Inductor

Abstract

To provide a technology that can suppress the increase in mounting space in the height direction of the inductor, and that can achieve optimal positioning of the coil and base. [Solution] The inductor 1 comprises a coil 3, cores 33 and 39 positioned in the winding shaft hole 43 of the coil 3, and a base 9 that supports the coil 3. The coil 3 is joined to the base 9 by adhesive. The base 9 comprises a pair of lead outlet holes 21 and 23 through which the lead wires 17 and 19 at both ends of the coil 3 are inserted, and a pair of projections 25 and 27 that protrude from the upper surface 11 of the coil 3 along the coil 3 to restrict the tilt of the coil 3.

Description

Technical Field

[0006] , , , ,

[0007] ,

[0001] The present disclosure relates to an inductor used, for example, in a DC-DC converter or the like and a method for manufacturing the same.

Background Art

[0002] As an inductor, for example, an inductor having a bobbinless coil made of a flat copper wire, a magnetic core composed of an E-shaped core made of a magnetic material, and a pedestal having a lead-out hole is disclosed (see Patent Document 1).

[0003] In this prior art, as shown in FIG. 14A, the lead wire P1 of the coil is inserted into a lead-out hole P3 provided in the pedestal P2. Further, the tip of the lead wire P1 is exposed from the bottom surface of the pedestal P2, and this exposed tip is bent for positioning between the coil and the pedestal P2.

[0004] Then, as shown in FIG. 14B, the tip of the bent lead wire P1 is joined to the conductor pattern of the substrate P5 on which the inductor P4 is mounted by solder.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, when mounting the above-described inductor P4 on the substrate P5, the mounting space in the height direction increases by the thickness of the bent tip portion of the lead wire P1 and the amount of solder.

[0007] To address this issue of increased mounting space, as shown in Figure 14C, it is possible to adjust the length of the coil lead wires P1 and connect them by inserting the lead wires P1 exposed from the lead outlet holes P3 into through holes P6 formed in the substrate P5 without bending them. In this case, it is possible to suppress the increase in mounting space in the height direction of the inductor P4.

[0008] However, with this solution, the tip of the lead wire P1 is not bent, resulting in insufficient positioning between the coil and the base P2, and in some cases, there is a risk of the coil and core coming into contact. More specifically, one possible method for fixing the coil to the base P2 is to apply adhesive to the surface of the base P2 (i.e., the surface on which the coil will be placed), insert the coil's lead wires P1 through the lead outlet holes P3, and then allow the adhesive to harden.

[0009] However, the inner diameter of the lead outlet hole P3 is set slightly larger than the outer diameter of the lead wire P1 to facilitate insertion of the lead wire P1. Therefore, when the lead wire P1 is inserted into the lead outlet hole P3, the coil position is unstable until the adhesive hardens, making it difficult to position the coil. Specifically, it is difficult to keep the coil straight until the adhesive hardens, and the coil may tilt (i.e., tilt in the direction of the core axis).

[0010] Furthermore, if the coil tilts and comes into contact with the core, depending on the condition of the insulating coating on the coil's surface and the electrical characteristics of the core, electrical conductivity may be possible between the coil and the core. Moreover, if electrical conductivity is possible between the coil and the core, it will affect the characteristics of the inductor P4, and there is a risk that the coil current will leak to surrounding materials through the core.

[0011] Therefore, when fixing the coil to the base P2, it is desirable to suppress the tilting of the coil and position the coil in the appropriate position relative to the base P2. One aspect of this disclosure is to provide a technology that can suppress the increase in mounting space in the height direction of the inductor and achieve optimal positioning of the coil and the base. [Means for solving the problem]

[0012] One aspect of the present disclosure is an inductor comprising a coil, a core disposed in the winding shaft hole of the coil, and a base supporting the coil. In this inductor, the coil is bonded to the base with adhesive. The base also includes a pair of lead outlets through which the lead wires at both ends of the coil are inserted, and projections that extend from the surface supporting the coil along the coil, restricting the axial tilt of the coil's winding axis. [Effects of the Invention]

[0013] The configuration described above enables the inductor of this disclosure to suppress an increase in mounting space in the height direction and to achieve optimal positioning of the coil and base. [Brief explanation of the drawing]

