Coil device

Abstract

The present invention provides a coil device with high reliability. An inductor (1) has an air-core coil (2) and terminals (4a, 4b) connected to the ends of the air-core coil (2). Positioning parts (43, 44) for limiting the position of the air-core coil (3) are formed on the terminals (4a, 4b).

Description

Technical Field

[0001] The present invention relates to a coil device used as, for example, an inductor or the like. Background Art

[0002] As coil devices used as inductors, for example, coil devices described in Patent Documents 1 and 2 are known. The coil device described in Patent Document 1 includes a magnetic core, a coil wound around a columnar portion (winding core portion) of the magnetic core, and a terminal connected to the end of the coil. By forming a protrusion on a part of the terminal and making the protrusion abut against the outer side surface of the lower flange portion, the terminal can be prevented from being misaligned with respect to the magnetic core.

[0003] In addition, the coil device described in Patent Document 2 has a coil, a terminal connected to the end of the coil, and a magnetic core that covers the connection portion of the terminal together with the coil. In the coil device described in Patent Document 2, the connection portion is arranged inside the magnetic core, so the connection portion can be protected from external factors such as external force.

[0004] However, in the coil device described in Patent Document 1, when manufacturing the coil device, the coil and the terminal are sometimes combined with the magnetic core in a state where the end of the coil is connected to the terminal. In this case, if the coil is misaligned with respect to the terminal, when the terminal is arranged at a predetermined position of the magnetic core, a defect such as the columnar portion of the magnetic core contacting the inner peripheral surface of the coil occurs, resulting in deviations in the inductance characteristics of each product, and the reliability of the product may be reduced.

[0005] In addition, in the coil device described in Patent Document 2, when a coil formed by flat-winding a flat wire is used, the end of the coil needs to be twisted in order to connect the end of the coil to a terminal. However, in this case, the inductance characteristics vary among products, and the reliability of the coil device may be reduced.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Laid-Open No. 10-22137

[0009] Patent Document 2: Japanese Patent Application Publication No. 2007-165779 Summary of the invention

[0010] Problems to be solved by the invention

[0011] The present invention has been made in view of such actual conditions, and an object of the present invention is to provide a coil device with high reliability.

[0012] Technical solutions to the problem

[0013] In order to achieve the above-mentioned object, a first aspect of the present invention provides a coil device having:

[0014] Air core coil; and

[0015] The terminals connected to the ends of the air-core coils,

[0016] The terminal is formed with a protrusion that restricts the position of the air-core coil.

[0017] In the coil device of the present invention, a protrusion that limits the position of the air-core coil is formed on the terminal. Therefore, when the end of the coil is connected to the terminal, the position of the coil relative to the terminal is limited by the protrusion, which can prevent the coil from being misaligned with respect to the terminal. Moreover, in this state, when the terminal and the coil are arranged at a specified position of the magnetic core together, the coil is smoothly inserted into the columnar portion (winding core portion) of the magnetic core, which can prevent the columnar portion of the magnetic core from contacting the inner circumferential surface of the coil. Therefore, according to the present invention, the unevenness of the inductance characteristics of each product caused by this undesirable situation can be prevented, thereby realizing a coil device with high reliability. In addition, by preventing such an undesirable situation, it is possible to facilitate the manufacture of the coil device.

[0018] Preferably, the protrusion is arranged near the outer periphery of the air-core coil. By adopting such a structure, the deviation width of the position of the coil relative to the terminal can be reduced, and the displacement of the coil relative to the terminal can be effectively prevented.

[0019] Preferably, the protrusion does not abut against the outer peripheral surface of the coil. By setting such a structure, when, for example, an insulating film is formed on the outer surface of the coil, damage to the insulating film due to friction with the protrusion can be prevented, and a short circuit between the terminal and the coil (the outer peripheral surface of the coil) is not likely to occur.

[0020] Preferably, there is a magnetic core including a columnar portion inserted into the air-core coil. With such a structure, the effective magnetic permeability of the magnetic core in the area inside the coil can be sufficiently ensured, and the inductance characteristics of the coil device can be improved.

[0021] Preferably, the distance between the outer peripheral surface of the columnar portion and the inner peripheral surface of the coil is larger than the distance between the protrusion and the outer peripheral surface of the coil. In this case, a first gap is formed between the outer peripheral surface of the columnar portion and the inner peripheral surface of the coil, and a second gap is formed between the protrusion and the outer peripheral surface of the coil. Assuming that the coil is configured in a position offset relative to the terminal within the range of the second gap, a gap corresponding to the width of the difference between the first gap and the second gap is formed between the outer peripheral surface of the columnar portion and the inner peripheral surface of the coil. Therefore, even if the coil is configured in a position offset relative to the terminal within the range of the second gap, a gap is still formed between the outer peripheral surface of the columnar portion and the inner peripheral surface of the coil, and there will be no adverse conditions such as the columnar portion contacting the inner peripheral surface of the coil, and the coil can be inserted into the columnar portion.

[0022] Preferably, there is a pair of the terminals, and the protrusion of one terminal and the protrusion of the other terminal are arranged between the pair of ends of the hollow coil. By setting such a structure, the winding part and the position of each end of the coil can be restricted by the protrusion, which can effectively prevent the coil from being misaligned with respect to the terminal.

[0023] Preferably, there is a pair of the terminals, and the distance between the protrusion formed on one end of one of the terminals and the protrusion formed on one end of the other terminal is smaller than the outer diameter of the coil. By setting such a structure, it is possible to prevent the coil from being misaligned toward one end of the terminal and the coil from being misaligned in a direction perpendicular to one end of the terminal.

[0024] Preferably, the protrusion functions as a connection portion of the terminal. With such a structure, the end of the coil can be connected to the terminal (protrusion), and the protrusion can prevent the coil from being misaligned with respect to the terminal.

[0025] In order to achieve the above object, a second aspect of the present invention provides a coil device having:

[0026] A coil formed by winding a flat wire flat;

[0027] a terminal having a holding surface at a connection portion for holding an end of the coil; and

[0028] a magnetic core covering the wiring portion and the coil,

[0029] The holding surface extends substantially parallel to a winding axis of the coil.

[0030] In the coil device of the present invention, the holding surface of the terminal extends parallel to the winding axis of the coil. In the coil formed by flat-winding a flat wire, the surface of the long side of the end portion also extends parallel to the winding axis. Therefore, when the end portion is led out from the winding portion of the coil, even if the end portion is not twisted, the surface of the long side can be aligned with the direction of the holding surface of the wiring portion. Therefore, the holding surface can be used to hold the end portion of the coil without twisting it, and a coil device with high reliability can be realized that prevents unevenness in the inductance characteristics of the coil device.

[0031] Preferably, the holding surface is opposite to the side surface of the magnetic core. With such a structure, when the connection portion (holding surface) is subjected to laser welding, for example, it is easy to irradiate the coil device with laser light from the side, thereby facilitating manufacturing.

[0032] Preferably, the end of the coil is bent into a substantially L-shape. By setting such a structure, the surface of the long side of the end of the coil can be easily made to face the side of the magnetic core. Therefore, when the end of the coil is held by the holding surface of the wiring portion, the holding surface is arranged opposite to the side of the magnetic core, and it is easy to irradiate the laser from the side of the coil device.

[0033] Preferably, the connection portion is arranged outside an imaginary line parallel to the side of the magnetic core and in contact with the outer periphery of the coil. By setting such a structure, the connection portion can be arranged at a position sufficiently separated from the coil. Therefore, when laser welding is performed on the connection portion, it is possible to prevent a portion of the laser from being irradiated on the winding portion of the coil, thereby reducing damage to the winding portion caused by the coil. In addition, it is possible to prevent a portion of the laser from being irradiated on the magnetic core, thereby also reducing damage to the magnetic core.

[0034] Preferably, when viewed from a direction perpendicular to the side surface of the magnetic core, the connection portion and the remaining portion of the terminal other than the connection portion are arranged at offset positions. By setting such a structure, the connection portion can be arranged at a position sufficiently separated from the coil in a direction parallel to the side surface of the magnetic core, and the above-mentioned effect can be obtained when laser welding is applied to the connection portion.

[0035] Preferably, the terminal has a fixing portion disposed inside the magnetic core, and an opening is formed in the fixing portion. With such a structure, the material forming the magnetic core can enter the inside of the opening, and the terminal can be fixed to the magnetic core with sufficient fixing strength.

[0036] Preferably, the magnetic core includes magnetic particles and a resin binder. With such a structure, a coil device having good inductance characteristics can be realized.

