicular to the X-axis and the Y-axis. The X-axis, the Y-axis, and the Z-axis are perpendicular to each other. In the following, with respect to each axis in the X-axis, the Y-axis, and the Z-axis, the direction away from the center of the coil device 1 is set as the "outside", and the direction close to the center of the coil device 1 is set as the "inside". In addition, the positive direction side of the Z-axis is set as the "upper side", and the negative direction side of the Z-axis is set as the "lower side". However, the upper side in the Z-axis direction is not necessarily consistent with the upper side in the vertical direction. In addition, the lower side in the Z-axis direction is not necessarily consistent with the lower side in the vertical direction.

[0039] The width of the coil device 1 in the X-axis direction is not particularly limited, and is, for example, 3.0 to 20.0 mm. The width of the coil device 1 in the Y-axis direction is not particularly limited, and is, for example, 3.0 to 10.0 mm. The thickness of the coil device 1 in the Z-axis direction is not particularly limited, and is 3.0 to 10.0 mm.

[0040] like Figure 2 As shown, the first core 10 has a first side surface 11, a second side surface 12, a third side surface 13, a fourth side surface 14, a mounting surface 15, and a mounting opposite surface 16. The first side surface 11 and the second side surface 12 have the same shape and are located on opposite sides along the Y-axis. The shape of the first side surface 11 and the second side surface 12 is a rectangle, but can also be a square or other polygon. The third side surface 13 and the fourth side surface 14 have the same shape and are located on opposite sides along the X-axis. The mounting surface 15 and the mounting opposite surface 16 are located on opposite sides along the Z-axis. The first core 10 has a flat shape in which the width in the Z-axis direction is smaller than the width in the X-axis direction and the width in the Y-axis direction.

[0041] The first core 10 has a groove 17 formed on the mounting opposite surface 16. The groove 17 is located on one side (the second side surface 12 side) of the first core 10 in the Y-axis direction and extends along the X-axis. The groove 17 has a bottom surface 170 and inner walls 171 and 172. The bottom surface 170 is a flat surface parallel to the mounting surface 15. The inner walls 171 and 172 are surfaces perpendicular to the bottom surface 170. The inner wall 171 and the inner wall 172 are opposite to each other along the Y-axis.

[0042] In addition, in this embodiment, "parallel" is not limited to strictly parallel. In addition, "perpendicular" is not limited to strictly perpendicular.

[0043] The first core 10 has a recess 18a formed on the third side surface 13 and a recess 18b formed on the fourth side surface 14. The third side surface 13 and the fourth side surface 14 are both perpendicular to the mounting surface 15. The recess 18a is recessed inward from the third side surface 13 along the X-axis. The recess 18b is recessed inward from the fourth side surface 14 along the X-axis. The recesses 18a and 18b have a lateral bottom surface 180. The lateral bottom surface 180 is a flat surface and is perpendicular to the mounting surface 15. The groove 17 extends from the lateral bottom surface 180 of the recess 18a to the lateral bottom surface 180 of the recess 18b along the X-axis.

[0044] The first core 10 is formed of a composite material including a magnetic material and a resin. The first core 10 is formed, for example, by powder pressing, injection molding, or cutting. The magnetic material constituting the first core 10 is not particularly limited, and is, for example, ferrite (Ni-Zn ferrite, Mn-Zn ferrite, etc.) or a metal magnetic body. The resin constituting the first core 10 is not particularly limited, and is, for example, an epoxy resin or a phenol resin.

[0045] like Figure 3As shown, the second core 20 has a rectangular parallelepiped shape. In addition, the second core 20 has a flat shape in which the width in the Z-axis direction is smaller than the width in the X-axis direction and the width in the Y-axis direction. The second core 20 is formed, for example, by powder pressing, injection molding or cutting. The second core 20 has a contact surface 21 that contacts the mounting opposite surface 16 of the first core 10. The second core 20 (contact surface 21) is bonded to the first core 10 (mounting opposite surface 16) by, for example, an adhesive.