[0014] [Figure 1] This is a perspective view showing the external appearance of the inductor according to the first embodiment. [Figure 2] This is an exploded perspective view showing the inductor of the first embodiment in disassembled form. [Figure 3] This is a perspective view showing a composite component in which a coil is mounted on a base according to the first embodiment. [Figure 4] This is a plan view showing a composite component of the first embodiment. [Figure 5] This is a front view showing a composite component of the first embodiment. [Figure 6] This is a bottom view showing a composite component of the first embodiment. [Figure 7] This is a right side view showing a composite component of the first embodiment. [Figure 8] This is a perspective view showing the base of the first embodiment. [Figure 9] Figure 9A is a plan view showing the base of the first embodiment, Figure 9B is a front view showing the base, Figure 9C is a bottom view showing the base, and Figure 9D is a right side view showing the base. [Figure 10]It is an explanatory diagram showing a method of manufacturing an inductor according to the first embodiment. [Figure 11] It is an exploded perspective view showing the inductor according to the second embodiment disassembled. [Figure 12] FIG. 12A is a plan view showing the pedestal according to the third embodiment, FIG. 12B is a front view showing the pedestal according to the third embodiment, FIG. 12C is a plan view showing the pedestal according to the fourth embodiment, and FIG. 12D is a front view showing the pedestal according to the fourth embodiment. [Figure 13] FIG. 13A is a plan view showing the pedestal according to the fifth embodiment, FIG. 13B is a front view showing the pedestal according to the fifth embodiment, FIG. 13C is a plan view showing the pedestal according to the sixth embodiment, and FIG. 13D is a front view showing the pedestal according to the sixth embodiment. [Figure 14] FIG. 14A is a perspective view showing the bottom side of a conventional inductor, FIG. 14B is an explanatory diagram showing the mounting state of the conventional inductor on a substrate, and FIG. 14C is an explanatory diagram showing the mounting state of the inductor on a substrate when the lead wire is not bent.

Embodiments for Carrying Out the Invention

[0015] Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the drawings. [1. First Embodiment] [1-1. Configuration] As shown in FIG. 1, the inductor 1 according to the first embodiment includes a coil 3, a pair of core members 5 and 7 disposed in the vicinity of the coil 3, and a pedestal 9 that supports (i.e., fixes) the coil 3. <00001​​​​​​Furthermore, in a plan view from the Y-axis direction, the line passing through the centroid of inductor 1 is defined as the OY line, the axis of the winding shaft as the OZ line, and the line passing through the intersection of the OY and OZ lines and perpendicular to both lines as the OX line. Note that the OY line, OZ line, and OX line correspond to the Y-axis, Z-axis, and X-axis, respectively.

[0018] As shown in Figure 2, the coil 3 is positioned on the surface (i.e., top surface) 11 of the base 9 of the inductor 1 such that the winding axis of the coil 3 is in the Z-axis direction. In other words, the winding portion 13 of the coil 3 is placed on the top surface 11 of the base 9 along the XY plane. The winding axis is the same as the OZ line and is the axial center of the winding portion 13.

[0019] In this inductor 1, a pair of core members 5 and 7 are arranged parallel to the XY plane and facing each other, sandwiching the coil 3 from both sides in the thickness direction (Z-axis direction). Note that the inductor 1 is point-symmetric in a plan view from the Y-axis direction.

[0020] As will be described in detail later, as shown in Figures 3 to 7, the winding portion 13 of the coil 3 is placed in the recess 15 on the upper surface 11 of the base 9 and fixed to the base 9 with adhesive (see Figure 3). In addition, the pair of lead wires 17 and 19 of the coil 3 (see Figure 5) are inserted through the pair of lead outlet holes 21 and 23 of the base 9 (see Figures 4 and 6).

[0021] Furthermore, the base 9 is provided with a pair of protrusions 25 and 27 (see Figures 4 and 7) on both sides of the winding portion 13 of the coil 3 in the Z-axis direction, which restrict the tilt of the coil 3. The following provides a detailed explanation of each component.

[0022] [1-2. Composition of each part] <coil> As shown in Figure 2, the coil 3 comprises a winding section 13 in which wire is wound in an annular shape around a winding axis, and a pair of lead wires 17 and 19 (i.e., a first lead wire 17 and a second lead wire 19) extending from both ends of the winding section 13. The winding axis is the axis around which the wire is wound.

[0023] Specifically, the winding portion 13 of the coil 3 has a ring shape when viewed along the winding axis (i.e., when viewed from the front in the Z-axis direction), and lead wires 17 and 19 extend from both the left and right ends of the ring in the direction of the base 9 (i.e., downwards).

[0024] In the first embodiment, the coil 3 is an edgewise coil formed by winding a rectangular conductor, which is a wire, around a winding axis with the wider surface of the rectangular conductor perpendicular to the winding axis.

[0025] Furthermore, the surface of coil 3 (i.e., the surface of the rectangular conductor) is covered with an electrical insulating material, as is well known. However, the surfaces of the pair of lead wires 17 and 19 of coil 3 are not covered with an electrical insulating material, and are instead plated with solder, as will be described later. For example, copper can be used as the material for the conductor portion of coil 3.

