Coil component and filter circuit

Abstract

A coil component (1) according to the present disclosure comprises a housing (4), a coil (L1), and a coil (L2). The housing (4) has, on at least one surface thereof, a protrusion (4c) that is close to a portion of lead wires (2b, 2d, 3b, 3d). The protrusion (4c) and the lead wires (2b, 2d, 3b, 3d) are disposed facing each other in a region close to each other, and are disposed so as to overlap each other when viewed from any of the directions perpendicular to the direction in which the protrusion (4c) protrudes.

Description

Coil components and filter circuits

[0001] The present disclosure relates to a coil component and a filter circuit that implements the coil component.

[0002] Conventionally, there have been coil components in which a coil is formed by bending a metal plate. Japanese Patent Laid-Open Publication No. 2004-296630 (Patent Document 1) discloses, as an example of a coil component, a coil component having four terminals extending outward from a main body portion.

[0003] Japanese Patent Application Laid-Open No. 2004-296630

[0004] The coil and the terminals (also referred to as lead wires) extending from the coil are made of a relatively soft metal, such as copper, that has low electrical resistance. Therefore, when an external force is applied to the coil component, the lead wires may be deformed by the external force, causing a change in inductance. For example, when the coil component is used in a filter circuit, a change in inductance may affect the function of the filter circuit. The coil component disclosed in Patent Document 1 does not take into consideration the effects of external forces.

[0005] Therefore, an object of the present disclosure is to provide a coil component that prevents deformation of the lead wire, and a filter circuit in which the coil component is mounted.

[0006] A coil component according to one embodiment of the present disclosure includes a housing having a pair of opposing first and second main surfaces and four side surfaces connecting the first and second main surfaces, a first coil section disposed inside the housing, a first coil conductor having a first lead wire and a second lead wire drawn from the first coil section, a second coil section disposed inside the housing and having an opening at least partially overlapping with the opening of the first coil section, and a second coil conductor having a third lead wire and a fourth lead wire drawn from the second coil section. The first lead wire is drawn from the first side surface of the housing and extends to the second main surface. The second lead wire is drawn from the first side surface of the housing and extends to the second main surface. The third lead wire is drawn from the second side surface of the housing and extends to the second main surface. The fourth lead wire is drawn from the second side surface of the housing and extends to the second main surface. The housing has, on at least one surface, a protrusion adjacent to a portion of the first, second, third, and fourth draw-out lines, and the protrusion and the first, second, third, and fourth draw-out lines are arranged opposite each other in the adjacent region and overlap each other when viewed from any direction perpendicular to the direction in which the protrusions protrude.

[0007] A filter circuit according to an embodiment of the present disclosure includes the above-described coil component and a capacitor connected to the coil component.

[0008] According to one embodiment of the present disclosure, the protrusion and the first, second, third, and fourth lead wires are arranged to face each other in a nearby region and to overlap in the direction in which the protrusion protrudes, so that when an external force is applied to the housing, the lead wires are supported by the protrusion, thereby preventing deformation of the lead wires.

[0009] 1 is a perspective view of a coil component according to a first embodiment; a front view of the coil component according to the first embodiment; a right side view of the coil component according to the first embodiment; a bottom view of the coil component according to the first embodiment; a circuit diagram of a filter circuit including the coil component according to the first embodiment; a perspective view of a coil component according to a second embodiment; a front view of the coil component according to the second embodiment; a rear view of the coil component according to the second embodiment; a right side view of the coil component according to the second embodiment; a left side view of the coil component according to the second embodiment; a plan view of the coil component according to the second embodiment; a bottom view of the coil component according to the second embodiment; a cross-sectional view taken along line 3H-3H in the plan view of the coil component according to the second embodiment; a perspective view of a coil component according to a third embodiment; a front view of the coil component according to the third embodiment; a right side view of the coil component according to the third embodiment; a bottom view of the coil component according to the third embodiment; a perspective view of a coil component according to a fourth embodiment; a front view of the coil component according to the fourth embodiment; a right side view of the coil component according to the fourth embodiment; a bottom view of the coil component according to the fourth embodiment; a right side view of the coil component according to the fourth embodiment; a right side view of the coil component according to the fourth embodiment; a right side view of the coil component according to the fourth embodiment; a right side view of the coil component according to the fourth embodiment; Fig. 10 is a bottom view of a coil component according to a modified example of embodiment 4. Fig. 11 is a perspective view of a coil component according to embodiment 5. Fig. 12 is a front view of a coil component according to embodiment 5. Fig. 13 is a right side view of a coil component according to embodiment 5. Fig. 14 is a bottom view of a coil component according to embodiment 5.

[0010] <First Embodiment> A coil component according to the first embodiment will be described below. Fig. 1A is a perspective view of the coil component 1 according to the first embodiment. Fig. 1B is a front view of the coil component 1 according to the first embodiment. Fig. 1C is a right side view of the coil component 1 according to the first embodiment. Fig. 1D is a bottom view of the coil component 1 according to the first embodiment. Fig. 2 is a circuit diagram of a filter circuit 100 including the coil component 1 according to the first embodiment. When the X-axis, Y-axis, and Z-axis are defined as shown in Figs. 1A to 1D, the X-axis direction is the left-right direction of the coil component 1, the Y-axis direction is the front-rear direction of the coil component 1, and the Z-axis direction is the up-down direction of the coil component 1.

[0011] The coil component 1 is, for example, a transformer coil mounted in a filter circuit 100 used to reduce noise in a power line. As will be described later, the coil component 1 magnetically couples two coils to cancel the parasitic inductance of a capacitor mounted in the filter circuit.

[0012] The coil component 1 includes a housing 4, a coil portion 2a (first coil) having a rectangular opening, and a coil portion 3a (second coil) having a rectangular opening. Hereinafter, the coil portion 2a will also be referred to as coil L1, and the coil portion 3a will also be referred to as coil L2. The coils L1 and L2 are conductors formed from metal plates, such as copper or an alloy of copper and other metals. The main component of the coils L1 and L2 is copper, with the copper content being at least 50% or more, preferably 80% or more.