[0046] The material constituting the second core 20 may be the same as or different from the material constituting the first core 10. The relative magnetic permeability of the second core 20 may be the same as or different from the relative magnetic permeability of the first core 10.

[0047] The width of the second core 20 in the X-axis direction is not particularly limited, and is equal to the maximum width of the first core 10 in the X-axis direction. The width of the second core 20 in the Y-axis direction is not particularly limited, and is equal to the width of the first core 10 in the Y-axis direction. The thickness of the second core 20 in the Z-axis direction is not particularly limited, and is thinner than the thickness of the first core 10 in the Z-axis direction.

[0048] Figure 4 The first conductor 30 shown is made of a conductive wire (a rectangular wire in this embodiment). The first conductor 30 has flexibility (lower rigidity than the second conductor 40) and is configured to be deformable (bendable). The first conductor 30 is formed by bending the conductive wire into a Figure 4 The first conductor 30 is formed in the shape (C-shape) shown in FIG. 1 . The first conductor 30 is an insulating coated wire having a conductive core wire such as a rectangular wire covered with an insulating coating (insulating coating layer) 33. More specifically, the first conductor 30 is a well-known winding such as AIW (polyamide-imide copper wire), UEW (polyurethane copper wire), PEW (polyester copper wire), etc. There is no particular limitation on the material constituting the first conductor 30, and it is, for example, copper, copper alloy, silver or nickel. In addition, the first conductor 30 may not have the coating 33.

[0049] The first conductor 30 is a primary coil, and the second conductor 40 is a secondary coil. However, the first conductor 30 may be a secondary coil, and the second conductor 40 may be a primary coil. The first conductor 30 and the second conductor 40 constitute a coupled coil that is magnetically coupled to each other.

[0050] like Figure 4 As shown, the first conductor 30 has a first main body 31 and first mounting parts 32a, 32b. The first main body 31 is elongated along the X-axis and extends in a straight line. The cross-sectional shape of the first main body 31 is a rectangle, but it can also be a square, a trapezoid, other polygons, or other shapes. The first width W1 of the first conductor 30 in the Y-axis direction is not particularly limited and is 0.1 to 2.0 mm.

[0051] The first main body 31 has an upper surface, a bottom surface, and two side surfaces. These surfaces are flat surfaces that are perpendicular to each other. The upper surface and the bottom surface are located on opposite sides along the Z axis and are parallel to each other. The two side surfaces are located on opposite sides along the Y axis and are parallel to each other. The upper surface and the bottom surface are parallel to the XY plane ( Figure 3 The mounting surface 15) is parallel to the XY plane ( Figure 3 The mounting surface 15) is vertical.

[0052] At least one of the two side surfaces, the top surface, and the bottom surface of the first main body 31 may not be a flat surface, and may be, for example, an inclined surface, a concave-convex surface, a curved surface, or a bent surface. Figure 3 The mounting surface 15 may be perpendicular to the mounting surface 15, but may also be an inclined surface inclined at a predetermined angle (for example, greater than 30° and less than 90°) relative to the mounting surface 15.

[0053] The first mounting portion 32a is continuous with one axial end of the first main body portion 31, and the first mounting portion 32b is continuous with the other axial end of the first main body portion 31. Figure 4 In FIG. 1 , the boundary between the first main body 31 and the first mounting portion 32a and the boundary between the first main body 31 and the first mounting portion 32b are indicated by dot-dash lines. The shape of the first mounting portion 32a is the same as that of the first mounting portion 32b, but may be different.

[0054] The first mounting parts 32a and 32b are bent into an L-shape. The first mounting parts 32a and 32b are connected to the mounting substrate by solder or a conductive adhesive, etc. The first mounting parts 32a and 32b have a bent part 321 and a leg part 322, respectively.

[0055] The bent portion 321 is continuous with the first main body portion 31, and is bent in an L-shape (C-shape) between the first main body portion 31 and the leg portion 322. The leg portion 322 extends in a straight line along the Z axis. The leg portion 322 is orthogonal to the first main body portion 31. The cross-sectional shape of the leg portion 322 is a rectangle, but may also be a square, other polygons, or other shapes.