[0026] The dimensions of the winding portion 13 of coil 3 are, for example, an inner diameter of 12.8 mm and an outer diameter of 20.8 mm. The overall height (Y-axis dimension) of coil 3, including each lead wire 17 and 19, is, for example, 24.4 mm, and the thickness (Z-axis dimension) is, for example, 5.7 mm.

[0027] <Core component> As the material for each core member 5, 7 (i.e., the first core member 5 and the second core member 7), known materials such as Ni-Zn ferrite used in the inductor 1 can be employed. In addition, other materials such as Mn-Zn ferrite can also be employed.

[0028] As shown in Figure 2, each core member 5 and 7 has the same shape, which is approximately E-shaped when viewed from the Y-axis direction (shape in plan view). More specifically, the first core member 5 comprises an outer wall portion 31, a first core 33, and a pair of leg portions 35a and 35b. The outer wall portion 31 is a rectangular plate-shaped member arranged along the XY plane. The first core 33 is a cylindrical member positioned at the center (center of gravity) of the outer wall portion 31 as viewed from the Z-axis direction, and projecting inward (i.e., to the rear) along the Z-axis direction. The pair of leg portions 35a and 35b are members that project inward along the Z-axis direction from both the left and right ends (both ends in the X-axis direction) of the outer wall portion 31, similar to the first core 33.

[0029] Similarly, the second core member 7 comprises an outer wall portion 37, a second core 39, and a pair of legs 41a and 41b. The outer wall portion 37 is a rectangular plate-shaped member arranged along the XY plane. The second core 39 is a cylindrical member positioned at the center of gravity of the outer wall portion 37 as viewed from the Z-axis direction, and projecting inward (i.e., forward) along the Z-axis direction. The pair of legs 41a and 41b are members that project inward along the Z-axis direction from both the left and right ends of the outer wall portion 37, similar to the second core 39.

[0030] Note that the length (dimension) of the portion that protrudes in the Z-axis direction from each core 33, 39 and each leg portion 35a, 35b, 41a, 41b is the same. Each core 33, 39 has a circular outer surface. Each core 33, 39 is positioned along the inner circumference of the winding shaft hole 43, maintaining a distance from the coil 3. The winding shaft hole 43 is a through hole that penetrates the center of the winding portion 13 in the Z-axis direction when viewed from the front.

[0031] Furthermore, each leg portion 35a, 35b, 41a, and 41b has an arc-shaped inner circumferential surface. Each leg portion 35a, 35b, 41a, and 41b is positioned along the outer circumference of the annular shape of the winding portion 13 of the coil 3, maintaining a distance from the coil 3.

[0032] Furthermore, the two core members 5 and 7 are positioned opposite each other so as to sandwich the winding portion 13 of the coil 3 from both sides in the axial direction of the winding axis. In other words, the two core members 5 and 7 are positioned symmetrically with respect to the coil 3, with the inner sides of the respective cores 33 and 39 facing each other.

[0033] Each core member 5 and 7 is positioned facing each other, so that the tips of each core 33 and 39 come into contact with each other. In this configuration, each core 33 and 39 functions as a single core positioned along the winding axis of the coil 3. Alternatively, the ends of core 33 and core 39 may not be in contact, and a predetermined gap may be provided between them. For example, the length (dimension) of the portion of each core 33 and 39 that protrudes in the Z-axis direction may be shorter than the length of the portion of each leg 35a, 35b, 41a, and 41b that protrudes in the Z-axis direction. Providing such a predetermined gap has the advantage of suppressing magnetic saturation.

[0034] Furthermore, the pair of legs 35a and 35b of the first core member 5 are positioned facing the pair of legs 41a and 41b of the second core member 7, and their respective ends are joined together with adhesive. In other words, the pair of core members 5 and 7 are integrally joined together with adhesive.

[0035] Furthermore, there are gaps between the pair of legs 35a and 35b of the first core member 5 and between the pair of legs 41a and 41b of the second core member 7. Therefore, when the pair of core members 5 and 7 are integrated, a space 44 (see Figure 1) is formed above the inductor 1 in which the upper part of the coil 3 is exposed.

[0036] <Base> As shown in Figures 8 and 9, the base 9 is a roughly rectangular parallelepiped-shaped member and is made of an electrically insulating resin such as polybutylene terephthalate (i.e., PBT). Other resins, such as polyethylene terephthalate (i.e., PET), may also be used.