[0037] Preferably, there is a pair of the terminals, and the holding surface of one terminal and the holding surface of the other terminal face the same direction. With such a structure, when laser welding is performed on each connection portion (each holding surface) of each terminal, for example, it is easy to irradiate each connection portion (each holding surface) with a laser, which can facilitate manufacturing.

[0038] Preferably, there is a pair of terminals, and the connection portion of one terminal and the connection portion of the other terminal are arranged on a diagonal line with the coil sandwiched therebetween. By setting such a structure, either end of the coil can be held by the terminal arranged opposite to the side of the magnetic core without being bent into a substantially L-shaped shape and being led out straight. Therefore, it is easy to irradiate the terminal with laser from the side of the coil device. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a perspective view of the coil device according to the first embodiment of the present invention.

[0040] Figure 2 yes Figure 1 A three-dimensional view of the first magnetic core shown.

[0041] Figure 3 yes Figure 1 A perspective view of the coil is shown.

[0042] Figure 4 yes Figure 1 A perspective view of the terminal is shown.

[0043] Figure 5A Observe from different angles Figure 1 A perspective view of the coil arrangement shown.

[0044] Figure 5B Observe from different angles Figure 5A A perspective view of the coil device shown.

[0045] Fig. 6A Yes means Figure 1 FIG. 1 is a diagram showing a method for manufacturing a coil device.

[0046] Figure 6B Yes means Fig. 6A Figure 1 shows the subsequent process steps.

[0047] Figure 6C Yes means Figure 6B Figure 1 shows the subsequent process steps.

[0048] Fig.6D Yes means Figure 6C Figure 1 shows the subsequent process steps.

[0049] Fig. 6E Yes means Fig.6DFigure 1 shows the subsequent process steps.

[0050] Figure 7 It is a perspective view of a coil device according to a second embodiment of the present invention.

[0051] Figure 8 yes Figure 7 A three-dimensional view of the first magnetic core shown.

[0052] Fig. 9 yes Figure 7 A perspective view of the coil is shown.

[0053] Fig.10 yes Figure 7 A perspective view of the terminal is shown.

[0054] Fig.11 Observe from different angles Figure 7 A perspective view of the coil device shown.

[0055] Fig. 12A Yes means Figure 7 FIG. 1 is a diagram showing a method for manufacturing a coil device.

[0056] Fig. 12B Yes means Fig. 12A Figure 1 shows the subsequent process steps.

[0057] Fig. 12C Yes means Fig. 12B Figure 1 shows the subsequent process steps.

[0058] Fig.12D Yes means Fig. 12C Figure 1 shows the subsequent process steps.

[0059] Fig.12E Yes means Fig.12D Figure 1 shows the subsequent process steps.

[0060] Fig.13 It is a perspective view of a coil device according to a third embodiment of the present invention. DETAILED DESCRIPTION

[0061] Hereinafter, the present invention will be described based on the embodiments shown in the drawings.

[0062] like Figure 1 As shown, the inductor 1 according to one embodiment of the present invention is formed in a substantially rectangular parallelepiped shape and has a coil 2, terminals 4a, 4b, a first magnetic core 5, and a second magnetic core 6. The inductor 1 has a shape in which the first magnetic core 5 and the second magnetic core 6 are combined in the Z-axis direction. The upper surface of the inductor 1 is formed on the first magnetic core 5 side, and the bottom surface (mounting surface) of the inductor 1 is formed on the second magnetic core 6 side. In addition, in order to facilitate understanding of the internal structure of the inductor 1, the second magnetic core 6 is represented by an imaginary line. In addition, in Figure 2 to Figure 6DIn the figure, for easy understanding, the above-mentioned structures are illustrated in a state of being reversed upside down.

[0063] The size of the inductor 1 is not particularly limited, but the width in the X-axis direction is preferably 2 to 20 mm, the width in the Y-axis direction is preferably 2 to 20 mm, and the width in the Z-axis direction is preferably 1 to 10 mm.

[0064] like Figure 2 As shown in FIG. 1 , the first magnetic core 5 has a base 50 and a columnar portion 53 formed on a surface (upper surface) of the base 50. Figure 1 As shown, when the inductor 1 is arranged with the mounting surface facing downward, the upper surface of the base 50 faces downward of the inductor 1 .

[0065] The first magnetic core 5 is made of a synthetic resin in which ferrite particles or metal magnetic particles are dispersed. However, the material constituting the first magnetic core 5 is not limited thereto, and may also be made of a synthetic resin that does not contain these particles. Examples of ferrite particles include Ni-Zn ferrites, Mn-Zn ferrites, and the like. Examples of metal magnetic particles are not particularly limited, and examples include Fe-Ni alloy powder, Fe-Si alloy powder, Fe-Si-Cr alloy powder, Fe-Co alloy powder, Fe-Si-Al alloy powder, amorphous iron, and the like.

[0066] The synthetic resin contained in the first magnetic core 5 is not particularly limited, and preferred examples thereof include epoxy resin, phenol resin, polyester resin, polyurethane resin, polyimide resin, and silicone resin.

[0067] The base 50 is formed in a substantially rectangular parallelepiped shape (substantially flat shape), and on its surface (upper surface) are formed first to fourth recesses 51a to 51d, first to fourth protrusions 52a to 52d, and a protrusion 54. The recesses 51a to 51d are formed at the four corners of the base 50, respectively, and have a substantially rectangular shape when viewed from the Z-axis direction.

[0068] The recesses 51a to 51d have a predetermined depth. Figure 1 The thickness (plate thickness) of the terminals 4a and 4b shown in FIG. 5 is substantially equal. That is, the depth of the recesses 51a to 51d is relatively shallow, and the upper surface of the base 50 is substantially flat. Figure 1 As shown, when the first core 5 and the second core 6 are combined, the first core 5 and the second core 6 can be joined on substantially the same plane.

[0069] like Figure 2As shown, the convex portions 52a to 52d have a surface shape consisting of a flat surface, and extend radially outward from the approximate center of the base 50 (a position slightly offset from the center of the base 50). The first convex portion 52a is formed between the first concave portion 51a and the fourth concave portion 51d, the second convex portion 52b is formed between the first concave portion 51a and the second concave portion 51b, the third convex portion 52c is formed between the second concave portion 51b and the third concave portion 51c, and the fourth convex portion 52d is formed between the third concave portion 51c and the fourth concave portion 51d.

[0070] A protrusion 54 is formed at the end of the third convex portion 52c in the Y-axis direction. The protrusion 54 protrudes from the upper surface of the third convex portion 52c in the Z-axis direction by a predetermined height. The width of the protrusion 54 in the X-axis direction is substantially equal to the width of the third convex portion 52c in the X-axis direction. When viewed from the Z-axis direction, the protrusion 54 has a substantially rectangular shape, and a tapered surface is formed on its upper surface.

[0071] As described later, the terminal 4a is arranged in the first recess 51a and the second recess 51b so as to straddle the second protrusion 52b (see Figure 5A In the third recess 51c and the fourth recess 51d, the terminal 4b is arranged so as to straddle the fourth protrusion 52d (see Figure 5A ). The protrusions 52a to 52d protrude in the Z-axis direction relative to the recesses 51a to 51d by the thickness of the terminals 4a and 4b, so that when the terminals 4a and 4b are arranged in the recesses 51a to 51d as described above, the upper surfaces of the protrusions 52a to 52d and the upper surfaces of the terminals 4a and 4b (the first carrier portion 41 and the second carrier portion 42) become substantially flush with each other.

[0072] The columnar portion 53 is integrally formed at the substantially central portion of the base 50 and extends in the Z-axis direction. The columnar portion 53 is formed slightly offset from the central portion of the base 50 toward the outside (to the negative direction of the Y-axis direction). Figure 1 The coil (air-core coil) 2 shown is inserted or wound. Therefore, the diameter of the columnar portion 53 is smaller than the inner diameter of the coil 2. The columnar portion 53 is formed in a cylindrical shape, and its height is higher than the height of the coil 2 (refer to Figure 5A ). By providing the columnar portion 53 on the first magnetic core 5, the effective magnetic permeability of the first magnetic core 5 in the region inside the coil 2 can be sufficiently ensured, and the inductance characteristics of the inductor 1 can be improved.

[0073] like Figure 3 As shown, the coil 2 is composed of an air-core coil, and is formed by vertically winding a conductor 3 composed of a flat wire. Although the coil 2 is α-wound, its winding method is not limited to this. The surface on the short side of the conductor 3 (the surface on the edge side) constitutes the inner peripheral surface or the outer peripheral surface of the coil 2, and the surface on the long side of the conductor 3 (the surface in the width direction) faces the Z-axis direction.