[0013] The coils L1 and L2, which are formed from metal plates, are covered with an insulating material (not shown). Specifically, the insulating material covering the coils L1 and L2 is a resin such as polyimide or epoxy. Note that the insulating material does not need to cover all surfaces of the coils L1 and L2. To prevent contact between the coils L1 and L2, it is sufficient that the insulating material is provided at least on the surfaces where the coils L1 and L2 face each other. Furthermore, although a single-turn coil is illustrated in the present disclosure, a multiple-turn coil may also be used.

[0014] The housing 4 has a pair of opposing first and second main surfaces, a flat surface 41 and a bottom surface 42, respectively, and four side surfaces connecting the flat surface 41 and the bottom surface 42: a right side surface 43 (second side surface), a left side surface 44 (first side surface), a front surface 45 (fourth side surface), and a back surface 46 (third side surface). Each side is one surface when the housing 4 is viewed as a substantially rectangular parallelepiped, and does not necessarily have to be flat, and each surface may have irregularities. The housing 4 is made of a molded resin for fixing the coils L1 and L2. Specifically, the molded resin is made of one of epoxy resin with silica filler added, silicone resin, liquid crystal polymer, or various resins containing a metal magnetic material.

[0015] The coil portion 2a has a lead wire 2b (first lead wire) connected to one end and a lead wire 2d (second lead wire) connected to the other end. Furthermore, the lead wire 2b is provided with an electrode 2c that functions as an electrode, and the lead wire 2d is provided with an electrode 2e that functions as an electrode. The coil portion 2a and the lead wires 2b and 2d form a single first conductor 2. Note that the lead wires 2b and 2d are also terminals extending from one end of the coil portion 2a, and are therefore also referred to as terminals 2b and 2d.

[0016] The coil portion 3a has one end connected to a lead wire 3b (third lead wire) and the other end connected to a lead wire 3d (fourth lead wire). Furthermore, the lead wire 3b is provided with an electrode 3c that functions as an electrode, and the lead wire 3d is provided with an electrode 3e that functions as an electrode. The coil portion 3a and the lead wires 3b and 3d form a single second conductor 3. The lead wires 3b and 3d are also terminals extending from one end of the coil portion 3a, and are therefore also referred to as terminals 3b and 3d.

[0017] The first conductor 2 including the coil L1 and the second conductor 3 including the coil L2 are formed by punching out a pattern from a single metal plate and bending the punched pattern. The bent portions between the coil L1 (coil portion 2a) and the lead wires 2b and 2d, and the bent portions between the electrodes 2c and 2e and the other regions of the lead wires 2b and 2d, are formed by bending, resulting in a substantially right-angle structure with a radius of curvature. Similarly, the bent portions between the coil L2 (coil portion 3a) and the lead wires 3b and 3d, and the bent portions between the electrodes 3c and 3e and the other regions of the lead wires 3b and 3d, are also formed by bending, resulting in a substantially right-angle structure with a radius of curvature. In this way, the bent portions form arcs with a constant radius. The first conductor 2 and the second conductor 3 may also be formed from one or more wires, and the wires may be similarly bent to form arcs with a constant radius at the bent portions.

[0018] The coils L1 and L2 are arranged so that their openings overlap. While FIG. 1A shows an example in which the openings nearly overlap, the openings may be offset as long as magnetic field coupling is achieved, and it is sufficient that at least 50% of each opening overlaps. A magnetic field is generated in the coil L1 when a current flows from the electrode 2c of the first conductor 2, and a magnetic field in the same direction as the magnetic field of the coil L1 is generated in the coil L2 when a current flows from the electrode 2e to the coil L2 through the electrode 3e of the second conductor 3. The coils L1 and L2 are connected at the electrode 2e and the electrode 3e on the mounting board.

[0019] At the positions where the coil portion 2a connects to the lead wires 2b and 2d, the closer the distance between the lead wires 2b and 2d, the closer the coil opening, thereby increasing inductance. On the other hand, the electrodes 2c and 2e are spaced farther apart to prevent short circuits when mounted on a mounting board. Similarly, at the positions where the coil portion 3a connects to the lead wires 3b and 3d, the closer the distance between the lead wires 3b and 3d, the closer the coil opening, thereby increasing inductance. On the other hand, the electrodes 3c and 3e are spaced farther apart to prevent short circuits when mounted on a mounting board. Thus, the lead wires 2b and 2d are shaped to spread outward from their lead wire positions on the left side surface 44 before extending to the bottom surface 42. Similarly, the lead wires 3b and 3d are shaped to spread outward from their lead wire positions on the right side surface 43 before extending to the bottom surface 42.

[0020] 1A, the Y-axis direction is the direction along the first side that is the boundary between the plane 41 and the right side surface 43, the X-axis direction is the direction parallel to the plane 41 and perpendicular to the Y-axis direction, and the Z-axis direction is the direction perpendicular to the plane 41. As shown in Fig. 1A, the housing 4 has a main body in the shape of a rectangular parallelepiped, and a convex portion 4a protrudes in the X-axis direction from the right side surface 43 of the surface of the housing 4, and a convex portion 4b protrudes in the X-axis direction from the left side surface 44 of the surface of the housing 4.

[0021] The protrusions 4a are shaped to extend along portions of the lead lines 3b and 3d. The protrusions 4a are disposed adjacent to and opposite the lead lines 3b and 3d, and are disposed so as to at least partially overlap the lead lines 3b and 3d when viewed in the Y-axis direction or the Z-axis direction, which are perpendicular to the X-axis direction from which the protrusions 4a protrude. The protrusions 4a are adjacent to the lead lines 3b and 3d in the Y-axis direction and the Z-axis direction. The lead lines 3b and 3d are connected to the substrate at the electrodes 3c and 3e.

[0022] The lead wires 3b and 3d tend to deform when an external force such as vibration is applied to the housing 4 from above and below or from the front and back. When an external force is applied to the housing 4, the protrusion 4a comes into contact with at least a part of the lead wire 3b or the lead wire 3d, thereby supporting the lead wire 3b or the lead wire 3d.

[0023] The protrusions 4b are shaped to extend along portions of the lead lines 2b and 2d. The protrusions 4b are disposed adjacent to and opposite the lead lines 2b and 2d, and are disposed so as to at least partially overlap the lead lines 2b and 2d when viewed in the Y-axis direction or the Z-axis direction, which are perpendicular to the X-axis direction from which the protrusions 4b protrude. The protrusions 4b are adjacent to the lead lines 2b and 2d in the Y-axis direction and the Z-axis direction. The lead lines 2b and 2d are connected to the substrate at the portions of the electrodes 2c and 2e.