[0037] On the surface (i.e., the upper surface) 11 of the base 9, planar flat sections 46a and 46b are provided on both sides in the X-axis direction. Furthermore, the recess 15 is provided in the central part between the two flat sections 46a and 46b.

[0038] As shown in Figure 9B, the recess 15, when viewed from the Z-axis direction, is curved in an arc shape, similar to the outer shape of the winding portion 13. Furthermore, as shown in Figure 9A, the recess 15 has a support recess 45 in its central part in the Z-axis direction, on which the lower part of the winding portion 13 of the coil 3 is seated. The recess 15 also has side recesses 47a and 47b on the outer side (i.e., the front and rear sides) of the central part. The support recess 45 and the side recesses 47a and 47b are approximately rectangular in plan view.

[0039] Furthermore, the base 9 is provided with a first lead outlet hole 21 and a second lead outlet hole 23 that penetrate the base 9 in the Y-axis direction. The first lead outlet hole 21 is a through hole through which the first lead wire 17 is inserted, and the second lead outlet hole 23 is a through hole through which the second lead wire 19 is inserted.

[0040] The shapes of the first lead outlet hole 21 and the second lead outlet hole 23 are rectangular in plan view, similar to the external shapes of the first lead wire 17 and the second lead wire 19. In other words, the first lead outlet hole 21 and the second lead outlet hole 23 are through holes with a rectangular parallelepiped space.

[0041] More specifically, as shown in Figure 9A, the first lead outlet hole 21 is provided in front of the support recess 45 and adjacent to the support recess 45. In other words, the first lead outlet hole 21 is provided in front of the OX line, to the right of the center of the base 9 in the X-axis direction, and parallel to the OX line.

[0042] Furthermore, the second lead outlet hole 22 is provided on the rear side of the support recess 45, adjacent to the support recess 45. In other words, the second lead outlet hole 22 is provided on the left side of the center of the base 9, parallel to the OX line, behind the OX line.

[0043] The first lead outlet hole 21 and the second lead outlet hole 23 are point-symmetric in plan view. Point G in Figure 9A is the center of point symmetry (i.e., the centroid of the base 9 in plan view). The first lead outlet hole 21 and the second lead outlet hole 23 are positioned at a predetermined distance α in the Z-axis direction and at a predetermined distance β in the X-axis direction.

[0044] Furthermore, as shown in Figure 8, a pair of protrusions 25 and 27 (i.e., a first protrusion 25 and a second protrusion 27) are provided on the upper surface 11 of the base 9. These pair of protrusions 25 and 27 are flat and are provided parallel to each other so as to protrude upward from the upper surface 11.

[0045] More specifically, as shown in Figure 9A, the first projection 25 is located in front of the OX line, adjacent to the front of the support recess 45 and the left side of the first lead outlet hole 21, and is provided parallel to the OX line. The left end of the first projection 25 extends to approximately the same position as the left end of the opposing second lead outlet hole 23. In the Z-axis direction, the dimension (thickness) of the first projection 25 is larger than the dimension of the first lead outlet hole 21.

[0046] Furthermore, the second projection 27 is located behind the OX line, adjacent to the rear of the support recess 45 and to the right of the second lead outlet hole 23, and is provided parallel to the OX line. The right end of the second projection 27 extends to approximately the same position as the right end of the opposing first lead outlet hole 21. In the Z-axis direction, the dimension (thickness) of the second projection 27 is greater than the dimension of the second lead outlet hole 21.

[0047] In other words, the two protrusions 25 and 27 are positioned to sandwich the support recess 45 (and therefore the winding portion 13 of the coil 3) from both sides in the Z-axis direction. The heights of the two protrusions 25 and 27 will be described in detail later.

[0048] Furthermore, as shown in Figures 8 and 9A, the base 9 is provided with end projections 49a and 49b that protrude upward from the flat portions 46a and 46b at both ends of the support recess 45 in the X-axis direction. The height (ΔH1: see Figure 9B) of these end projections 49a and 49b is, for example, 1.0 mm or more.

[0049] Furthermore, as shown in Figure 9C, the back surface 51 of the base 9 (i.e., the surface opposite to the top surface 11) has a planar shape. At the four corners of this back surface 51, there are bottom protrusions 53 with a predetermined thickness that protrude downwards. The thickness of the bottom protrusions 53 (the dimension that protrudes in the Y-axis direction) can be, for example, 0.5 mm or more.

[0050] Next, the configuration in which the coil 3 is attached to the base 9 (i.e., the composite component 55) will be explained in detail based on Figures 4 to 7.