[0074] The material constituting the lead wire 3 includes, for example, good conductors of metals such as copper and copper alloys, silver, and nickel, but is not particularly limited as long as it is a conductive material. An insulating coating is applied to the surface of the lead wire 3. The resin constituting the insulating coating is not particularly limited, and for example, epoxy-modified acrylic resin can be used.

[0075] One end of the wire 3 (wire end 3a) constitutes one end of the coil 2, and the other end of the wire 3 (wire end 3b) constitutes the other end of the coil 2. The wire end 3a is linearly led outward along the Y-axis direction from the lower end of the coil 2 (the winding portion of the coil 2). The wire end 3b is led outward along the Y-axis direction from the upper end of the coil 2 (the winding portion of the coil 2), and is led downward along the Z-axis direction. That is, the wire end 3b is bent and led from the Y-axis direction to the Z-axis direction, and is bent and led from the Z-axis direction to the Y-axis direction. Neither of the wire ends 3a and 3b is twisted, and they are led out in the same direction (Y-axis direction) as each other.

[0076] like Figure 4 As shown, the terminals 4a and 4b are formed to be mirror-symmetrical with respect to the YZ plane. Figure 5A As shown, the terminals 4a and 4b are arranged (mounted) at a predetermined interval in the X-axis direction on the upper surface of the base 50. The terminals 4a are arranged on one side of the base 50 in the X-axis direction, and the terminals 4b are arranged on the other side of the base 50 in the X-axis direction. The terminals 4a and 4b are formed, for example, by machining a metal plate, but the method of forming the terminals 4a and 4b is not limited thereto.

[0077] like Figure 4 As shown, the terminals 4 a and 4 b have a first mounting portion 41 , a second mounting portion 42 , a first positioning portion 43 , a fourth positioning portion 44 , a wiring portion 45 , a mounting portion 46 , a connecting portion 47 and a cutout portion 48 .

[0078] The mounting portion 46 is fixed to Figure 1 The mounting portion 46 has a predetermined width in the Y-axis direction and is fixed to the region from one end to the other end of the bottom surface of the second magnetic core 6 in the Y-axis direction. In addition, the mounting portion 46 has a predetermined width in the X-axis direction and is fixed to the end of the bottom surface of the second magnetic core 6 in the X-axis direction. The mounting portion 46 is connected to a circuit board (not shown) by solder or a conductive adhesive.

[0079] The connecting portion 47 is integrally connected to the mounting portion 46 and extends in a substantially perpendicular direction relative to the mounting portion 46. The connecting portion 47 is a portion that connects the mounting portion 46 and the placement portions 41 and 42 and is fixed to the mounting portion 46. Figure 1The outer side surface of the second magnetic core 6 shown in FIG. The connecting portion 47 extends along the outer side surface of the second magnetic core 6 to the opposite side (the negative side of the Z axis) of the first magnetic core 5. The connecting portion 47 of the terminal 4a and the connecting portion 47 of the terminal 4b are arranged opposite to each other in the X axis direction. When the mounting portion 46 is connected to a circuit board (not shown) by soldering, a solder fillet is formed on a part of the connecting portion 47. That is, the connecting portion 47 also functions as a solder fillet forming portion.

[0080] The first loading portion 41 and the second loading portion 42 are integrally connected to the end of the connecting portion 47 in the Z-axis direction, and extend in a direction substantially perpendicular to the connecting portion 47 (the same direction as the extending direction of the mounting portion 46: the X-axis direction). The loading portions 41 and 42 have surfaces substantially parallel to the upper surface of the first magnetic core 5 (base 50), and face the mounting portion 46 in the Z-axis direction. The loading portions 41 and 42 are placed on the upper surface of the base 50 (see Figure 5A ), sandwiched between the first magnetic core 5 and the second magnetic core 6 (refer to Figure 1 ).

[0081] The placement parts 41 and 42 disposed on the base 50 are covered by the first magnetic core 5 (base 50) and the second magnetic core 6, so the terminals 4a and 4b can be fixed to the above-mentioned magnetic cores 5 and 6 via the placement parts 41 and 42. That is, the placement parts 41 and 42 function as fixing parts for fixing the terminals 4a and 4b to the magnetic cores 5 and 6.

[0082] In more detail, Figure 2 and Figure 4 As shown, the first carrier portion 41 of the terminal 4a is arranged in the third recess 51c, the second carrier portion 42 of the terminal 4a is arranged in the fourth recess 51d, the first carrier portion 41 of the terminal 4b is arranged in the second recess 51b, and the second carrier portion 42 of the terminal 4b is arranged in the first recess 51a.

[0083] like Figure 4 As shown, the first loading portion 41 is formed at one end of the terminals 4a and 4b in the Y-axis direction, and the second loading portion 42 is formed at the other end of the terminals 4a and 4b in the Y-axis direction. The first loading portion 41 and the second loading portion 42 are arranged at a predetermined interval in the Y-axis direction, and a cutout portion 48 is formed between the loading portions 41 and 42 to separate them. Figure 1 As shown, the cutout portion 48 is formed at least at the position where the terminals 4a and 4b are exposed outside the first magnetic core 5 and the second magnetic core 6. Figure 4 In the example shown, it extends from the front end of the placement parts 41, 42 to the lower end of the connection part 47. Since the terminals 4a, 4b have the cutouts 48, the terminals 4a, 4b can be easily bent at the intersection of the placement parts 41, 42 and the connection part 47.

[0084] like Figure 5A As shown, when the terminals 4a and 4b are arranged on the upper surface of the base 50, the fourth protrusion 52d is arranged in the region where the cutout 48 is formed of the terminal 4a, and the second protrusion 52b is arranged in the region where the cutout 48 is formed of the terminal 4b.

[0085] like Figure 4 As shown, the connection portion 45 is formed integrally with the end portion of one side of the first carrier portion 41 in the Y-axis direction. Figure 3 The end of the coil 2 is shown. The connection portion 45 of the terminal 4a and the connection portion 45 of the terminal 4b are arranged to face the same direction (Y-axis direction) with each other.

[0086] The connection portion 45 includes a fixing piece 45a and a bent piece 45b. The fixing piece 45a is opposite to the bent piece 45b in the Z-axis direction and is formed integrally with the end portion of the first mounting portion 41 on one side in the Y-axis direction. The fixing piece 45a has a shape that is an extension of the first mounting portion 41 to one end side in the Y-axis direction and is mounted on the upper surface of the base 50 (see FIG. 1 ) in the same manner as the first mounting portion 41. Figure 5A ).

[0087] The bending piece 45b is formed integrally with the end of the other side of the fixing piece 45a in the X-axis direction, and is formed so that the end can be bent as a bending point (fulcrum). The bending piece 45 is formed in a manner of standing in the Z-axis direction before it is bent, and is formed in a manner of extending to one side of the X-axis direction as shown in the figure after it is bent. The bending piece 45b of the terminal 4a and the bending piece 45b of the terminal 4b extend in a direction approaching each other. The bending piece 45b and the fixing piece 45a are configured to be opposite to each other on the upper surface of the base 50.

[0088] like Figure 5A As shown, the connection part 45 of the terminal 4a holds the wire end 3a of the wire 3 by its fixing piece 45a and the bending piece 45b. In addition, the connection part 45 of the terminal 4b holds the wire end 3b of the wire 3 by its fixing piece 45a and the bending piece 45b.

[0089] The connection portion 45 is arranged on the surface of the base portion 50 in the same manner as the placement portions 41 and 42, and is Figure 1 The first magnetic core 5 and the second magnetic core 6 are shown. When the connection portion 45 is used to hold the long side surface of the wire ends 3a and 3b of the wire 3, the holding surface is arranged substantially parallel to the upper surface of the base 50. In addition, the holding surface (contact surface) of the wire ends 3a and 3b of the fixing piece 45a, the holding surface (contact surface) of the wire ends 3a and 3b of the bending piece 45b, and the long side surface of the wire ends 3a and 3b are arranged substantially parallel.

[0090] like Figure 4As shown, a first positioning portion 43 is formed at an end portion of one side of the first carrier portion 41 in the X-axis direction. The first positioning portion 43 is bent with the edge of the first carrier portion 41 at its end as a bending point (fulcrum) and extends in the Z-axis direction. The first positioning portion 43 is formed on the side opposite to the side of the bending point where the bending piece 45b is configured. The first positioning portion 43 of the terminal 4a and the first positioning portion 43 of the terminal 4b are opposite to each other in the X-axis direction.