[0024] The lead wires 2b and 2d tend to deform when an external force such as vibration is applied to the housing 4 from above and below or from the front and back. When an external force is applied to the housing 4, the protrusion 4b abuts against at least a part of the lead wire 2b or the lead wire 2d, thereby supporting the lead wire 2b or the lead wire 2d.

[0025] Here, the first conductor 2 and the second conductor 3 are formed by deforming a metal plate, and the cross section of the metal plate in the thickness direction and the side surfaces of the protrusions 4a and 4b are close to each other in two directions. If the first conductor 2 and the second conductor 3 interfere with the protrusions 4a and 4b, stress will be generated in the first conductor 2 or the second conductor 3 regardless of external force, which will affect reliability. Therefore, taking into account manufacturing variations, the first conductor 2 and the second conductor 3 are arranged with a gap between them and the protrusions 4a and 4b. However, the cross section of the metal plate in the thickness direction may partially contact the side surfaces of the protrusions 4a and 4b.

[0026] The first conductor 2 and the second conductor 3 are formed from metal plates, such as copper or an alloy of copper and other metals. Copper is a relatively soft metal with low electrical resistance. Therefore, under conditions of repeated low and high temperatures (e.g., a heat cycle test), the lead wires 2b, 2d, 3b, and 3d expand and contract due to heat. The coil component 1 has gaps between the protrusion 4a and the lead wires 3b and 3d, and between the protrusion 4b and the lead wires 2b and 2d, so that they do not interfere with each other or are subjected to unnecessary stress even when thermally contracted.

[0027] In addition, the above-mentioned proximity of the convex portion 4a to the lead wires 3b, 3d (proximity of the convex portion 4b to the lead wires 2b, 2d) means that there is a gap that takes into account manufacturing variations and thermal shrinkage, and the upper limit of this gap should be within the allowable range of deformation of the first conductor 2 and the second conductor 3 due to external forces.

[0028] When an external force is applied to the housing 4 from above, below, or from the front, back, and rear, the coil component 1 can prevent deformation of the lead wires 3b, 3d, 2b, and 2d because the lead wires 3b and 3d are supported by the protrusion 4a and the lead wires 2b and 2d are supported by the protrusion 4b. Even when the coil component 1 is deformed due to thermal expansion and contraction, the expansion and contraction of the metal can be absorbed by the small gaps provided between the protrusion 4a and the lead wires 3b and 3d and between the protrusion 4b and the lead wires 2b and 2d.

[0029] Although the housing 4 is shown in a rectangular parallelepiped shape in FIG. 1A, the side surfaces may be inclined as long as the bottom surface 42, which serves as the mounting surface, and the coil surface are approximately parallel, and the housing 4 may be, for example, a trapezoid in which the area of ​​the bottom surface 42 is larger than the area of ​​the flat surface 41.

[0030] 2 is a circuit diagram of a filter circuit 100 including the coil device 1 according to the first embodiment. The filter circuit 100 is, for example, an EMI removal filter, and is a third-order T-type LC filter circuit. In this filter circuit 100, the electrode 2c is connected to a power supply (not shown), and the electrode 3c is connected to a circuit (not shown) such as a DC / DC converter or a power supply module. The filter circuit 100 passes necessary components of the current flowing from the power supply to the circuit and removes unnecessary components.

[0031] Specifically, a direct current is passed through the filter circuit 100, and high-frequency noise contained in the direct current is dropped to GND via capacitor C1. Capacitor C1, which is a capacitance element, has an equivalent series inductance (ESL) (La), which prevents high-frequency noise from passing through it, degrading noise removal performance. This filter circuit 100 uses negative inductance generated in series with capacitor C1 due to the mutual inductance caused by the magnetic coupling of the two coils to cancel the capacitor's ESL (La), thereby maintaining high noise removal performance.

[0032] In the following embodiment, a third-order T-type LC filter circuit will be used as the configuration of the filter circuit 100, but coil components with similar configurations can also be applied to fifth-order T-type LC filter circuits or higher-order T-type LC filter circuits. As shown in Fig. 2, the filter circuit 100 includes a coil component 1 and a capacitor C1. The coil component 1 includes electrodes 2c and 3c, an intermediate terminal T (electrodes 2e and 3e), a coil L1, and a coil L2.

[0033] As shown in FIG. 2, one end of the capacitor C1 is connected to the intermediate terminal T, and the other end is connected to the GND wiring. The capacitor C1 is made of BaTiO ３The present invention is not limited to multilayer ceramic capacitors primarily composed of barium titanate (barium titanate), but may also include multilayer ceramic capacitors primarily composed of other materials, or other types of capacitors other than multilayer ceramic capacitors, such as aluminum electrolytic capacitors. Capacitor C1 has an inductor La as a parasitic inductance (equivalent series inductance (ESL)), and is equivalent to a circuit configuration in which inductor La is connected in series with capacitor C1a. Capacitor C1 may also be equivalent to a circuit configuration in which parasitic resistance (equivalent series resistance (ESR)) is connected in series with inductor La and capacitor C1a.

[0034] In addition to the capacitor C1, coils L1 and L2 are also connected to the intermediate terminal T. The coils L1 and L2 are magnetically coupled and have mutual inductance. A negative inductance component of the same magnitude as the mutual inductance is generated between the intermediate terminal T and the capacitor C1. This negative inductance component can be used to cancel out the parasitic inductance (inductor La) of the capacitor C1, thereby making the parasitic inductance component of the capacitor C1 appear smaller. In other words, the filter circuit 100, which is composed of the capacitor C1, coil L1, and coil L2, cancels out the parasitic inductance of the capacitor C1 with the negative inductance component due to the mutual inductance between coils L1 and L2, thereby suppressing a decrease in the noise suppression effect in the high frequency band caused by the parasitic inductance of the capacitor C1 and improving the noise suppression effect of the filter circuit 100.