[0056] The coating 33 covers the first main body 31, the bent portion 321, and a portion of the leg 322. The coating 33 is peeled off from a portion of the leg 322 so that solder or a conductive adhesive can be easily attached. However, the coating 33 may cover the entire leg 322. The coating 33 covers the entire first main body 31, but may cover a portion of the first main body 31.

[0057] The second conductor 40 has a second main body 41 and second mounting portions 42a and 42b. The second main body 41 is elongated along the X-axis and extends in a straight line. The second main body 41 is arranged side by side with the first main body 31. The cross-sectional shape of the second main body 41 is a rectangle, but it can also be a square, a trapezoid, other polygons, or other shapes. The second width W2 of the second conductor 40 in the Y-axis direction is not particularly limited and is 0.1 to 2.0 mm.

[0058] The second conductor 40 is formed of a metal frame. The second conductor 40 is formed by, for example, machining (for example, punching, bending, cutting, stamping, sheet metal processing, casting or forging) a metal plate (conductor plate) or a metal sheet (conductor sheet) into a Figure 4 The second conductor 40 is formed in the shape shown. The second conductor 40 has higher rigidity than general conductive wires (round wires, rectangular wires, etc.). The rigidity of the second conductor 40 is higher than that of the first conductor 30. The material constituting the second conductor 40 is not particularly limited, and is, for example, copper, copper alloy, silver or nickel.

[0059] A plated film (plated layer) is formed on at least a portion of the second conductor 40. In the present embodiment, a plated film is formed on the entire second conductor 40, but a plated film may be formed only on a portion of the second conductor 40 (for example, the second mounting portions 42a and 42b). By forming a plated layer on the second mounting portions 42a and 42b, the solder wettability of the second mounting portions 42a and 42b is improved. Therefore, it is easy to connect the second conductor 40 to the mounting substrate by solder or a conductive adhesive. The plated film may be a single layer or a multilayer. The plated film is not particularly limited, and may be, for example, Cu-plated, Ni-plated, Sn-plated, Ni-Sn-plated, Cu-Ni-Sn-plated, Ni-Au-plated, or Au-plated.

[0060] The second main body 41 has an upper surface, a bottom surface, and two side surfaces. These surfaces are flat surfaces perpendicular to each other. The upper surface and the bottom surface are located on opposite sides along the Z axis and are parallel to each other. The two side surfaces are located on opposite sides along the Y axis and are parallel to each other. The upper surface and the bottom surface are parallel to the XY plane ( Figure 3 The mounting surface 15) is parallel to the XY plane ( Figure 3 The mounting surface 15) is vertical.

[0061] At least one of the two side surfaces, the top surface, and the bottom surface of the second main body 41 may not be a flat surface, and may be, for example, an inclined surface, a concave-convex surface, a curved surface, or a bent surface. Figure 3 The mounting surface 15 may be perpendicular to the mounting surface 15, but may also be an inclined surface inclined at a specified angle (for example, greater than 30° and less than 90°) relative to the mounting surface 15.

[0062] In the direction (Y-axis direction) in which the first body portion 31 and the second body portion 41 are opposite to each other, the first width W1 of the first body portion 31 is different from the second width W2 of the second body portion 41. Therefore, the magnetic coupling between the first body portion 31 and the second body portion 41 can be adjusted according to the difference between the first width W1 and the second width W2. In addition, a large current can flow through a conductor (in this embodiment, the first conductor 30) having a larger width of the first width W1 and the second width W2.

[0063] The first width W1 is greater than the second width W2. The ratio W1 / W2 of the first width W1 to the second width W2 is not particularly limited, and is 1<W1 / W2≤4, or 1<W1 / W2≤2, or 2≤W1 / W2≤3. In this case, the inductance characteristics and / or DC superposition characteristics of the coil device 1 are improved.