[0091] like Figure 5B As shown, the first positioning portion 43 of the terminal 4a is formed around the wire end 3a, and the first positioning portion 43 of the terminal 4b is formed around the wire end 3b. The first positioning portion 43 of the terminal 4a and the first positioning portion 43 of the terminal 4b are arranged between each of a pair of ends (wire ends 3a, 3b) of the coil 2. More specifically, the first positioning portion 43 of the terminal 4a is arranged around the intersection where the wire end 3a and the outer peripheral surface of the coil 2 intersect, and the first positioning portion 43 of the terminal 4b is arranged around the intersection where the wire end 3b and the outer peripheral surface of the coil 2 intersect.

[0092] The distance L1 between the first positioning portion 43 of the terminal 4a and the first positioning portion 43 of the terminal 4b is smaller than the outer diameter D of the coil 2 (the same applies to the distance L2 described later). In the example shown in the figure, the distance L1 is substantially equal to the distance between the wire ends 3a and 3b or the inner diameter of the coil 2.

[0093] like Figure 4 As shown, a second positioning portion 44 is formed at the end of the second carrier portion 42 on the other side in the Y-axis direction. The second carrier portion 42 is located on the opposite side of the wiring portion 45 along the Y-axis direction. The second positioning portion 44 is bent with the edge of the second carrier portion 42 at the end as a bending point (fulcrum) and extends in the Z-axis direction. The second positioning portion 44 of the terminal 4a and the second positioning portion 44 of the terminal 4b are oriented toward Figure 1 The side surface of the second magnetic core 6 shown (the side surface perpendicularly intersecting the Y axis and to which the terminals 4a and 4b are not fixed).

[0094] The positioning parts 43 and 44 are respectively formed in a protrusion shape. The length of the positioning parts 43 and 44 in the Z-axis direction is not particularly limited, and is about 1 / 4 to 3 / 4 of the length of the bent piece 45b along the long side direction. In addition, the length of the positioning parts 43 and 44 in the Z-axis direction is preferably 1 / 8 to 1 / 4 of the height of the coil 2.

[0095] like Figure 5BAs shown, the first positioning portion 43 of the terminal 4a is arranged at a position offset inwardly in the X-axis direction relative to the second positioning portion 44 of the terminal 4a, and the first positioning portion 43 of the terminal 4b is arranged at a position offset inwardly in the X-axis direction relative to the second positioning portion 44 of the terminal 4b. Therefore, the distance L1 between the first positioning portion 43 of the terminal 4a and the first positioning portion 43 of the terminal 4b is smaller than the distance L2 between the second positioning portion 44 of the terminal 4a and the second positioning portion 44 of the terminal 4b.

[0096] When the coil 2 and the terminals 4a and 4b are arranged on the upper surface of the base 50, the positioning parts 43 and 44 of the terminal 4a and the positioning parts 43 and 44 of the terminal 4b are arranged near the outer periphery of the coil 2. Thus, the position of the coil 2 is restricted relative to the terminals 4a and 4b (movement in the X-axis direction, the Y-axis direction, and the rotational direction), and the coil 2 can be positioned relative to the terminals 4a and 4b.

[0097] In this embodiment, the positioning portions 43 and 44 do not abut against the outer peripheral surface of the coil 2. More specifically, a gap G1 is formed between the first positioning portion 43 of the terminal 4a and the outer peripheral surface of the coil 2, a gap G2 is formed between the first positioning portion 43 of the terminal 4b and the outer peripheral surface of the coil 2, a gap G3 is formed between the second positioning portion 44 of the terminal 4a and the outer peripheral surface of the coil 2, and a gap G4 is formed between the second positioning portion 44 of the terminal 4b and the outer peripheral surface of the coil 2.

[0098] When the gap width of gap G1 is set to L3, the gap width of gap G2 is set to L4, the gap width of gap G3 is set to L5, and the gap width of gap G4 is set to L6, L3 = L4 = L5 = L6 may be satisfied, and the values ​​of L3 to L6 may not all be equal. For example, L3 = L4 > L5 = L6 may be satisfied, or L5 = L6 > L3 = L4 may be satisfied.

[0099] When the center of the columnar portion 53 is substantially aligned with the center of the coil 2, the gap width L7 between the outer peripheral surface of the columnar portion 53 and the inner peripheral surface of the coil 2 is larger than the gap widths L3 to L6 of the gaps G1 to G4. More specifically, the gap width L7 is larger than the average value of the gap widths L3 to L6, or larger than the maximum value of the distances L3 to L6.

[0100] Furthermore, the bent piece 45b of the connection portion 45 stands upright in the Z-axis direction before being bent, and in this state, the coil 2 (more specifically, the wire ends 3a and 3b of the wire 3 constituting the ends of the coil 2) can be positioned. That is, the bent piece 45b of the connection portion 45 of the terminals 4a and 4b also functions as a positioning portion before being bent.

[0101] like Figure 5AAs shown, in a state where terminals 4a and 4b are arranged on the upper surface of the base 50, the coil 2 is arranged (carried) in a manner spanning the first carrying portion 41 and the second carrying portion 42 of the terminal 4a, the first carrying portion 41 and the second carrying portion 42 of the terminal 4b, and the first protrusion 52a to the fourth protrusion 52d of the base 50.

[0102] In this embodiment, around the connection portion 45, the connection portion 45 (more precisely, the fixing piece 45a) of the terminals 4a and 4b is arranged on the first core 5 (base 50), and the connection portion 45 (more precisely, the bent piece 45b) is arranged on the connection portion 45. Figure 1 The second magnetic core 6 is shown.

[0103] As mentioned above, there is a step between the configuration position of the wiring portion 45 (fixing piece 45a) and the configuration position of the coil 2, but the height of the step is about the same as the plate thickness of the terminals 4a and 4b and is relatively small. Therefore, the wiring portion 45 (fixing piece 45a) and the coil 2 are actually configured on approximately the same plane of the base 50.

[0104] like Figure 1 and Figure 5A As shown, the second magnetic core 6 is formed in a manner covering the upper surface of the coil 2 and the base 50. The second magnetic core 6 is formed, for example, by embedding a temporary assembly obtained by combining the coil 2 formed by connecting the terminals 4a, 4b to each end and the first magnetic core 5 into the interior of a mold and performing injection molding. However, as the second magnetic core 6, a pre-formed magnetic core (pre-formed magnetic core) may also be used. The second magnetic core 6 may be made of the same type of material as the first magnetic core 5, or may be made of a different type of material. In addition, the second magnetic core 6 may also be made of resin alone.

[0105] When the second magnetic core 6 is combined with the first magnetic core 5 , the coil 2 and a part of the terminals 4 a and 4 b (the placement portions 41 and 42 , the positioning portions 43 and 44 , and the connection portion 45 ) are covered by the second magnetic core 6 .

[0106] Next, refer to Figure 6A to Figure 6E In the method of this embodiment, first, a conductive plate such as a metal plate (for example, a Sn-plated metal plate) is punched into a Fig. 6A As shown in the figure, terminals 4a and 4b connected to the frame 7 via connecting portions 47 are formed on the conductive plate after punching.

[0107] Next, to Figure 3The ends of the coil 2 shown (the wire ends 3a, 3b of the wire 3) are connected to the terminals 4a, 4b. At this time, the position of the coil 2 relative to the terminals 4a, 4b is restricted by the positioning parts 43, 44 of the terminals 4a, 4b, and a part of the bottom surface of the coil 2 is placed on the placement parts 41, 42 of the terminals 4a, 4b. More specifically, with respect to the outer peripheral surface of the coil 2, in order to form a predetermined gap inside the positioning parts 43, 44 of the terminal 4a and the positioning parts 43, 44 of the terminal 4b, a part of the bottom surface of the coil 2 is placed on the placement parts 41, 42 of the terminals 4a, 4b. Then, the wire ends 3a, 3b are clamped (held) by the fixing part 45a and the bending piece 45b, and the wire ends 3a, 3b are connected to the connection part 45.

[0108] Then, if Figure 6B As shown, the coil 2 is combined with the terminals 4a and 4b fixed to each end. Figure 2 The first magnetic core 5 shown constitutes a temporary assembly. In more detail, the columnar portion 53 of the first magnetic core 5 is inserted into the inner side of the coil 2, and the respective mounting portions 41 and 42 of the terminals 4a and 4b are placed on the upper surface of the base 50. At this time, a portion of the bottom surface of the coil 2 is placed on the protrusions 52a to 52d of the base 50. As the first magnetic core 5, a preformed magnetic core (preformed magnetic core) is used. As a material constituting the first magnetic core 5, a material with fluidity is used, and a composite magnetic material in which a thermoplastic resin or a thermosetting resin is used as a binder can be used.