[0035] <Embodiment 2> In embodiment 2, a configuration will be described in which, unlike embodiment 1, the convex portion is located on the bottom surface of the housing 4 rather than on the side surface. FIG. 3A is a perspective view of a coil component 1A according to embodiment 2. FIG. 3B is a front view of the coil component 1A according to embodiment 2. FIG. 3C is a rear view of the coil component 1A according to embodiment 2. FIG. 3D is a right side view of the coil component 1A according to embodiment 2. FIG. 3E is a left side view of the coil component 1A according to embodiment 2. FIG. 3F is a plan view of the coil component 1A according to embodiment 2. FIG. 3G is a bottom view of the coil component 1A according to embodiment 2. FIG. 3H is a cross-sectional view taken along line 3H-3H in the plan view of the coil component 1A according to embodiment 2. Note that in the coil component 1A shown in embodiment 2, the same components as those in the coil component 1 according to embodiment 1 are designated by the same reference numerals, and detailed description thereof will not be repeated.

[0036] Coil component 1A has protrusions 4c on bottom surface 42, which is the bottom surface of housing 4. Protrusions 4c are cross-shaped protrusions that are disposed between each of lead wires 2b, 2d, 3b, and 3d and extend in the X-axis and Y-axis directions. Protrusions 4c are formed by cutting out four corners of housing 4. Coil component 1A has small gaps between protrusions 4c and electrodes 2c, 2e, 3c, and 3e, which are part of lead wires 2b, 2d, 3b, and 3d, taking thermal expansion and contraction into consideration.

[0037] The protrusions 4c are disposed close to and opposite the electrodes 2c, 2e, 3c, and 3e that are part of the leads 2b, 2d, 3b, and 3d, and are disposed so as to at least partially overlap the electrodes 2c, 2e, 3c, and 3e when viewed from the X-axis direction or the Y-axis direction that are perpendicular to the Z-axis direction from which the protrusions 4c protrude. The protrusions 4c are close to the electrodes 2c, 2e, 3c, and 3e in the X-axis direction and the Y-axis direction.

[0038] Lead wires 2b, 2d, 3b, and 3d are connected to the substrate at electrodes 2c, 2e, 3c, and 3e. Lead wires 2b, 2d, 3b, and 3d tend to deform when external force such as vibration is applied to housing 4 from the front, back, left, or right. When external force is applied to housing 4, protrusion 4c abuts against electrode 2c, which is part of lead wire 2b, electrode 2e, which is part of lead wire 2d, electrode 3c, which is part of lead wire 3b, and electrode 3e, which is part of lead wire 3d. Thus, by supporting each electrode 2c, 2e, 3c, and 3e on protrusion 4c, deformation of lead wires 2b, 2d, 3b, and 3d, including electrodes 2c, 2e, 3c, and 3e, can be prevented. In the coil component 1A, a small gap is provided between the protrusion 4c and the electrodes 2c, 2e, 3c, and 3e, which are part of the lead wires 2b, 2d, 3b, and 3d, so that the gap can absorb the expansion and contraction of the metal even when the coil component 1A is deformed due to thermal expansion and contraction.

[0039] Here, the surface of the protrusion 4c on the bottom surface 42 side is located within the thickness range of the electrodes 2c, 2e, 3c, and 3e, which are part of the lead-out wires 2b, 2d, 3b, and 3d. In other words, the electrodes 2c, 2e, 3c, and 3e, which are part of the lead-out wires 2b, 2d, 3b, and 3d, are arranged so that they partially overlap with the protrusion 4c in the height direction (Z-axis direction) of the housing 4 and are located outside the protrusion 4c. This is because if the electrodes 2c, 2e, 3c, and 3e were located inside the protrusion 4c, there is a possibility that the mounting board and the electrodes 2c, 2e, 3c, and 3e would not be connected during mounting; therefore, by positioning them outside, the purpose is to ensure reliable mounting on the mounting board.

[0040] <Embodiment 3> In embodiment 3, a configuration having a different shape of the side surface compared to embodiment 1 will be described. Fig. 4A is a perspective view of coil component 1B according to embodiment 3. Fig. 4B is a front view of coil component 1B according to embodiment 3. Fig. 4C is a right side view of coil component 1B according to embodiment 3. Fig. 4D is a bottom view of coil component 1B according to embodiment 3. Note that in coil component 1B shown in embodiment 3, the same components as those in coil component 1 according to embodiment 1 are designated by the same reference numerals and detailed description thereof will not be repeated.

[0041] The coil component 1B has a shape in which a protrusion 4a and a protrusion 4d protrude in the X-axis direction from the right side surface 43 of the housing 4. The protrusion 4d is provided along a portion of the lead wires 3b, 3d. The protrusion 4d is disposed close to and opposite the lead wires 3b, 3d, and is disposed so as to at least partially overlap with the lead wires 3b, 3d when viewed from the Y-axis direction or the Z-axis direction perpendicular to the X-axis direction from which the protrusion 4d protrudes. The protrusion 4d is close to the lead wires 3b, 3d in the Y-axis direction and the Z-axis direction.

[0042] The protrusion 4d is provided on the opposite side of the lead wires 3b and 3d from the protrusion 4a. The protrusion 4d supports the lead wires 3b and 3d at a position above the protrusion 4a. Specifically, the protrusion 4d has an inverted U-shape that is provided along the lead wires 3b and 3d. The protrusion 4d prevents deformation of the lead wires 3b and 3d in the Y-axis direction and the Z-axis direction.

[0043] Coil component 1B has a shape in which protrusion 4b and protrusion 4e protrude in the X-axis direction from the left side surface 44 of housing 4. Protrusion 4e is provided along a portion of lead-out wires 2b and 2d. Protrusion 4e is disposed close to and opposite lead-out wires 2b and 2d, and is disposed so as to at least partially overlap lead-out wires 2b and 2d when viewed from the Y-axis direction or the Z-axis direction perpendicular to the X-axis direction from which protrusion 4e protrudes. Protrusion 4e is close to lead-out wires 2b and 2d in the Y-axis direction and the Z-axis direction.

[0044] The protrusion 4e is provided on the opposite side of the lead wires 2b and 2d from the protrusion 4b. The protrusion 4e supports the lead wires 2b and 2d at a position above the protrusion 4b. Specifically, the protrusion 4e has an inverted U-shape that is provided along the lead wires 2b and 2d. The protrusion 4e prevents deformation of the lead wires 2b and 2d in the Y-axis direction and the Z-axis direction.