[0051] As shown in Figures 4 and 5, the coil 3 has its lead wires 17 and 19 fitted into the lead outlet holes 21 and 23, and the wound portion 13 of the coil 3 is seated in the recess 15 (more specifically, the support recess 45). The coil 3 and the base 9 are joined by an adhesive applied to the surface of the support recess 45.

[0052] Furthermore, as described above (see Figures 4 and 7), the first projection 25 is positioned adjacent to one outer side (front side) of the winding portion 13 of the coil 3 and protrudes upward. The inner surface (rear side) of the first projection 25 and one outer surface (front side) of the winding portion 13 are parallel with a small gap between them when the coil 3 is not tilted. This gap can be, for example, in the range of 0.05 mm to 0.2 mm.

[0053] Therefore, as will be described later, when the coil 3 is joined with adhesive, the first projection 25 functions to restrict the forward tilt of the coil 3. Similarly, the second projection 27 is positioned along the other outer (rear) side of the winding portion 13 of the coil 3 and protrudes upward. The inner surface (front surface) of the second projection 29 and the other outer surface (rear surface) of the winding portion 13 are parallel with a small gap between them when the coil 3 is not tilted. This gap can be, for example, in the range of 0.05 mm to 0.2 mm.

[0054] Therefore, as will be described later, when the coil 3 is joined with adhesive, the second projection 27 functions to restrict the tilting of the coil 3 toward the rear. In other words, the pair of protrusions 25 and 27 are positioned to sandwich the coil 3 (more specifically, the winding portion 13) from both sides in the axial direction. This makes it possible to suppress any tilting of the coil 3 in either direction in the axial direction.

[0055] Furthermore, as shown in Figure 5, the heights of both protrusions 25 and 27 are set lower than the lower ends of the pair of cores 33 and 39 so as not to come into contact with them. Specifically, for example, they are set lower than the lower end of the inner circumferential surface of the winding portion 13.

[0056] Furthermore, the heights of both protrusions 25 and 27 are set so that the coil 3 does not tilt beyond a predetermined value (for example, 5° or more). Therefore, in the inductor 1 of this first embodiment, the tilt of the coil 3 is less than 5° with respect to the XY plane. Similarly, in other embodiments described later, the tilt of the coil 3 is also less than 5°.

[0057] Specifically, the upper ends of both protrusions 25 and 27 are set to be higher by a predetermined value ΔH2 than the flat portions 46a and 46b of the upper surface 11 of the base 9. Furthermore, the upper ends of both protrusions 25 and 27 are set to be higher by ΔH3 from the bottom (i.e., the lower end) of the recess 15 (more specifically, the support recess 45).

[0058] For example, ΔH2 can be set in the range of 1.5 mm to 4.0 mm, and for example, ΔH3 can be set in the range of 1.5 mm to 5.0 mm. Note that ΔH2 will vary depending on ΔH3, and if the support recess 45 is not provided, ΔH2 = ΔH3. In the case of a rectangular conductor, ΔH3 is determined by the width of the rectangular conductor (the radial dimension of coil 3). Therefore, in this first embodiment, ΔH3 is in the range of 0.4 times or more and 0.6 times or less the width of the rectangular conductor.

[0059] Furthermore, each lead wire 17 and 19 protrudes from the respective lead outlet holes 21 and 23 on the back surface 51 of the base 9, and the length of the protruding exposed wire can be set to 3.5 mm or more and 4.5 mm or less.

[0060] Furthermore, the difference between the thickness of one coil 3 (i.e., the thickness of each lead wire 17, 19) and the width of each lead outlet hole 21, 23 (the difference in the dimension in the Y-axis direction) can be, for example, 0.1 mm or more and 0.4 mm or less.

[0061] [1-3. Manufacturing Procedure] Next, the manufacturing method of the inductor 1 of this first embodiment will be described with reference to Figure 10.

[0062] (1) The coil 3 (i.e., the edgewise coil) is formed into the shape shown in Figure 10. (2) The insulating coating on both ends of coil 3 is stripped off by laser to form the two lead wires 17 and 19.

[0063] (3) The surfaces of lead wires 17 and 19 are plated with solder. (4) Apply an adhesive (for example, an epoxy adhesive) to the surface of the base 9 where the coil 3 is fixed (i.e., the support recess 45).

[0064] (5) Insert each lead wire 17, 19 of the coil 3 into each lead outlet hole 21, 23 of the base 9. At this time, since both protrusions 25, 27 are located along both sides in the thickness direction of the winding portion 13 of the coil 3, the winding portion 13 of the coil 3 moves along both protrusions 25, 27. Then, the lower part of the winding portion 13 of the coil 3 sits in the support recess 45 of the base 9, and adhesive adheres to the lower part of the winding portion 13 and between the winding portion 13 and both protrusions 25, 27.