[0109] Before or after forming the temporary assembly (i.e., Fig. 6A or Figure 6B In the state shown in the figure, laser welding is performed on the connection part 45. The laser welding is performed by irradiating the bent piece 45b with laser light from above the connection part 45. A laser ball (not shown) is formed at the portion irradiated with laser light.

[0110] Next, Figure 6B The temporary assembly shown is inserted into the mold, and the second magnetic core 6 is formed by injection molding in the mold. At this time, the connection portion 47 of the terminals 4a and 4b is exposed from the mold. During injection molding, a mixture containing magnetic powder and a binder resin is fluidized by heating, etc., injected into the mold, and solidified by cooling, etc., thereby obtaining Figure 6C The second magnetic core 6 is shown.

[0111] In the example shown in the figure, a step portion 60 is formed on the surface of the second core 6 so as to extend across the side and bottom surfaces thereof. The mounting portion 46 ( Figure 4), the connection portion 47 of the terminal portions 4a and 4b can be arranged on a part of the step portion 60 formed on the side surface of the second magnetic core 6.

[0112] Then, if Fig.6D As shown, Figure 6C The frame 7 shown is cut off and removed using a cutting tool, such as Fig. 6E As shown in FIG. 4 , the remaining portion (connection portion 47) is fixed to the step portion 60. In more detail, as shown in FIG. Fig. 6E As shown, the connecting portion 47 of the terminals 4a and 4b is connected from Fig.6D In the state shown, the connecting portion 47 is bent substantially vertically and fixed to a part of the step portion 60 formed on the side surface of the second magnetic core 6. In addition, in this state, the front end portion of the connecting portion 47 is bent substantially vertically and fixed to a part of the step portion 60 formed on the bottom surface of the second magnetic core 6. As described above, the inductor 1 of this embodiment can be obtained.

[0113] The inductor 1 of this embodiment has protrusions (first positioning portion 43 and second positioning portion 44) that restrict the position of the coil 2 formed on the terminals 4a and 4b. Therefore, when the ends (wire ends 3a and 3b) of the coil 2 are connected to the terminals 4a and 4b, the position of the coil 2 relative to the terminals 4a and 4b is restricted by the positioning portions 43 and 44, and the position of the coil 2 relative to the terminals 4a and 4b can be prevented. In addition, in this state, when the terminals 4a and 4b are arranged at a predetermined position of the first magnetic core 5 together with the coil 2, the coil 2 can be smoothly inserted into the columnar portion (winding core portion) 53 of the first magnetic core 5, and the columnar portion 53 can be prevented from contacting the inner peripheral surface of the coil 2. Therefore, according to this embodiment, the inductance characteristics of each product can be prevented from varying due to this defect, and the inductor 1 with high reliability can be realized. In addition, by preventing such a defect, the inductor 1 can be easily manufactured.

[0114] In this embodiment, the positioning portions 43 and 44 are arranged near the outer periphery of the coil 2. Therefore, the deviation width of the position of the coil 2 relative to the terminals 4a and 4b can be reduced, and the displacement of the coil 2 relative to the terminals 4a and 4b can be effectively prevented.

[0115] In addition, in the present embodiment, the positioning portions 43 and 44 do not abut against the outer peripheral surface of the coil 2. Therefore, when an insulating film is formed on the outer surface of the coil 2, damage to the insulating film due to friction with the positioning portions 43 and 44 can be prevented, and a short circuit failure is not likely to occur between the terminals 4a and 4b and the coil 2 (the outer peripheral surface of the coil 2).

[0116] In addition, the present embodiment includes the first core 5 including the columnar portion 53 inserted into the coil 2. Therefore, the effective magnetic permeability of the first core 5 in the region inside the coil 2 can be sufficiently ensured, and the inductance characteristics of the inductor 1 can be improved.

[0117] In addition, in this embodiment, if Figure 5B As shown, the distance L7 between the outer circumference of the columnar portion 53 and the inner circumference of the coil 2 is greater than the distances L3 to L6 between the positioning portions 43 and 44 and the outer circumference of the coil 2. In this case, a first gap is formed between the outer circumference of the columnar portion 53 and the inner circumference of the coil 2, and a second gap (gaps G1 to G4) is formed between the positioning portions 43 and 44 and the outer circumference of the coil 2. Assuming that the coil 2 is arranged in a position offset relative to the terminals 4a and 4b within the range of the gap G1, a gap corresponding to the difference between the first gap and the second gap (i.e., a gap consisting of the width of L7-L3 to L7+L3) is formed between the outer circumference of the columnar portion 53 and the inner circumference of the coil 2. Therefore, even if the coil 2 is arranged in a position offset relative to the terminals 4a and 4b within the range of the second gap, a gap is still formed between the outer circumference of the columnar portion 53 and the inner circumference of the coil 2, and the columnar portion 53 does not contact the inner circumference of the coil 2, and the coil 2 can be inserted into the columnar portion 53 without causing problems such as the columnar portion 53 and the inner circumference of the coil 2.

[0118] In addition, in the present embodiment, the first positioning portion 43 of the terminal 4a and the first positioning portion 43 of the terminal 4b are arranged between the pair of ends (conductor ends 3a, 3b) of the coil 2. Therefore, the positions of the winding portion and each end (conductor ends 3a, 3b) of the coil 2 can be restricted by using the first positioning portion 43 of each of the terminals 4a and 4b, and the displacement of the coil 2 relative to the terminals 4a and 4b can be effectively prevented.

[0119] In addition, in this embodiment, if Figure 5B As shown, the distance L1 between the first positioning portion 43 of the terminal 4a and the first positioning portion 43 of the terminal 4b is smaller than the outer diameter D of the coil 2. Therefore, the displacement of the coil 2 relative to the terminals 4a and 4b in the positive direction of the Y axis and the displacement of the coil 2 in the X axis direction can be prevented.

[0120] In this embodiment, the protrusion (bent piece 45b) functions as the connection portion 45 of the terminals 4a and 4b. Therefore, the lead ends 3a and 3b can be connected to the connection portion 45, and the protrusion (bent piece 45b) can prevent the coil 2 from being displaced relative to the terminals 4a and 4b.

[0121] Second embodiment

[0122] The inductor 101 according to the second embodiment of the present invention is different only in the following points, and the other structures are the same as those of the first embodiment described above. Hereinafter, the same reference numerals are given to the same parts as those of the first embodiment, and detailed description thereof will be omitted.

[0123] contrast Figure 1 and Figure 7 It can be seen that the inductor 101 of the present embodiment is different from the inductor 1 of the first embodiment in that it has terminals 8 a and 8 b instead of the terminal 4 a , has a first magnetic core 9 instead of the first magnetic core 5 , and has a coil 102 instead of the coil 2 .

[0124] like Figure 8 As shown in FIG. 1 , the first magnetic core 9 has a base 90 and a columnar portion 91 formed on the surface (upper surface) of the base 90. The first magnetic core 9 and the second magnetic core 6 are joined on substantially the same plane. Figure 7 As shown, when the inductor 101 is arranged with the mounting surface facing downward, the upper surface of the base 90 faces downward of the inductor 101 .

[0125] The base 90 is formed in a substantially rectangular parallelepiped shape (substantially flat shape), and its surface (upper surface) is formed in a flat surface. Figure 7 The second magnetic core 6 shown is covered. A recess 92 is formed on each side surface (each end) of the base 90 in the X-axis direction. The depth of the recess 92 in the X-axis direction is not particularly limited, and can be, for example, the same as the plate thickness of the terminals 8a and 8b, or greater than that. The Y-axis width of the recess 92 is about 1 / 2 to 2 / 3 of the Y-axis width of the base 90, and is Figure 7 The terminals 8a, 8b shown have substantially the same width in the Y-axis direction.

[0126] The columnar portion 91 is formed integrally with the substantially central portion of the base portion 90 and extends in the Z-axis direction. Figure 7 The coil (air-core coil) 102 shown. Therefore, the diameter of the columnar portion 91 is smaller than the inner diameter of the coil 102. The columnar portion 91 is formed in a cylindrical shape, and its height is higher than the height of the coil 102. By providing the first magnetic core 9 with the columnar portion 91, the effective magnetic permeability of the first magnetic core 9 in the area inside the coil 102 can be sufficiently ensured, and the inductance characteristics of the inductor 101 can be improved.