[0064] The second mounting portion 42a is continuous with one axial end of the second main body portion 41, and the second mounting portion 42b is continuous with the other axial end of the second main body portion 41. Figure 4 In the figure, the boundary between the second main body 41 and the second mounting portion 42a and the boundary between the second main body 41 and the second mounting portion 42b are indicated by a dashed line. The shape of the second mounting portion 42a is the same as that of the second mounting portion 42b, but may be different.

[0065] The second mounting parts 42a and 42b have a bent shape. The second mounting parts 42a and 42b are connected to the mounting substrate by solder or a conductive adhesive, etc. The second mounting parts 42a and 42b have a bent part 421, a leg part 422, and a middle part 423, respectively.

[0066] The bent portion 421 is continuous with the second main body portion 41, and is bent in an L-shape (C-shape) between the second main body portion 41 and the intermediate portion 423. The intermediate portion 423 is located between the bent portion 421 and the leg portion 422. The intermediate portion 423 is orthogonal to the bent portion 421 and the leg portion 422. The intermediate portion 423 extends linearly along the Y-axis in a manner separated from the leg portion 322 of the first conductor 30. The leg portion 422 extends linearly along the Z-axis. The cross-sectional shape of the leg portion 422 is a rectangle, but may also be a square, other polygons, or other shapes.

[0067] like Figure 3 As shown, the first body portion 31 and the second body portion 41 are arranged inside the groove portion 17. The first body portion 31 extends along the mounting surface 15 inside the groove portion 17. The second body portion 41 extends along the mounting surface 15 inside the groove portion 17 in parallel with the first body portion 31. The depth of the groove portion 17 is equal to or greater than the thickness of the first body portion 31 or the second body portion 41 in the Z-axis direction, so that the first body portion 31 and the second body portion 41 are not exposed from the groove portion 17. Figure 5As shown, the first main body portion 31 is bonded to the bottom surface 170 of the groove portion 17 by the adhesive 70. In addition, the second main body portion 41 is bonded to the bottom surface 170 by the adhesive 70. However, the upper surface of the first main body portion 31 may also be bonded to the abutting surface 21 of the second core 20 by the adhesive 70. In addition, the upper surface of the second main body portion 41 may also be bonded to the abutting surface 21 of the second core 20 by the adhesive 70.

[0068] The first main body portion 31 and the second main body portion 41 are opposite to each other along the Y axis. In addition, the side surface of the first main body portion 31 (the side surface opposite to the second main body portion 41) is in contact with the side surface of the second main body portion 41 (the side surface opposite to the first main body portion 31). Therefore, the magnetic coupling between the first main body portion 31 and the second main body portion 41 can be improved. Since the first main body portion 31 has a coating (insulating coating layer) 33, the first main body portion 31 can be insulated from the second main body portion 41 by the coating 33. Thus, a short circuit failure between the first main body portion 31 and the second main body portion 41 can be prevented.

[0069] A gap may be formed between the first main body portion 31 and the second main body portion 41. In this case, the magnetic coupling between the first main body portion 31 and the second main body portion 41 can be adjusted according to the size of the gap. The gap may also be an air gap. Alternatively, the interior of the gap may be filled with an adhesive (e.g., a bead-containing adhesive). Alternatively, a portion of the first core 10 or the second core 20 may be disposed in the gap. Alternatively, a partition member (spacer) or a membrane (film) formed of a non-conductive member such as a resin may be disposed in the gap.

[0070] A gap 61 is formed between the first body portion 31 and the inner wall 171 of the groove portion 17, but the first body portion 31 may abut against the inner wall 171. Alternatively, the first body portion 31 and the inner wall 171 may be bonded by an adhesive.

[0071] In addition, a gap 62 is formed between the second body portion 41 and the inner wall 172 of the groove portion 17, but the second body portion 41 may abut against the inner wall 172. Alternatively, the second body portion 41 and the inner wall 172 may be bonded by an adhesive.