[0045] In coil component 1B, slight gaps are provided between protrusion 4a and lead wires 3b and 3d, and between protrusion 4d and lead wires 3b and 3d, taking thermal expansion and contraction into consideration. In coil component 1B, slight gaps are provided between protrusion 4b and lead wires 2b and 2d, and between protrusion 4e and lead wires 2b and 2d, taking thermal expansion and contraction into consideration.

[0046] Lead wires 3b and 3d are connected to the substrate at electrodes 3c and 3e. Lead wires 3b and 3d tend to deform when an external force such as vibration is applied to housing 4 from above, below, front, or back. Lead wires 2b and 2d are connected to the substrate at electrodes 2c and 2e. Lead wires 2b and 2d tend to deform when an external force such as vibration is applied to housing 4 from above, below, front, or back.

[0047] When an external force is applied to the housing 4, the coil component 1B can prevent deformation of the lead wires 2b, 2d, 3b, and 3d because the lead wires 3b and 3d are supported by the protrusions 4a and 4d and the lead wires 2b and 2d are supported by the protrusions 4b and 4e. Even when the coil component 1B is deformed due to thermal expansion and contraction, the expansion and contraction of the metal can be absorbed by the small gaps provided between the protrusions 4a and 4d and the lead wires 3b and 3d, and between the protrusions 4b and 4e and the lead wires 2b and 2d.

[0048] <Fourth Embodiment> In the fourth embodiment, a configuration in which the shapes of the side and bottom surfaces are different from those of the first embodiment will be described. Fig. 5A is a perspective view of a coil component 1C according to the fourth embodiment. Fig. 5B is a front view of the coil component 1C according to the fourth embodiment. Fig. 5C is a right side view of the coil component 1C according to the fourth embodiment. Fig. 5D is a bottom view of the coil component 1C according to the fourth embodiment. Note that in the coil component 1C shown in the fourth embodiment, the same components as those in the coil component 1 according to the first embodiment are designated by the same reference numerals and detailed description thereof will not be repeated.

[0049] The coil device 1C has a shape in which a protrusion 4a and a protrusion 4d protrude in the X-axis direction from the right side surface 43 of the housing 4. The protrusions 4a and 4d are shaped to be provided along parts of the lead wires 3b and 3d. The protrusions 4a and 4d are disposed close to and opposite the lead wires 3b and 3d, and are disposed so as to at least partially overlap with the lead wires 3b and 3d when viewed from the Y-axis direction or the Z-axis direction perpendicular to the X-axis direction from which the protrusions 4a and 4d protrude. The protrusions 4a and 4d are close to the lead wires 3b and 3d in the Y-axis direction and the Z-axis direction.

[0050] The coil device 1C has a shape in which a protrusion 4b and a protrusion 4e protrude in the X-axis direction from the left side surface 44 of the housing 4. The protrusions 4b and 4e are shaped to be provided along parts of the lead wires 2b and 2d. The protrusions 4b and 4e are disposed close to and opposite the lead wires 2b and 2d, and are disposed so as to at least partially overlap with the lead wires 2b and 2d when viewed from the Y-axis direction or the Z-axis direction, which are perpendicular to the X-axis direction from which the protrusions 4b and 4e protrude. The protrusions 4b and 4e are close to the lead wires 2b and 2d in the Y-axis direction and the Z-axis direction.

[0051] The coil device 1C has protrusions 4c on the bottom surface 42, which is the bottom surface of the housing 4. The protrusions 4c are cross-shaped protrusions disposed between the lead wires 2b, 2d, 3b, and 3d and extending in the X-axis direction and the Y-axis direction. The protrusions 4c have a shape in which protrusions 4a and 4b are further provided at the tips of the cross-shaped protrusions in the X-axis direction. The protrusions 4c are disposed adjacent to and opposite the electrodes 2c, 2e, 3c, and 3e, which are part of the lead wires 2b, 2d, 3b, and 3d, and are disposed so as to at least partially overlap the electrodes 2c, 2e, 3c, and 3e when viewed from the X-axis direction or the Y-axis direction, which are perpendicular to the Z-axis direction from which the protrusions 4c protrude. The protrusions 4c are adjacent to the electrodes 2c, 2e, 3c, and 3e in the X-axis direction and the Y-axis direction.

[0052] In the coil component 1C, small gaps are provided between the protrusions 4a, 4d and the lead wires 3b, 3d, between the protrusions 4b, 4e and the lead wires 2b, 2d, and between the protrusion 4c and the electrodes 2c, 2e, 3c, 3e which are part of the lead wires 2b, 2d, 3b, 3d, to take thermal expansion and contraction into consideration.

[0053] Lead wires 3b and 3d are connected to the substrate at electrodes 3c and 3e. Lead wires 3b and 3d tend to deform when an external force such as vibration is applied to housing 4 from above, below, front, or back. Lead wires 2b and 2d are connected to the substrate at electrodes 2c and 2e. Lead wires 2b and 2d tend to deform when an external force such as vibration is applied to housing 4 from above, below, front, or back.

[0054] When an external force is applied to the housing 4 from above, below, or from the front, back, or left, or right, the coil device 1C has the leads 3b and 3d supported by the protrusions 4a and 4d, and the leads 2b and 2d supported by the protrusions 4b and 4e, as shown by the arrows in Fig. 5C. When an external force is applied to the housing 4 from above, below, or from the front, back, or left, as shown by the arrows in Fig. 5D, the coil device 1C has the leads 2b, 2d, 3b, and 3d supported by the protrusions 4c, as shown by the arrows in Fig. 5D. This prevents deformation of the leads 2b, 2d, 3b, and 3d in the coil device 1C even when an external force is applied to the housing 4 from multiple directions.

[0055] In coil device 1C, slight gaps are provided between protrusions 4a, 4d and lead wires 3b, 3d, and between protrusions 4b, 4e and lead wires 2b, 2d, so that expansion and contraction of the metal can be absorbed by the gaps even when lead wires 2b, 2d, 3b, 3d are deformed due to thermal expansion and contraction. In coil device 1C, slight gaps are provided between protrusion 4c and electrodes 2c, 2e, 3c, 3e, which are part of lead wires 2b, 2d, 3b, 3d, so that expansion and contraction of the metal can be absorbed by the gaps even when electrodes 2c, 2e, 3c, 3e are deformed due to thermal expansion and contraction.