[0127] like Fig. 9As shown, the coil 102 is composed of an air-core coil, which is formed by flatly winding the conductor 3 composed of a flat wire. In this embodiment, the coil 102 is α-wound. The surface on the long side of the conductor 3 (the surface in the width direction) constitutes the inner peripheral surface or the outer peripheral surface of the coil 102, and the width direction of the conductor 3 is roughly parallel to the winding axis direction of the coil 102. The surface on the short side of the conductor 3 (the surface on the edge side) faces the Z-axis direction. The coil 102 is placed on Fig.11 The upper surface of the base 90 is shown.

[0128] The lead end 3a of the lead 3 is bent into a substantially L-shape and is linearly led outward from the upper end of the coil 102 (the winding portion of the coil 102) along the Y-axis direction. The lead end 3b of the lead 3 is bent into a substantially L-shape and is linearly led outward from the lower end of the coil 102 (the winding portion of the coil 102) along the Y-axis direction. The front end of the lead end 3a and the front end of the lead end 3b extend to opposite sides along the X-axis direction.

[0129] like Fig.10 As shown, the terminals 8a and 8b have a first loading portion 81, a second loading portion 82, a wiring portion 83, a mounting portion 84, a connecting portion 85, a cutout portion 86, and a fixing hole 87. In addition, the structures of the first loading portion 81, the second loading portion 82, the mounting portion 84, the connecting portion 85, and the cutout portion 86 are respectively the same as the structures of the first loading portion 41, the second loading portion 42, the mounting portion 46, the connecting portion 47, and the cutout portion 48 of the first embodiment, and therefore, a detailed description thereof is omitted.

[0130] The connection portion 83 is formed integrally with the end portion of one side of the first carrier portion 81 in the Y-axis direction. The width of the connection portion 83 in the X-axis direction is narrower than the width of the first carrier portion 81 in the X-axis direction, thereby achieving miniaturization of the connection portion 83. Fig. 9 The end of the coil 102 shown. The connection portion 83 of the terminal 8a and the connection portion 83 of the terminal 8b are arranged to face the same direction (Y-axis direction) with each other. Therefore, when laser welding is performed on each connection portion 83, 83, for example, it is easy to irradiate the laser from the positive direction side of the Y-axis to each connection portion 83, 83, which can facilitate manufacturing.

[0131] like Fig.11 As shown, the connection portion 83 of the terminal 8b is arranged at the second magnetic core 6 ( Figure 7) is arranged on the outside (X-axis positive direction side) of an imaginary line L which is parallel to the side surface of the second magnetic core 6 (the side surface which intersects the X-axis perpendicularly and to which the terminal 8b is fixed) and in contact with the outer periphery of the coil 102. In the example shown in the figure, the imaginary line L is parallel to the lead-out direction of the wire end 3b of the wire 3 and passes through the wire end 3b. Although the detailed illustration is omitted, the connection portion 83 of the terminal 8a is also arranged on the outside (X-axis negative direction side) of the imaginary line which is parallel to the side surface of the second magnetic core 6 (the side surface which intersects the X-axis perpendicularly and to which the terminal 8a is fixed) and in contact with the outer periphery of the coil 102.

[0132] In the case of connecting with the second magnetic core 6 ( Figure 7 ), when viewed from a direction perpendicular to the side surface of the second magnetic core 6 (the side surface to which the terminal 8a is fixed), the connection portion 83 of the terminal 8a and the remaining portion of the terminal 8a other than the connection portion 83 (the mounting portions 81, 82, the mounting portion 84, the connecting portion 85, etc.) are arranged to be offset in the Y-axis direction. Similarly, when viewed from a direction perpendicular to the side surface of the second magnetic core 6 (the side surface to which the terminal 8b is fixed), the connection portion 83 of the terminal 8b and the remaining portion of the terminal 8b other than the connection portion 83 (the mounting portions 81, 82, the mounting portion 84, the connecting portion 85, etc.) are arranged to be offset in the Y-axis direction.

[0133] like Fig.10 As shown, the connection portion 83 includes a fixing piece 83a and a bending piece 83b. The fixing piece 83a is opposite to the bending piece 83b in the Y-axis direction and is formed integrally with the end of one side in the Y-axis direction of the first carrier portion 81. The fixing piece 83a is bent upward with the end of one side in the Y-axis direction of the first carrier portion 81 as a bending point (fulcrum).

[0134] The length of the fixing piece 83a of the terminal 8a in the Z-axis direction is longer than the length of the fixing piece 83a of the terminal 8b in the Z-axis direction, and is longer than the length of the bending piece 83b of the terminal 8a in the Z-axis direction. The length of the fixing piece 83a of the terminal 8b in the Z-axis direction is approximately equal to the length of the bending piece 83b of the terminal 8b in the Z-axis direction.

[0135] The bent piece 83b is formed integrally with the end of one side of the fixed piece 83a in the Z-axis direction, and is bent downward with the end as a bending point (fulcrum). Both the fixed piece 83a and the bent piece 83b are formed to extend in the Z-axis direction, and are arranged in a direction perpendicular to the upper surface of the base 90. When manufacturing the inductor 101, the outer surface of the bent piece 83b in the Y-axis direction is irradiated with laser, and this surface functions as a laser irradiation surface.

[0136] like Fig.11As shown in the figure, the connection portion 83 of the terminal 8a holds the wire end 3a of the wire 3 by its fixing piece 83a and the bent piece 83b. The wire end 3a of the wire 3 is led out from the upper end of the coil 102, so the connection portion 83 of the terminal 8a holds the wire end 3a above the upper surface of the base 90. The connection portion 83 of the terminal 8a is buried inside the second magnetic core 6. In addition, the bent piece 83b of the terminal 8a is bent in the vertical direction relative to the fixing piece 85a before clamping the wire end 3a, and extends along the Y-axis direction.

[0137] The connection portion 83 of the terminal 8b holds the wire end 3b of the wire 3 by clamping it with the fixing piece 83a and the bent piece 83b. The wire end 3b of the wire 3 is led out from the lower end of the coil 102, so the connection portion 83 of the terminal 8b holds the wire end 3b while being placed on the upper surface of the base 90. The connection portion 83 of the terminal 8b is clamped by the first magnetic core 9 and the second magnetic core 6. In addition, the bent piece 83b of the terminal 8b is bent in the vertical direction relative to the fixing piece 85a before clamping the wire end 3b, and extends along the Y-axis direction.

[0138] like Fig.10 and Fig.11 As shown, the connection portion 83 has a holding surface 830 for holding the end of the coil 102. The holding surface 830 is a portion corresponding to the contact surface between the fixing piece 83a and the surface on the long side of the wire ends 3a and 3b, or the contact surface between the bending piece 83b and the surface on the long side of the wire ends 3a and 3b. The holding surface 830 of the connection portion 83 of the terminal 8a and the holding surface 830 of the connection portion 83 of the terminal 8b face the same direction (Y-axis direction).

[0139] When the connecting portion 83 is used to hold the long side surfaces of the wire ends 3a and 3b of the wire 3, the holding surface 830 is relative to Figure 7 The side surfaces of the second core 6 shown (the side surfaces perpendicularly intersecting the Y axis and not fixed to the terminals 8a and 8b) are arranged substantially parallel and substantially perpendicular to the upper surface of the base 90. However, the retaining surface 830 may be arranged slightly inclined relative to the above-mentioned side surfaces of the second core 6.

[0140] The holding surface 830 is arranged in a manner substantially parallel to the winding axis of the coil 102. The clamping direction when the wire ends 3a, 3b of the wire 3 are clamped by the fixing piece 83a and the bending piece 83b is substantially perpendicular to the winding axis of the coil 102 and substantially perpendicular to the holding surface 830 (the normal direction of the holding surface 830).

[0141] The retaining surface 830 (contact surface) of the wire ends 3a and 3b of the fixing plate 83a, the retaining surface 830 (contact surface) of the wire ends 3a and 3b of the bending plate 83b, and the surfaces on the long sides of the wire ends 3a and 3b are arranged roughly parallel, and are all opposite to the side surfaces of the second magnetic core 6 (the side surfaces intersecting the Y-axis perpendicularly).

[0142] like Fig.10 As shown, fixing holes (openings) 87 are respectively formed in the first mounting portion 81 and the second mounting portion 82. When the second magnetic core 6 is formed, the material forming the second magnetic core 6 (including a mixture of magnetic powder and binder resin) enters the fixing holes 87 inside the mold, thereby the terminals 8a and 8b can be firmly fixed to the second magnetic core 6.