[0072] The first main body portion 31 and the second main body portion 41 are contained in a space defined by the groove portion 17 in a manner of being clamped from above and below by the first core 10 and the second core 20. The upper surface of the first main body portion 31 is in contact with the abutting surface 21 of the second core 20, but a gap may be formed therebetween. In addition, the upper surface of the second main body portion 41 is in contact with the abutting surface 21 of the second core 20, but a gap may be formed therebetween.

[0073] The height position of the first body portion 31 (including the coating 33) from the mounting surface 15 is equal to the height position of the second body portion 41 from the mounting surface 15. Therefore, the upper surface of the first body portion 31 (including the coating 33) is flush with the upper surface of the second body portion 41, and the bottom surface of the first body portion 31 is flush with the bottom surface of the second body portion 41.

[0074] However, the height position of the first body portion 31 from the mounting surface 15 may be different from the height position of the second body portion 41 from the mounting surface 15. The height position of the first body portion 31 from the mounting surface 15 may be higher than the height position of the second body portion 41 from the mounting surface 15. Alternatively, the height position of the second body portion 41 from the mounting surface 15 may be higher than the height position of the first body portion 31 from the mounting surface 15. In either case, the magnetic coupling between the first body portion 31 and the second body portion 41 can be adjusted according to the difference in the height position of the first body portion 31 from the mounting surface 15 and the height position of the second body portion 41 from the mounting surface 15.

[0075] When viewed from the X-axis direction, the foot 322 of the first mounting portion 32b is located on the inner side of the Y-axis direction than the second side surface 12 of the first core 10. Although detailed illustrations are omitted, the same is true for the foot 322 of the first mounting portion 32a. In addition, when viewed from the X-axis direction, the foot 422 of the second mounting portion 42b is located on the inner side of the Y-axis direction than the first side surface 11 of the first core 10. Although detailed illustrations are omitted, the same is true for the foot 422 of the second mounting portion 42a.

[0076] The lower portion of the leg 322 protrudes below the mounting surface 15 of the first core 10. The lower portion of the leg 422 protrudes below the mounting surface 15 of the first core 10. Therefore, the mounting surface 15 is located above the bottom surfaces of the legs 322 and 422.

[0077] like Figure 1 As shown, the first mounting portions 32a and 32b are exposed from the first core 10 and the second core 20. In addition, the second mounting portions 42a and 42b are exposed from the first core 10 and the second core 20. In more detail, Figure 4 The bent portion 321 and the foot portion 322 are shown in Figure 1 The recessed portion 18a or 18b shown is exposed from the first core 10 and the second core 20. Figure 4 The bent portion 421, the foot portion 422 and the middle portion 423 are shown in Figure 1 The recessed portion 18 a or 18 b shown is exposed from the first core 10 and the second core 20 .

[0078] The second mounting portion 42a (middle portion 423) extends toward the first side surface 11 of the first core 10 in a manner separated from the first mounting portion 32a. Although detailed illustrations are omitted, the second mounting portion 42b (middle portion 423) extends toward the first side surface 11 of the first core 10 in a manner separated from the first mounting portion 32b. Therefore, the second mounting portion 42a is arranged at a position separated from the first mounting portion 32a along the Y-axis direction. As a result, when the coil device 1 is mounted on the mounting substrate, solder or conductive adhesive is not easy to adhere in a manner spanning the first mounting portion 32a and the second mounting portion 42a. Thus, it is possible to prevent the occurrence of a short circuit defect between the first conductor 30 and the second conductor 40.

[0079] The first mounting portions 32a and 32b are arranged on both sides of the first core 10 in the X-axis direction so as to sandwich the first core 10 from both sides in the X-axis direction. Figure 6 As shown, the second mounting portions 42 a and 42 b are arranged on both sides of the first core 10 in the X-axis direction so as to sandwich the first core 10 from both sides in the X-axis direction.