[0065] (6) Apply adhesive (for example, epoxy adhesive) to the tips of the legs 35a, 35b, 41a, and 41b of the pair of core members 5 and 7. Alternatively, the adhesive may be applied to only one of the core members. For example, apply the adhesive to the tips of the core members within the range of the dashed lines R1 and R2.

[0066] (7) Apply adhesive (e.g., epoxy adhesive) to the top of each core 33, 39 of the pair of core members 5, 7. Alternatively, the adhesive may be applied to only one of the cores. For example, apply the adhesive to the top of the core within the range of the dashed line R3.

[0067] (8) A pair of core members 5 and 7 are placed on both sides (front and back) of the coil 3 in the thickness direction, so as to sandwich the coil 3. (9) The components are set in a jig that determines the relative positions of each component, and then placed in a drying oven to dry (harden) the adhesive, thereby completing the inductor 1.

[0068] When fixing the inductor 1 manufactured in this manner to the circuit board, the following procedure is followed (not shown). The inductor 1 is placed on the circuit board, and the lead wires 17 and 19 protruding from the back surface 51 of the base 9 are inserted into the through-holes of the circuit board. Then, the coil 3 (and therefore the inductor 1) is fixed to the circuit board (i.e., mounted) by soldering the surface of the lead wires 17 and 19.

[0069] [1-4. Effects] Next, the effects of this first embodiment will be described. (1) In this first embodiment, the base 9 includes lead outlet holes 21, 23 through which each lead wire 17, 19 of the coil 3 is inserted, and a pair of projections 25, 27 that protrude from the upper surface 11 of the coil 3 along the coil 3 and restrict the tilt of the coil 3.

[0070] More specifically, the device includes a first projection 25 that restricts the tilt of the coil 3 to one side in the axial direction of the winding shaft, and a second projection 27 that restricts the tilt of the coil 3 to the other side. Furthermore, the tips of the lead wires 17 and 19 protruding from the lead outlet holes 21 and 23 are shaped to protrude in a straight line along the insertion direction of each lead outlet hole 21 and 23.

[0071] This allows the inductor 1 to suppress an increase in mounting space in the height direction, and enables optimal positioning of the coil 3 and the base 9. In other words, in this inductor 1, the ends of the lead wires 17 and 19 are straight, so the lead wires 17 and 19 can be inserted into through-holes and fixed to the circuit board. This helps to suppress the increase in mounting space in the height direction.

[0072] Furthermore, as described above, since a pair of protrusions 25 and 27 are provided, when fixing the coil 3 to the base 9 with adhesive, tilting of the coil 3 can be suppressed until the adhesive hardens. In other words, tilting of the coil 3 to both sides in the axial direction can be suppressed. As a result, various problems that occur when the coil 3 tilts and comes into contact with each core 33 and 39 (for example, a decrease in the performance of the inductor 1 or leakage current) can be suppressed.

[0073] (2) In this first embodiment, both projections 25 and 27 are positioned to sandwich the winding portion 13 of the coil 3 from both sides in the axial direction of the winding shaft. This effectively suppresses tilting of the coil 3 to both sides.

[0074] (3) In this first embodiment, the height ΔH3 of both projections 25 and 27 from the upper surface 11 of the base 9 is 1.5 mm or more and 5.0 mm or less. With these dimensions, the tilt of the coil 3 can be effectively suppressed.

[0075] (4) In this first embodiment, the difference between the thickness of each lead wire 17, 19 and the width of each lead outlet hole 21, 23 in the axial direction is 0.1 mm or more and 0.4 mm or less, respectively. In other words, because of this dimensional difference, each lead wire 17, 19 can be easily inserted into each lead outlet hole 21, 23. Furthermore, even if each lead wire 17, 19 (and therefore the coil 3) is tilted due to this dimensional difference, the tilt of the coil 3 can be suitably suppressed by the above configuration.

[0076] (5) In this first embodiment, the upper surface 11 of the base 9 is provided with a curved support recess 45. This makes it easier to determine the position of the coil 3, so that the base 9 can suitably support the coil 3. In addition, by having the coil 3 seated in the support recess 45, the height dimension of the inductor 1 can be reduced.

[0077] (6) In this first embodiment, the support recess 45 is provided with end protrusions 49a and 49b that project from the upper surface 11 of the base 9 at both ends (left and right ends) in the X-axis direction. This makes it possible to suppress tilting (i.e., rotation) of the coil 3 in the left and right directions.

[0078] (7) In this first embodiment, the base 9 is provided with a plurality of bottom protrusions 53 on the back surface 51 side which function as spacers. This allows gas generated when soldering the lead wires 17 and 19 to the substrate to escape easily, thereby suppressing defects in solder joints caused by gas.