[0143] like Fig.11 As shown, the connection portion 83 and the coil 102 are arranged on substantially the same plane of the base 90. In this embodiment, around the connection portion 83, the connection portion 83 of the terminals 8a and 8b is arranged above the first magnetic core 9 (base 90), and the connection portion 83 is arranged above the connection portion 83. Figure 7 The second magnetic core 6 shown. Therefore, the connection portion 83 can be arranged between the first magnetic core 9 and the second magnetic core 6, which can effectively protect the connection portion 83 from external factors such as external force and prevent the occurrence of poor opening. In addition, by arranging the connection portion 83 on the first magnetic core 9, it is possible to prevent the connection portion 83 from being misaligned when the second magnetic core 6 is arranged on the connection portion 83.

[0144] Next, refer to Figures 12A to 12E In the method of this embodiment, first, a conductive plate such as a metal plate (for example, a Sn-plated metal plate) is punched into a Fig. 12A As shown in the figure, terminals 8a and 8b connected to the frame 7 via connecting portions 85 are formed on the conductive plate after punching.

[0145] Then, in Fig. 9 The ends of the coil 102 shown (the wire ends 3a, 3b of the wire 3) are connected to the terminals 8a, 8b. More specifically, the coil 102 is arranged between the terminals 8a and 8b, the wire ends 3a, 3b are clamped (held) by the fixing portion 83a and the bent piece 83b, and the wire ends 3a, 3b are connected to the connection portion 83.

[0146] Then, if Fig. 12B As shown, a coil 102 having terminals 8a and 8b fixed at each end is assembled. Figure 8The first magnetic core 9 shown in the figure constitutes a temporary assembly. More specifically, the columnar portion 91 of the first magnetic core 9 is inserted into the inner side of the coil 102, and the coil 102 is placed on the upper surface of the base 90. In addition, the respective placement portions 81 and 82 of the terminals 8a and 8b are placed on the upper surface of the base 90. As the first magnetic core 9, a pre-formed magnetic core (temporarily formed magnetic core) is used.

[0147] Before or after forming the temporary assembly (i.e., Fig. 12A or Fig. 12B The connection portion 83 is laser welded. The laser welding is performed by, for example, irradiating the bending piece 83b with laser light from the side of the connection portion 83 (in a direction perpendicular to the bending piece 83b). A laser ball (not shown) is formed at the portion irradiated with laser light.

[0148] Next, Fig. 12B The temporary assembly shown is inserted into the mold, and the second magnetic core 6 is formed by injection molding in the mold. At this time, the connection portion 85 of the terminals 8a and 8b is exposed from the mold. During injection molding, a mixture containing magnetic powder and a binder resin is fluidized by heating, etc., injected into the mold, and solidified by cooling, etc., thereby obtaining Fig. 12C The second magnetic core 6 shown in FIG. 1 . At this time, the mixture enters the interior of the fixing holes 87 of the terminals 8a and 8b, so that the terminals 8a and 8b can be fixed to the second magnetic core 6 with sufficient fixing strength.

[0149] exist Fig. 12C In the example shown, a step portion 60 is formed on the surface of the second core 6 so as to extend across the side and bottom surfaces thereof. The mounting portion 84 ( Fig.10 ), the connection portion 85 of the terminal portions 8a and 8b can be arranged on a part of the step portion 60 formed on the side surface of the second magnetic core 6.

[0150] Then, if Fig.12D As shown, Fig. 12C The frame 7 shown is cut off and removed using a cutting tool, such as Fig.12E As shown in FIG. 8 , the remaining portion (connection portion 85) is fixed to the step portion 60. In more detail, as shown in FIG. Fig.12E As shown, the connecting portion 85 of the terminals 8a and 8b is connected from Fig.12D In the state shown, the connecting portion 85 is bent substantially vertically and fixed to a part of the step portion 60 formed on the side surface of the second magnetic core 6. In addition, in this state, the front end portion of the connecting portion 85 is bent substantially vertically and fixed to a part of the step portion 60 formed on the bottom surface of the second magnetic core 6. As described above, the inductor 101 of this embodiment can be obtained.

[0151] In the inductor 101 of the present embodiment, the holding surface 830 of the connection portion 83 extends parallel to the winding axis of the coil 102. In the coil 102 formed by flatly winding a flat wire, the surface of the long side of the end portion (the wire ends 3a and 3b of the wire 3) also extends parallel to the winding axis. Therefore, when the wire ends 3a and 3b are drawn out from the winding portion of the coil 102, even if the wire ends 3a and 3b are not twisted, the surface of the long side can be aligned with the direction of the holding surface 830 of the connection portion 83. Therefore, the wire ends 3a and 3b can be held by the holding surface 830 without being twisted, and the inductance characteristics of the inductor 101 can be prevented from being uneven, thereby realizing the inductor 101 with high reliability.

[0152] In addition, in the present embodiment, the holding surface 830 faces the side surface (the side surface perpendicularly intersecting the Y-axis) of the second magnetic core 6. Therefore, when laser welding is performed on the connecting portion 83 (holding surface 830), for example, it is easy to irradiate the inductor 101 with laser light in the Y-axis direction from the side, which can facilitate manufacturing.

[0153] In addition, in the present embodiment, the lead ends 3a and 3b are bent into a substantially L-shape. Therefore, the long-side surfaces of the lead ends 3a and 3b can be easily opposed to the side surfaces (side surfaces perpendicularly intersecting the Y-axis) of the second magnetic core 6. Therefore, when the lead ends 3a and 3b are held by the holding surface 830 of the connection portion 83, the holding surface 830 is arranged to be opposed to the side surfaces (side surfaces perpendicularly intersecting the Y-axis) of the second magnetic core 6, and it is easy to irradiate the inductor 101 with laser light from the side in the Y-axis direction.

[0154] In addition, in the present embodiment, the connection portion 83 is arranged outside the imaginary line L which is parallel to the side surface (side surface perpendicularly intersecting the X-axis) of the second magnetic core 6 and in contact with the outer periphery of the coil 102. Therefore, the connection portion 83 can be arranged at a position sufficiently separated from the coil 102. Therefore, when laser welding is performed on the connection portion 83, it is possible to prevent a part of the laser from being irradiated to the winding portion of the coil 102, thereby reducing damage to the winding portion of the coil 102. In addition, it is possible to prevent a part of the laser from being irradiated to the first magnetic core 9, thereby also reducing damage to the first magnetic core 9.

[0155] In addition, in the present embodiment, when viewed from a direction perpendicular to the side surface of the second magnetic core 6 (the side surface perpendicularly intersecting the X-axis and to which the terminals 8a and 8b are fixed), the connecting portion 83 and the remaining portions of the terminals 8a and 8b other than the connecting portion 83 (the mounting portions 81 and 82, the mounting portion 84, and the connecting portion 85) are arranged at offset positions. Therefore, the connecting portion 83 can be arranged in a position sufficiently separated from the coil 102 in a direction parallel to the side surface of the second magnetic core 6, and the above-mentioned effect can be obtained when laser welding is performed on the connecting portion 83.

[0156] In addition, in the present embodiment, the magnetic cores 9 and 6 contain magnetic particles and a resin binder. Therefore, it is possible to realize the inductor 101 having good inductance characteristics.

[0157] In addition, in the present embodiment, the holding surface 830 of the terminal 8a and the holding surface 830 of the terminal 8b face the same direction (the positive direction of the Y axis). Therefore, when the connection parts 83 (holding surfaces 830) of the terminals 8a and 8b are subjected to laser welding, for example, it is easy to irradiate the connection parts 83 (holding surfaces 830) with laser, which can facilitate manufacturing.

[0158] Third embodiment

[0159] The inductor 201 according to the third embodiment of the present invention is different only in the following points, and the other structures are the same as those of the first embodiment described above. Hereinafter, the same reference numerals are given to the parts common to the second embodiment, and their detailed descriptions are omitted.

[0160] like Fig.13 As shown in FIG. 1 , the inductor 201 is different from the inductor 101 of the second embodiment in that the inductor 201 has a coil 202 instead of the coil 102 and a terminal 208b instead of the terminal 8b. The terminal 208b is different from the terminal 8b ( Fig.10 The bent piece 85b of the connection portion 83 is opposite to the side surface of the second magnetic core 6 on the other side in the Y-axis direction.

[0161] In the coil 202, one end (conductor end 3a) faces the side surface of the second magnetic core 6 (the side surface intersecting perpendicularly with the Y axis) and is led out in the positive direction of the Y axis. The front end of the conductor end 3a is bent into a substantially L-shape and extends along the X axis. The other end (conductor end 3b) faces the side surface of the second magnetic core 6 (the side surface intersecting perpendicularly with the X axis) and is led out in the negative direction of the X axis. The front end of the conductor end 3b is not bent and extends straight along the X axis.