[0080] When viewed from a direction perpendicular to the mounting surface 15 (Z-axis direction), the first mounting portion 32a and the second mounting portion 42a are arranged on the inner side of the outer edge of the second core 20. In addition, when viewed from a direction perpendicular to the mounting surface 15 (Z-axis direction), the first mounting portion 32b and the second mounting portion 42b are arranged on the inner side of the outer edge of the second core 20. By miniaturizing the first mounting portion 32a and the second mounting portion 42a in such a manner that the first mounting portion 32a and the second mounting portion 42a are not exposed to the outside from the outer edge of the second core 20, the miniaturization of the coil device 1 can be achieved. In addition, by increasing the volume of the second core 20 in such a manner that the first mounting portion 32a and the second mounting portion 42a are not exposed to the outside from the outer edge of the second core 20, the inductance characteristics of the coil device 1 can be improved.

[0081] The first mounting portions 32a and 32b are formed by Figure 6 The second core 20 shown by the double-dashed line in FIG. is covered from above. Therefore, when viewed from above, the first mounting portions 32a and 32b are hidden by the second core 20. In addition, the second mounting portions 42a and 42b are hidden by the second core 20. Figure 6 The second core 20 shown by the double-dashed line in FIG. 2 covers from above. Therefore, when viewed from above, the second mounting portions 42a and 42b are hidden by the second core 20.

[0082] The first mounting portion 32a and the second mounting portion 42a are accommodated in the recessed portion 18a. In addition, the first mounting portion 32b and the second mounting portion 42b are accommodated in the recessed portion 18b. Therefore, the first mounting portion 32a, the first mounting portion 32b, the second mounting portion 42a, and the second mounting portion 42b are not easily exposed from the outer edge of the second core 20, and the coil device 1 can be miniaturized.

[0083] like Figure 6 As shown, in the direction (Y-axis direction) in which the first main body portion 31 and the second main body portion 41 are relative to each other, the first main body portion 31 and the second main body portion 41 are integrated and offset to one side of the first core 10 where the first main body portion 31 is located (the second side surface 12 side). The direction in which the first main body portion 31 and the second main body portion 41 are offset is the side on which the first main body portion 31 is arranged, in other words, the side opposite to the side on which the second main body portion 41 is arranged. In the present embodiment, both the first main body portion 31 and the second main body portion 41 are offset to one side of the first core 10. In addition, both the first main body portion 31 and the second main body portion 41 are offset to one side of the second core 20 (the negative direction side of the Y-axis). In addition, the first mounting portions 32a and 32b are offset to one side of the first core 10 and the second core 20.

[0084] In the direction (Y-axis direction) in which the first main body portion 31 and the second main body portion 41 are relative to each other, the first main body portion 31 and the second main body portion 41 are located on the side (the second side 12 side) closer to the first core 10 than the center C1 of the first core 10. In the present embodiment, in the Y-axis direction, the entire first main body portion 31 is located on the side of the first core 10 closer to the center C1 of the first core 10. In addition, in the Y-axis direction, the entire second main body portion 41 is located on the side of the first core 10 closer to the center C1 of the first core 10. However, in the Y-axis direction, a portion of the second main body portion 41 may also be located on the other side (the first side 11 side) closer to the first core 10 than the center C1 of the first core 10.

[0085] In addition, the position of the center C1 of the first core 10 is equal to the position of the center of the second core 20. Here, "equal" does not only mean that their positions are strictly consistent, but also includes the concept of "equal" in which their positions are offset by less than a few percent (for example, 5%) in the Y-axis direction and / or the X-axis direction.

[0086] The first body portion 31 and the second body portion 41 constitute a magnetic coupling portion 50 that is magnetically coupled to each other. The magnetic coupling portion 50 is a virtual structure that regards the first body portion 31 and the second body portion 41 as one structure. The magnetic coupling between the first body portion 31 and the second body portion 41 can be adjusted according to the distance between the first body portion 31 and the second body portion 41 along the Y axis.