[0079] (8) In this first embodiment, a space 44, which is a through hole through which the upper part of the coil 3 is exposed, is provided at the upper part of the portion where the pair of core members 5 and 7 are combined, which has the advantage that the heat generated inside the inductor 1 can be efficiently released to the outside.

[0080] (9) In this first embodiment, the method for manufacturing the inductor 1 includes the steps of: applying adhesive to the surface of the base 9 on which the coil 3 is supported; inserting each lead wire 17, 19 of the coil 3 into the respective lead outlet holes 21, 23 and placing the coil 3 on the surface of the base 9; and restricting the tilt of the coil 3 with a pair of protrusions 25, 27 until the adhesive hardens.

[0081] This configuration suppresses the tilt of the coil 3 during the manufacturing of the inductor 1, thereby preventing various problems caused by the coil 3 contacting each of the cores 33 and 39. [2. Second Embodiment] Since the basic configuration of the second embodiment is the same as that of the first embodiment, the differences from the first embodiment will be described below. Reference numerals that are the same as those in the first embodiment indicate the same components, and refer to the preceding description.

[0082] This second embodiment differs from the first embodiment mainly in its protrusions. As shown in Figure 11, the inductor 61 of this second embodiment comprises a coil 3, a pair of core members 5 and 7, and a base 63. The coil 3 and the pair of core members 5 and 7 are the same as those in the first embodiment.

[0083] In this second embodiment, the base 63 is point-symmetrical in a plan view from the Y-axis direction. The base 63 has a pair of flat plate-shaped protrusions 65 and 67 on either side of the support recess 45, in substantially the same positions as in the first embodiment. However, the width (dimension) of both protrusions 65 and 67 in the left-right direction (X-axis direction) is set to be shorter than in the first embodiment.

[0084] The two protrusions 65 and 67 are located between the left and right lead wires 17 and 19 in the X-axis direction. This second embodiment provides the same effects as the first embodiment.

[0085] [3. Third to Sixth Embodiments] Since the basic configuration of the third to sixth embodiments is the same as that of the first embodiment, the following will mainly describe the differences from the first embodiment. Note that the same reference numerals as in the first embodiment indicate the same components, and refer to the preceding description.

[0086] <Third Embodiment> As shown in Figures 12A and 12B, the base 71 of the inductor in the third embodiment is provided with both protrusions 73 and 75 in positions different from those in the first embodiment.

[0087] Specifically, in a plan view from the Y-axis direction, the first projection 73 is positioned in front of the first lead outlet hole 21 and along the first lead outlet hole 21. The second projection 75 is positioned behind the second lead outlet hole 23 and along the second lead outlet hole 23.

[0088] In other words, the first projection 73 is positioned along the first lead wire 17 on one outer side (front side) of the first lead wire 17. This restricts the forward tilt of the coil 3. The second projection 75 is positioned along the second lead wire 19 on the other outer side (rear side) of the second lead wire 19, and this restricts the rearward tilt of the coil 3.

[0089] This third embodiment provides the same effects as the first embodiment. <Fourth Embodiment> As shown in Figures 12C and 12D, the base 81 of the inductor in the fourth embodiment has a different shape of projection than that of the third embodiment.

[0090] Specifically, the first projection 83 is L-shaped in a plan view from the Y-axis direction. This first projection 83 is positioned along the first lead outlet hole 21 so as to surround the front and right sides of the first lead outlet hole 21. The second projection 85 is also L-shaped in a plan view. This second projection 85 is positioned along the second lead outlet hole 23 so as to surround the rear and left sides of the second lead outlet hole 23.

[0091] This fourth embodiment provides the same effects as the third embodiment. Furthermore, it can also restrict the tilt of coil 3 in the left-right direction (X-axis direction). <Fifth Embodiment> As shown in Figures 13A and 13B, the base 91 of the inductor in the fifth embodiment is provided with two protrusions 93 and 95 that combine the shape of a protrusion like that of the first embodiment and a protrusion like that of the third embodiment.

[0092] Specifically, in a plan view from the Y-axis direction, the first projection 93 is continuously arranged along the front side of the support recess 45 and the front side of the first lead outlet hole 21. The second projection 95 is continuously arranged along the rear side of the support recess 47 and the rear side of the second lead outlet hole 23.

[0093] This fifth embodiment provides the same effects as the first embodiment. <Sixth Embodiment> As shown in Figures 13C and 13D, the base 101 of the inductor in the sixth embodiment is provided with projections 103, 105, 107, and 109, which are arranged separately in the X-axis direction, and which are similar to the projections in the first embodiment and the projections in the third embodiment.