[0162] In this embodiment, the same effect as in the second embodiment can be obtained. In addition, in this embodiment, the connection portion 83 of the terminal 8a and the connection portion 83 of the terminal 208b are arranged on the diagonal line with the coil 202 sandwiched therebetween. Therefore, the wire end 3b can be held by the connection portion 83 of the terminal 208b arranged opposite to the side surface (side surface perpendicular to the Y axis) of the second magnetic core 6 without being bent into a substantially L-shaped shape and being led out straight. Therefore, it is easy to irradiate the connection portion 83 of the terminal 208b with laser light in the Y-axis direction from the side of the inductor 201.

[0163] In addition, the present invention is not limited to the above-mentioned embodiment, and various changes can be made within the scope of the present invention.

[0164] In the above-described respective embodiments, examples of application of the present invention to inductors are shown, but the present invention can also be applied to coil devices other than inductors.

[0165] In each of the above-mentioned embodiments, the winding shape of the conductive wire 3 is set to a circular spiral shape, but it may be, for example, an elliptical spiral shape or a square spiral shape.

[0166] In the first embodiment described above, the conductive wire 3 is formed of a flat wire, but may be formed of a round wire, a square wire, or a twisted wire.

[0167] In the above-mentioned first embodiment, the connecting portion 45 of the terminal 4 a and the connecting portion 45 of the terminal 4 b may be arranged on a diagonal line with the coil 2 interposed therebetween.

[0168] In the above-described first embodiment, the recessed portions 51 a to 51 d , the convex portions 52 a to 52 d , and the protruding portion 54 may be omitted from the base portion 50 , and the upper surface of the base portion 50 may be formed flat.

[0169] In the first embodiment described above, a part of the upper surface or the side surface of the first core 5 may be covered with the second core 6. The same applies to the second and third embodiments described above.

[0170] In the first embodiment described above, the connection portion 47 of the terminals 4a and 4b may be bent toward the first magnetic core 5. The same applies to the second and third embodiments described above.

[0171] In the above-mentioned first embodiment, the coil 2 is formed by winding the conductive wire 3 vertically, but the coil 2 may be formed by winding the conductive wire 3 horizontally.

[0172] In the first embodiment, openings may be formed in the receiving portions 41 and 42 of the terminals 4a and 4b. With such a structure, when forming the second magnetic core 6, the material forming the second magnetic core 6 (including a mixture of magnetic powder and binder resin) enters the openings inside the mold, and the terminals 4a and 4b can be firmly fixed to the second magnetic core 6.

[0173] In the first embodiment, the positioning portions 43 and 44 of the terminal 4 a and the positioning portions 43 and 44 of the terminal 4 b do not abut against the outer peripheral surface of the coil 2 . However, any one of the four positioning portions 43 and 44 may abut against the outer peripheral surface of the coil 2 .

[0174] In the first embodiment, any of the positioning portions 43 and 44 of the terminal 4a and the positioning portions 43 and 44 of the terminal 4b may be omitted. For example, the second positioning portion 44 may be omitted from the terminals 4a and 4b, or the first positioning portion 43 may be omitted from the terminals 4a and 4b.

[0175] In the first embodiment, the core portion of the inductor 1 is formed by two cores, namely the first core 5 and the second core 6. However, the core portion of the inductor 1 may be formed by only one core. In this case, the core may be formed by powder compacting or injection molding. The same applies to the second and third embodiments.

[0176] In the second embodiment, the holding surface 830 of the connection portion 83 (fixed piece 83a and bent piece 83b) of each terminal 8a, 8b faces the Y-axis direction, but may also face the X-axis direction. That is, the holding surface 830 of the connection portion 83 (fixed piece 83a and bent piece 83b) may also be arranged in a manner substantially parallel to the side surface of the second magnetic core 6 (the side surface perpendicularly intersecting the X-axis and to which the terminals 8a, 8b are fixed). The same is true for the third embodiment.

[0177] In the second embodiment described above, the connecting portion 83 is not limited to Fig.10 The structure shown may be changed in shape as appropriate. For example, the bent piece 83b may be omitted from the connecting portion 83.

[0178] Explanation of symbols

[0179] 1, 101, 201…Inductor (coil device)

[0180] 2. 102, 202… coil

[0181] 3…Wire

[0182] 3a, 3b…Wire end

[0183] 4a, 4b…terminals

[0184] 41 ... first loading portion

[0185] 42 ... second loading portion

[0186] 43…first positioning portion

[0187] 44…Second positioning portion

[0188] 45…Connection

[0189] 45a…fixed plate

[0190] 45b…Bending piece

[0191] 46…Installation

[0192] 47…Connection

[0193] 48…Incision

[0194] 149…Fixing hole

[0195] 5…First core

[0196] 50…base

[0197] 51a~51d…first concave part to fourth concave part

[0198] 52a~52d…the first convex part to the fourth convex part

[0199] 53…Columnar part

[0200] 54…Protrusion

[0201] 6…Second magnetic core

[0202] 60…Step

[0203] 7…Framework

[0204] 8a, 8b, 208b... terminals

[0205] 81 ... first loading portion

[0206] 82 ... second loading portion

[0207] 83…Connection

[0208] 83a…fixed plate

[0209] 83b…Bending sheet

[0210] 830…Keep the surface

[0211] 84…Installation

[0212] 85…Connection

[0213] 86…Incision

[0214] 87…Fixing hole

[0215] 9…First core

[0216] 90…base

[0217] 91…Columnar part

[0218] 92…concave

Claims

1. A coil device, comprising: Air core coil; and a terminal connected to an end of a lead portion led out from the air-core coil, A protrusion is formed on the terminal to limit the position of the air-core coil. The terminal has a fixing piece connected to the lower side of the end of the lead-out portion along the winding axis of the hollow coil; and a bending piece erected from the fixing piece and bent inwardly with the outer side of the end of the lead-out portion as a bending point. The protrusion is located on the opposite side of the bending point across the lead portion, and is arranged closer to the outer periphery of the air-core coil than the bending point.

2. The coil device according to claim 1, wherein: The protrusion does not abut against the outer peripheral surface of the coil.

3. The coil device according to claim 1 or 2, wherein: A magnetic core is provided, the magnetic core including a columnar portion inserted into the air-core coil.

4. The coil device according to claim 3, wherein: A distance between an outer peripheral surface of the columnar portion and an inner peripheral surface of the coil is greater than a distance between the protrusion and an outer peripheral surface of the coil.

5. The coil device according to claim 1 or 2, wherein: having a pair of terminals, The protrusion of one of the terminals and the protrusion of the other terminal are arranged between a pair of end portions of the air-core coil, respectively.

6. The coil device according to claim 1 or 2, wherein: having a pair of terminals, A distance between the protrusion formed on one end side of one of the terminals and the protrusion formed on one end side of the other of the terminals is smaller than an outer diameter of the coil.

7. The coil device according to claim 1, wherein: The protrusion functions as a connection portion of the terminal.

8. A coil device, comprising: A coil formed by winding a flat wire flat; a terminal having a holding surface at a connection portion for holding an end of a lead-out portion led out from the coil; and a magnetic core covering the wiring portion and the coil, The lead-out portion is led out along an imaginary line in contact with the outer circumference of the coil. The end of the lead portion is bent outward in a substantially L-shape along the imaginary line. The wiring portion clamps the end portion using a fixing piece and a bending piece. The holding surface is arranged on the fixing piece or the bending piece and extends substantially parallel to the winding axis of the coil. The fixing piece and the bent piece are arranged outside the imaginary line relative to a portion other than the end portion of the lead portion.

9. The coil device according to claim 8, wherein: The holding surface is opposite to a side surface of the magnetic core.

10. The coil device according to claim 8 or 9, wherein: When viewed from a direction perpendicular to the side surface of the magnetic core, the connection portion and the rest of the terminal excluding the connection portion are arranged to be offset in position.

11. The coil device according to claim 8 or 9, wherein: The terminal has a fixing portion disposed inside the magnetic core, An opening is formed in the fixing portion.

12. The coil device according to claim 8 or 9, wherein: The magnetic core includes magnetic particles and a resin binder.

13. The coil device according to claim 8 or 9, wherein: having a pair of terminals, The holding surface of one terminal and the holding surface of the other terminal face the same direction.

14. The coil device according to claim 8 or 9, wherein: having a pair of terminals, The connection portion of one of the terminals and the connection portion of the other terminal are arranged on a diagonal line with the coil interposed therebetween.

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