[0087] The center axis C2 of the magnetic coupling portion 50 is separated from the center C1 of the first core 10 by a distance D in the Y-axis direction. The ratio D / W3 of the distance D between the center axis C2 of the magnetic coupling portion 50 and the center C1 of the first core 10 and the width W3 of the first core 10 or the second core 20 in the Y-axis direction is not particularly limited, and is 1 / 10≤D / W3≤1 / 3, or 1 / 8≤D / W3≤1 / 4.

[0088] As described above, in the coil device 1 of the present embodiment, the first conductor 30 is formed of a wire, and the second conductor 40 is formed of a conductor plate. Therefore, punching or bending of the conductor plate is not required for the first conductor 30. Thus, the coil device 1 can be manufactured more easily and at a lower cost.

[0089] In addition, in the direction (Y-axis direction) in which the first main body portion 31 and the second main body portion 41 are relative to each other, the first main body portion 31 and the second main body portion 41 (magnetic coupling portion 50) are offset toward the second side surface 12 of the first core 10. Therefore, a space corresponding to the offset amount of the first main body portion 31 and the second main body portion 41 is formed on the first side surface 11 of the first core 10. By utilizing this space, a portion of the second conductor 40 (the second mounting portions 42a and 42b in this embodiment) is configured to be separated from the first conductor 30. Thus, a short circuit failure can be prevented from occurring between the first conductor 30 and the second conductor 40 (particularly the second mounting portions 42a and 42b).

[0090] Furthermore, the volume of the first core 10 increases on the first side surface 11 of the first core 10 due to the offset of the first body portion 31 and the second body portion 41 (magnetic coupling portion 50 ). Therefore, the inductance characteristics and / or DC superposition characteristics of the coil device 1 are improved.

[0091] In addition, in the direction in which the first main body portion 31 and the second main body portion 41 are relative to each other (the Y-axis direction), the first main body portion 31 and the second main body portion 41 (the magnetic coupling portion 50) are located closer to the second side surface 12 of the first core 10 than the center C1 of the first core 10. Therefore, a space for arranging a part of the second conductor 40 (the second mounting portions 42a and 42b in this embodiment) is formed closer to the first side surface 11 than the center C1 of the first core 10. In this space, a part of the second conductor 40 (the second mounting portions 42a and 42b in this embodiment) is arranged to be separated from the first conductor 30. Thus, the occurrence of a short circuit failure can be effectively prevented between the first conductor 30 and the second conductor 40 (particularly the second mounting portions 42a and 42b).

[0092] In addition, if Figure 4 As shown in FIG. 1 , the second width W2 of the second body portion 41 in the Y-axis direction is narrower than the first width W1 of the first body portion 31 in the Y-axis direction. Therefore, compared with the case where the first width W1 and the second width W2 are equal, Figure 6 The second main body 41 shown has more configuration space for the first core 10 (space corresponding to the difference between the first width W1 and the second width W2). As a result, the volume of the first core 10 increases around the second main body 41, and the inductance characteristics and / or DC superposition characteristics of the coil device 1 are improved.

[0093] Next, a method for manufacturing the coil device 1 will be described. First, prepare Figure 3 The first core 10, the second core 20, the first conductor 30, and the second conductor 40 are shown. Figure 2 The bottom surface 170 of the groove portion 17 shown is bonded by an adhesive. Figure 3 The bottom surface of the first main body 31 is bonded to the bottom surface of the second main body 41. Figure 6 As shown in FIG. 1 , the first main body 31 and the second main body 41 are brought into close contact with each other. In addition, the first mounting portions 32a and 32b are arranged inside the recess 18a, and the second mounting portions 42a and 42b are arranged inside the recess 18b. Next, the adhesive is used to bond the first main body 31 and the second main body 41 together. Figure 3 The abutment surface 21 of the second core 20 shown is bonded to the mounting opposite surface 16 of the first core 10. As described above, it is possible to manufacture Figure 1 The coil arrangement 1 is shown.

[0094] In addition, the present disclosure is not limited to the above-mentioned embodiment, and various changes can be made within the scope of the present disclosure.