[0094] Specifically, in a plan view from the Y-axis direction, first projections 103 and 105 are provided in front of the OX line, along the left-right direction. Second projections 107 and 109 are provided behind the OX line, also along the left-right direction.

[0095] More specifically, in front of the OX line, the left first projection 103 is positioned along the front side of the support recess 45, and the right first projection 105 is positioned along the front side of the first lead outlet hole 21. Furthermore, in rear of the OX line, the right second projection 109 is positioned along the rear side of the support recess 45, and the left second projection 107 is positioned along the rear side of the second lead outlet hole 23.

[0096] This sixth embodiment provides the same effects as the fifth embodiment. [4. Other Embodiments] While embodiments of this disclosure have been described above, it goes without saying that this disclosure is not limited to the embodiments described above and can take various forms.

[0097] (4a) The protrusions only need to be able to restrict the tilt of the coil when fixing the coil with adhesive, for example, and there are no particular restrictions on their shape or arrangement within the scope of this disclosure. (4b) In the above embodiment, a flat plate-shaped member was used as the projection, but other shapes are also acceptable as long as they can restrict the inclination of the coil. For example, a rod-shaped member such as a cylinder or a rectangular prism may be used. Alternatively, the tip of the projection may be bent toward the coil, forming an inverted L-shape.

[0098] (4c) The number of protrusions is not particularly limited, as long as it can regulate the inclination of the coil. (4d) In the above embodiment, a gap is provided between the coil and the projection for the adhesive to be introduced, but the coil and the projection may be in contact. (4e) In addition to rectangular conductors, wires of various known shapes can be used as the wires that make up the coil.

[0099] (4f) Multiple functions of one component in each of the above embodiments may be realized by multiple components, or one function of one component may be realized by multiple components. Also, multiple functions of multiple components may be realized by one component, or one function realized by multiple components may be realized by one component. Furthermore, some of the configurations of each of the above embodiments may be omitted. Furthermore, at least some of the configurations of each of the above embodiments may be added to or replaced with the configurations of other embodiments. [Explanation of Symbols]

[0100] 1, 61...Inductor, 3...Coil, 5, 7...Core component, 9, 63, 71, 81, 91, 101...Base, 13...Winding section, 17, 19...Lead wire, 21, 23...Lead outlet hole, 25, 27, 65, 67, 73, 75, 83, 85, 93, 95, 103, 105, 107, 109...Protrusion, 33, 39...Core, 45...Support recess, 43...Winding shaft hole, 51...End protrusion, 53...Bottom protrusion,

Claims

1. A coil, a core positioned in the winding shaft hole of the coil, and a base supporting the coil, In addition to being equipped, The base comprises a pair of lead outlet holes through which the lead wires at both ends of the coil are inserted, and projections that extend from the surface supporting the coil along the winding portion formed by the winding of the coil and along the lead wires, thereby restricting the axial tilt of the winding axis of the coil. The projection comprises a first projection positioned on one side of the coil in the axial direction to restrict tilting to that side, and a second projection positioned on the other side of the coil to restrict tilting to that side. Inductor.

2. An inductor according to claim 1, An inductor in which the distance between the lead wires is smaller than the inner diameter of the winding shaft hole of the coil.

3. An inductor according to claim 2, The coil is an edgewise coil formed by winding the wide surface of a rectangular conductor perpendicular to the winding axis, and is an inductor.

4. An inductor according to claim 2, An inductor in which the height of the projection from the surface of the base is 1.5 mm or more and 5.0 mm or less.

5. An inductor according to any one of claims 2 to 4, An inductor in which, in the axial direction, the difference between the thickness of the lead wire and the width of the lead outlet hole is 0.1 mm or more and 0.4 mm or less.

6. An inductor according to any one of claims 2 to 5, An inductor in which the length of the tip of the lead wire protruding from the lead outlet hole is 3.5 mm or more and 4.5 mm or less.

7. An inductor according to any one of claims 2 to 6, An inductor wherein the surface of the base has a support recess that is curved according to the outer shape of the winding portion, on which the coil is wound, is seated.

8. An inductor according to any one of claims 2 to 7, In the direction in which each of the lead guide holes, which are perpendicular to the axial direction, is arranged, the end of the portion on which the winding portion around which the coil is wound is seated is provided with an end projection that protrudes from the surface of the base and restricts the rotation of the coil.

9. An inductor according to any one of claims 2 to 8, An inductor having a plurality of bottom protrusions on the back side of the base opposite to the front side, which protrudes in the opposite direction to the front side.

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