[0056] It is sufficient that the housing 4 is provided with at least one of the protrusions 4a, 4d, 4b, 4e, and 4c, and the protrusions may be provided in a combination of two or more of the plurality of protrusions. For example, the housing 4 may be provided with a protrusion 4d on the right side and a protrusion 4c on the bottom. The protrusion 4c on the bottom may not be cross-shaped but may extend in one direction.

[0057] Next, a modified example of the fourth embodiment will be described. A coil component 1CA according to the modified example of the fourth embodiment differs from the coil component 1C according to the fourth embodiment in that it includes a protrusion 4m and a protrusion 4n. Fig. 5E is a right side view of the coil component 1CA according to the modified example of the fourth embodiment. Fig. 5F is a bottom view of the coil component 1CA according to the modified example of the fourth embodiment.

[0058] Coil component 1CA has a shape in which a convex portion 4m protrudes in the Y-axis direction from a back surface 46, which is the third side surface of the housing 4. Convex portion 4m is provided along a portion of lead wire 2b (first lead wire) and a portion of lead wire 3b (third lead wire). Coil component 1CA has a shape in which a convex portion 4n protrudes in the Y-axis direction from a front surface 45, which is the fourth side surface of the housing 4. Convex portion 4n is provided along a portion of lead wire 2d (second lead wire) and a portion of lead wire 3d (fourth lead wire).

[0059] The protrusions 4m are located close to the lead lines 2b and 3b and are arranged so as to overlap at least partially with the lead lines 2b and 3b when viewed from the X-axis direction or the Z-axis direction perpendicular to the Y-axis direction from which the protrusions 4m protrude. The protrusions 4m are located close to the lead lines 2b and 3b in the Y-axis direction. The protrusions 4n are located close to the lead lines 2d and 3d and are arranged so as to overlap at least partially with the lead lines 2d and 3d when viewed from the X-axis direction or the Z-axis direction perpendicular to the Y-axis direction from which the protrusions 4n protrude. The protrusions 4n are located close to the lead lines 2d and 3d in the Y-axis direction.

[0060] 5E and 5F, the protrusions 4m and 4n are configured to be attached separately to the outer layer of the housing 4. The protrusions 4m and 4n may not be attached separately, but may be formed integrally with the housing 4. The protrusions 4m and 4n may be similarly provided in other embodiments as well.

[0061] In the coil component 1CA, small gaps are provided between the protrusions 4a, 4d, 4m, 4n and the lead wires 3b, 3d, between the protrusions 4b, 4e, 4m, 4n and the lead wires 2b, 2d, and between the protrusions 4c, 4m, 4n and the electrodes 2c, 2e, 3c, 3e, which are part of the lead wires 2b, 2d, 3b, 3d, to take thermal expansion and contraction into consideration.

[0062] Lead wires 3b and 3d are connected to the substrate at electrodes 3c and 3e. Lead wires 3b and 3d tend to deform when an external force such as vibration is applied to housing 4 from above, below, front, or back. Lead wires 2b and 2d are connected to the substrate at electrodes 2c and 2e. Lead wires 2b and 2d tend to deform when an external force such as vibration is applied to housing 4 from above, below, front, or back.

[0063] When an external force is applied to the housing 4 from above, below, or from the front, back, or left, or right, as shown by the arrows in Fig. 5E, the lead wires 3b and 3d are supported by the protrusions 4a, 4d, 4m, and 4n, and the lead wires 2b and 2d are supported by the protrusions 4b, 4e, 4m, and 4n. When an external force is applied to the housing 4 from above, below, or from the front, back, or left, as shown by the arrows in Fig. 5F, the lead wires 2c, which is part of the lead wire 2b, the electrode 2e, which is part of the lead wire 2d, the electrode 3c, which is part of the lead wire 3b, and the electrode 3e, which is part of the lead wire 3d, are supported by the protrusions 4c, 4m, and 4n. This allows the coil device 1CA to prevent deformation of the lead wires 2b, 2d, 3b, and 3d even when external forces are applied to the housing 4 from multiple directions.

[0064] In the coil component 1CA, slight gaps are provided between the protrusions 4a, 4d, 4m, 4n and the lead wires 3b, 3d, and between the protrusions 4b, 4e, 4m, 4n and the lead wires 2b, 2d, so that expansion and contraction of the metal can be absorbed by the gaps even when the lead wires 2b, 2d, 3b, 3d are deformed due to thermal expansion and contraction. In the coil component 1CA, slight gaps are provided between the protrusions 4c, 4m, 4n and the electrodes 2c, 2e, 3c, 3e that are part of the lead wires 2b, 2d, 3b, 3d, so that expansion and contraction of the metal can be absorbed by the gaps even when the electrodes 2c, 2e, 3c, 3e are deformed due to thermal expansion and contraction.

[0065] <Fifth Embodiment> In the fifth embodiment, a configuration having a different shape of the side surface compared to the first embodiment will be described. Fig. 6A is a perspective view of a coil component 1D according to the fifth embodiment. Fig. 6B is a front view of the coil component 1D according to the fifth embodiment. Fig. 6C is a right side view of the coil component 1D according to the fifth embodiment. Fig. 6D is a bottom view of the coil component 1D according to the fifth embodiment. Note that in the coil component 1D shown in the fifth embodiment, the same components as those in the coil component 1 according to the first embodiment are designated by the same reference numerals and detailed description thereof will not be repeated.

[0066] Coil component 1D has a shape in which protrusion 4i and protrusion 4g protrude in the X-axis direction from the right side surface 43 of the housing 4. Protrusion 4i is a triangular prism-shaped protrusion. Lead wires 3b and 3d are arranged so as to widen along protrusion 4i. Protrusion 4g is shaped to follow portions of lead wires 3b and 3d at a position above protrusion 4i. Coil component 1D has a shape in which protrusion 4j and protrusion 4h protrude in the X-axis direction from the left side surface 44 of the housing 4. Protrusion 4j is a triangular prism-shaped protrusion. Lead wires 2b and 2d are arranged so as to widen along protrusion 4j. Protrusion 4h is shaped to follow portions of lead wires 2b and 2d at a position above protrusion 4j.