[0095] For example, Figure 6 As shown, in the above embodiment, the second body portion 41 extends in a straight line along the X-axis, but may be bent or curved. For example, the second body portion 41 may be bent or curved in a manner separated from the first body portion 31. In this case, a gap is formed between the first body portion 31 and the second body portion 41, and the magnetic coupling between the first body portion 31 and the second body portion 41 can be reduced.

[0096] In the above-mentioned embodiment, the application example of the coupled inductor of the present disclosure is described, but the present disclosure can also be applied to other electronic components.

[0097] like Figure 3 As shown, the core of the above embodiment is composed of two cores, the first core 10 and the second core 20, but it can also be composed of a single core. Such a core is formed, for example, by the following steps: (1) placing the first conductor 30 and the second conductor 40 in a mold; (2) filling the mold with a core material constituting the core; (3) compressing and curing the core material.

[0098] like Figure 3 As shown, in the above embodiment, the groove 17 for accommodating the first body 31 and the second body 41 is formed in the first core 10. However, the groove for accommodating the first body 31 and the second body 41 may also be formed in the second core 20.

[0099] Description of Reference Numerals

[0100] 1 ... coil device; 10 ... first core; 11 ... first side surface; 12 ... second side surface; 13 ... third side surface; 14 ... fourth side surface; 15 ... mounting surface; 16 ... mounting opposite surface; 17 ... groove portion; 170 ... bottom surface; 171, 172 ... inner wall; 18a, 18b ... recessed portion; 180 ... lateral bottom surface; 20 ... second core; 21 ... contact surface; 30 ... first conductor; 31 ... first main body portion; 32a, 32b ... first mounting portion; 321 ... bent portion; 322 ... leg portion; 33 ... coating; 40 ... second conductor; 41 ... second main body portion; 42a, 42b ... second mounting portion; 421 ... bent portion; 422 ... leg portion; 423 ... middle portion; 50 ... magnetic coupling portion; 61, 62 ... gap; 70 ... adhesive

Claims

1. A coil device, wherein: have: a core having a mounting surface; A first conductor, which is composed of a wire; as well as A second conductor, which is formed by a conductor plate, The first conductor has a first main body extending inside the core along the mounting surface, The second conductor has a second main body portion extending along the mounting surface inside the core and opposite to the first main body portion. In the direction in which the first body portion and the second body portion are opposite to each other, the first body portion is located at one side of the core, and the first body portion and the second body portion are offset to the side of the core where the first body portion is located.

2. The coil device according to claim 1, wherein: In the direction in which the first body portion and the second body portion oppose each other, the first body portion and the second body portion are located on one side of the core relative to the center of the core.

3. The coil device according to claim 1 or 2, wherein: The first conductor has a first mounting portion exposed from the core, The second conductor has a second mounting portion exposed from the core, The second mounting portion extends toward the other side of the core in a manner separated from the first mounting portion.

4. The coil device according to claim 3, wherein: The first mounting portion and the second mounting portion are arranged inside the outer edge of the core when viewed from a direction perpendicular to the mounting surface.

5. The coil device according to claim 4, wherein: The core has a recessed portion formed on a side surface of the core perpendicular to the mounting surface, The first mounting portion and the second mounting portion are accommodated in the recessed portion.

6. The coil device according to claim 1 or 2, wherein: In a direction in which the first body portion and the second body portion are opposite to each other, a first width of the first body portion is different from a second width of the second body portion.

7. The coil device according to claim 6, wherein: The first width is greater than the second width.

8. The coil device according to claim 1 or 2, wherein: A height position of the first main body portion from the mounting surface is different from a height position of the second main body portion from the mounting surface.

9. The coil device according to claim 1 or 2, wherein: The first main body portion abuts against the second main body portion.

10. The coil device according to claim 1 or 2, wherein: The second conductor has a plating layer formed on at least a portion of the second conductor.

11. The coil device according to claim 1 or 2, wherein: The first conductor has an insulating coating formed on at least a portion of the first conductor.

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