[0067] In coil component 1D, slight gaps are provided between protrusion 4i and lead wires 3b and 3d, and between protrusion 4g and lead wires 3b and 3d, taking thermal expansion and contraction into consideration. In coil component 1D, slight gaps are provided between protrusion 4j and lead wires 2b and 2d, and between protrusion 4h and lead wires 2b and 2d, taking thermal expansion and contraction into consideration.

[0068] Lead wires 3b and 3d are connected to the substrate at electrodes 3c and 3e. Lead wires 3b and 3d tend to deform when an external force due to vibration or the like is applied to housing 4 from the front, back, or obliquely. Lead wires 2b and 2d are connected to the substrate at electrodes 2c and 2e. Lead wires 2b and 2d tend to deform when an external force due to vibration or the like is applied to housing 4 from the front, back, or obliquely.

[0069] 6C , when an external force is applied to the housing 4 from the front, rear, or obliquely, the coil device 1D can prevent deformation of the lead wires 2b, 2d, 3b, and 3d because the lead wires 3b and 3d are supported by the protrusions 4i and 4g and the lead wires 2b and 2d are supported by the protrusions 4j and 4h. Even when the coil device 1D is deformed due to thermal expansion and contraction, the expansion and contraction of the metal can be absorbed by the small gaps provided between the protrusions 4i and 4g and the lead wires 3b and 3d, and between the protrusions 4j and 4h and the lead wires 2b and 2d.

[0070] <Modifications> In the above-described embodiment, a portion of the lead wires 2b, 2d, 3b, and 3d may be arranged on the front surface 45 or the rear surface 46. In this case, the convex portion may be provided at a position along a portion of the front surface 45 or the rear surface 46. The convex portion may be formed separately from the housing 4.

[0071] The following describes the design features of the coil device 1A shown in Figures 3A to 3H. If this application is converted into a design application, the cross-shaped convex portion 4c on the bottom surface in the drawings can be considered a partial design and be included as the "design for which design registration is sought." Note that only the portion of the cross-shaped convex portion 4c extending to one side can be considered as the "design for which design registration is sought." Furthermore, any portion other than the convex portion 4c, or the design portion combining that portion with the convex portion 4c, can be considered as the "design for which design registration is sought." Furthermore, the design of the entire shape, including the convex portion 4c and the lead wires 2b, 2d, 3b, and 3d, can be considered as the "design for which design registration is sought." In other words, Figures 3A to 3H depict all aspects of the design that can be identified from those drawings.

[0072] <Aspects> (1) A coil component according to the present disclosure includes a housing having a pair of opposing first and second main surfaces and four side surfaces connecting the first and second main surfaces, a first coil section disposed inside the housing, a first coil conductor having a first lead wire and a second lead wire drawn from the first coil section, a second coil section disposed inside the housing and having an opening that at least partially overlaps with the opening of the first coil section, and a second coil conductor having a third lead wire and a fourth lead wire drawn from the second coil section. The first lead wire is drawn from the first side surface of the housing and extends to the second main surface. The second lead wire is drawn from the first side surface of the housing and extends to the second main surface. The third lead wire is drawn from the second side surface of the housing and extends to the second main surface. The fourth lead wire is drawn from the second side surface of the housing and extends to the second main surface. The housing has, on at least one surface, a protrusion adjacent to a portion of the first, second, third, and fourth draw-out lines, and the protrusion and the first, second, third, and fourth draw-out lines are arranged opposite each other in the adjacent region and overlap each other when viewed from any direction perpendicular to the direction in which the protrusions protrude.

[0073] According to the coil component of the present disclosure, each lead wire is supported by a protrusion, and therefore deformation of the lead wire can be prevented.

[0074] (2) A coil component according to (1), wherein the protrusion is adjacent to a portion of the first lead wire, the second lead wire, the third lead wire, and the fourth lead wire in two or more directions selected from the group consisting of a first direction along the first edge that is the boundary between the first main surface and the first side surface, a second direction that is parallel to the first main surface and perpendicular to the first direction, and a third direction that is perpendicular to the first main surface.

[0075] According to the coil component of the present disclosure, each lead wire is supported by the protrusion in two directions, and therefore deformation of the lead wire can be prevented.

[0076] (3) A coil component according to (1) or (2), wherein the convex portions are provided on the second main surface and have a cross shape and are arranged between the first lead wire, the second lead wire, the third lead wire, and the fourth lead wire.

[0077] According to the coil component of the present disclosure, the lead wires are supported by the cross-shaped protrusions, and therefore deformation of the lead wires can be prevented.

[0078] (4) The coil component according to (1) or (2), wherein the protrusions include a first protrusion and a second protrusion. The first protrusion is provided on the first side surface and has a shape that follows a portion of the first lead wire and a portion of the second lead wire. The second protrusion is provided on the second side surface and has a shape that follows a portion of the third lead wire and a portion of the fourth lead wire.

[0079] According to the coil component of the present disclosure, each lead wire is supported by the first convex portion and the second convex portion, and therefore deformation of the lead wire can be prevented.

[0080] (5) In the coil component according to (4), the protrusion further includes a third protrusion and a fourth protrusion. The third protrusion is provided on the first side surface and on an opposite side of the first protrusion with respect to the first lead wire and the second lead wire.

[0081] According to the coil component of the present disclosure, each lead wire is supported by the third convex portion and the fourth convex portion, and therefore deformation of the lead wire can be prevented.

[0082] (6) The coil component according to (1) or (2), wherein the protrusions include a first protrusion, a second protrusion, and a third protrusion. The first protrusion is provided on the first side surface and has a shape that follows a portion of the first lead wire and a portion of the second lead wire. The second protrusion is provided on the second side surface and has a shape that follows a portion of the third lead wire and a portion of the fourth lead wire. The third protrusion is provided on the second main surface and has a cross shape that is disposed between the first lead wire, the second lead wire, the third lead wire, and the fourth lead wire.

[0083] According to the coil component of the present disclosure, each lead wire is supported by the first convex portion, the second convex portion, and the third convex portion, and therefore deformation of the lead wire can be prevented.

[0084] (7) The coil component according to any one of (1) to (6), wherein the protrusions include a fifth protrusion and a sixth protrusion. The fifth protrusion is provided on a third side surface of the housing and has a shape that follows a portion of the first lead wire and a portion of the third lead wire. The sixth protrusion is provided on a fourth side surface of the housing and has a shape that follows a portion of the second lead wire and a portion of the fourth lead wire.

[0085] According to the coil component of the present disclosure, the lead wires are supported by the fifth convex portions, and therefore deformation of the lead wires can be prevented.

[0086] (8) The coil component according to any one of (1) to (7), wherein the first lead wire and the second lead wire are provided on the first side surface so as to spread outward from lead-out positions and extend to the second main surface, and the third lead wire and the fourth lead wire are provided on the second side surface so as to spread outward from lead-out positions and extend to the second main surface.

[0087] The coil component of the present disclosure can provide a large inductance and prevent short circuits.

[0088] (9) A coil component according to any one of (1) to (8), wherein the surface of the convex portion on the second main surface side is located inward compared to the surfaces of the first lead wire, the second lead wire, the third lead wire, and the fourth lead wire on the second main surface side.

[0089] According to the coil component of the present disclosure, it is possible to prevent each lead wire from being separated from the mounting substrate.

[0090] (10) In the coil component according to any one of (1) to (9), the first lead wire, the second lead wire, the third lead wire, and the fourth lead wire are mainly composed of copper.

[0091] According to the coil component of the present disclosure, each lead wire made of a soft metal such as copper can be favorably supported by the protruding portion.

[0092] (11) A filter circuit according to the present disclosure includes the coil component according to any one of (1) to (10) and a capacitor connected to the coil component.

[0093] According to the filter circuit of the present disclosure, it is possible to provide a filter circuit that prevents deformation of the lead wires.

[0094] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present disclosure is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims.

[0095] 1, 1A, 1B, 1C, 1D Coil component, 2 First conductor, 2a, 3a Coil portion, 2b, 2d, 3b, 3d Lead wire, 2c, 2e, 3c, 3e Electrode, 3 Second conductor, 4 Housing, 4a, 4b, 4c, 4d, 4e, 4g, 4h, 4i, 4j Convex portion, 41 Flat surface, 42 Bottom surface, 43 Right side surface, 44 Left side surface, 45 Front surface, 46 Rear surface, 100 Filter circuit, L1, L2 Coil.

Claims

1. A housing having a pair of first and second main surfaces opposed to each other and four side surfaces connecting the first and second main surfaces; a first coil section disposed inside the housing, and a first coil conductor having a first lead wire and a second lead wire drawn from the first coil section; a second coil section disposed inside the housing and having an opening that at least partially overlaps with an opening of the first coil section, and a second coil conductor having a third lead wire and a fourth lead wire drawn from the second coil section, wherein the first lead wire is drawn from a first side surface of the housing and extends to the second main surface, the second lead wire is drawn from the first side surface of the housing and extends to the second main surface, the third lead wire is drawn from the second side surface of the housing and extends to the second main surface, and the fourth lead wire is drawn from the second side surface of the housing and extends to the second main surface, The coil component has a protrusion on at least one surface thereof that is adjacent to a portion of the first outgoing wire, the second outgoing wire, the third outgoing wire, and the fourth outgoing wire, and the protrusion and the first outgoing wire, the second outgoing wire, the third outgoing wire, and the fourth outgoing wire are arranged opposite each other in an adjacent region and are arranged overlapping when viewed from any direction perpendicular to the direction in which the protrusion protrudes.

2. The coil component according to claim 1, wherein the convex portion is adjacent to a portion of the first lead wire, the second lead wire, the third lead wire, and the fourth lead wire in two or more directions selected from the group consisting of a first direction along a first side that is a boundary between the first main surface and the first side surface, a second direction that is parallel to the first main surface and perpendicular to the first direction, and a third direction that is perpendicular to the first main surface.

3. A coil component as described in claim 1 or claim 2, wherein the convex portion is provided on the second main surface and has a cross shape arranged between each of the first lead wire, the second lead wire, the third lead wire, and the fourth lead wire.

4. A coil component as described in claim 1 or claim 2, wherein the convex portion includes a first convex portion and a second convex portion, the first convex portion is provided on the first side surface and has a shape that follows a portion of the first lead-out wire and a portion of the second lead-out wire, and the second convex portion is provided on the second side surface and has a shape that follows a portion of the third lead-out wire and a portion of the fourth lead-out wire.

5. A coil component as described in claim 4, wherein the convex portion further includes a third convex portion and a fourth convex portion, the third convex portion being provided on the first side surface and being provided on the opposite side to the first convex portion with respect to the first lead wire and the second lead wire.

6. A coil component as described in claim 1 or 2, wherein the convex portion includes a first convex portion, a second convex portion, and a third convex portion, the first convex portion is provided on the first side surface and has a shape that follows a portion of the first lead-out wire and a portion of the second lead-out wire, the second convex portion is provided on the second side surface and has a shape that follows a portion of the third lead-out wire and a portion of the fourth lead-out wire, and the third convex portion is provided on the second main surface and has a cross shape that is disposed between each of the first lead-out wire, the second lead-out wire, the third lead-out wire, and the fourth lead-out wire.

7. A coil component according to any one of claims 1 to 6, wherein the convex portion includes a fifth convex portion and a sixth convex portion, the fifth convex portion is provided on a third side surface of the housing and has a shape that follows a portion of the first lead-out wire and a portion of the third lead-out wire, and the sixth convex portion is provided on a fourth side surface of the housing and has a shape that follows a portion of the second lead-out wire and a portion of the fourth lead-out wire.

8. A coil component described in any one of claims 1 to 7, wherein the first and second lead-out wires are arranged so as to spread outward from a lead-out position on the first side surface and extend toward the second main surface, and the third and fourth lead-out wires are arranged so as to spread outward from a lead-out position on the second side surface and extend toward the second main surface.

9. A coil component described in any one of claims 1 to 8, wherein the surface of the protrusion on the second main surface side is located inward compared to the surfaces of the first lead-out wire, the second lead-out wire, the third lead-out wire, and the fourth lead-out wire on the second main surface side.

10. A coil component according to any one of claims 1 to 9, wherein the first lead wire, the second lead wire, the third lead wire, and the fourth lead wire are primarily composed of copper.

11. A filter circuit comprising: the coil component according to any one of claims 1 to 10; and a capacitor connected to the coil component.

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