Coil components and filter circuits

Abstract

Provided are: a coil component in which two wires are wrapped in opposite directions, the coil component having a structure that is easy to produce; and a filter circuit in which said coil component is mounted. The coil component (1) according to the present disclosure comprises: a bobbin (2) that includes a body section (2a) around which wires are wound, and a first collar section (2b) and second collar section (2c) provided at both ends of the body section (2a); and a first wire (4) and second wire (5) wound around the body section (2a). The bobbin (2) includes a plurality of mounting terminals (6a-6d) and a plurality of connection terminals (8a-8d). On surfaces of the coil component (1) having depressions (7a, 7b) respectively provided in one surface of the first collar section (2b) and one surface of the second collar section (2c), the first connection terminal (8a) is located at a position diagonal from the second connection terminal (8b), and the third connection terminal (8c) is located at a position diagonal from the fourth connection terminal (8d).

Description

Technical Field

[0001] The present disclosure relates to a coil component and a filter circuit on which the coil component is mounted.

Background Art

[0002] Filter circuits are used in electronic devices as a noise countermeasure. Examples of filter circuits include EMI (Electro-Magnetic Interference) removal filters, which include a capacitor that is a capacitance element and a coil component in which two coils are magnetically coupled.

[0003] In the coil component included in the filter circuit, it is preferable to stabilize the coupling coefficient. In a coil component, in order to stabilize the coupling coefficient, a configuration of a coil component in which a depression is made inside the mounting terminal of the flange portion and the distance between wires is made constant is known (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The coil component described in Patent Document 1 is manufactured by first crimping the two wires into a recess in one flange, then winding the two wires around the body, and finally crimping the two wires into a recess in the other flange, since the winding direction of the two magnetically coupled coils is the same. If the two wires are wound in the same direction, as in the coil component described in Patent Document 1, the work is easy because both wires can be crimped into the flange recesses at the same time. However, if the two wires are wound in opposite directions, it is not possible to wind both wires around the body at the same time, and therefore it is not possible to crimp both wires into the flange recesses at the same time. In other words, with one wire already crimped into the flange recess, the other wire must be crossed and crimped into the flange recess, resulting in a crimping operation in a narrow space and making the manufacture of the coil component difficult.

[0006] The purpose of this disclosure is to provide a coil component having an easily manufactured structure, in which two wires are wound in opposite directions, and a filter circuit on which said coil component is mounted. [Means for solving the problem]

[0007] A coil component according to one embodiment of the present disclosure is a coil component having a first coil and a second coil. The coil component comprises a bobbin having a body portion around which a wire is wound, and a first flange portion and a second flange portion provided at both ends of the body portion, a first wire wound around the body portion to form the first coil, and a second wire wound around the body portion in the opposite direction to the first wire to form the second coil. The bobbin includes a plurality of mounting terminals formed on one surface of the first flange portion and the second flange portion for mounting the coil component on a substrate, and a plurality of connection terminals formed on one surface of the first flange portion and the second flange portion for connecting the ends of the first wire and the second wire. Of the multiple mounting terminals, the first mounting terminal is formed on one surface of the first flange and is electrically connected to a first connecting terminal that connects to one end of the first wire; the second mounting terminal is formed on one surface of the second flange and is electrically connected to a second connecting terminal that connects to the other end of the first wire; the third mounting terminal is formed on one surface of the first flange and is electrically connected to a third connecting terminal that connects to one end of the second wire; and the fourth mounting terminal is formed on one surface of the second flange and is electrically connected to a fourth connecting terminal that connects to the other end of the second wire. On the surface of the coil component having recesses provided on one surface of the first flange and the second flange, the first connecting terminal is diagonally opposite to the second connecting terminal, and the third connecting terminal is diagonally opposite to the fourth connecting terminal. The recess formed in the first flange has a first bottom surface at a first depth and a second bottom surface at a second depth greater than the first depth, and the first mounting terminal and the third mounting terminal are provided on the first bottom surface. .

[0008] A filter circuit according to one embodiment of the present disclosure comprises the above-mentioned coil component, a substrate on which the coil component is mounted, and a capacitor mounted on the substrate, with one electrode electrically connected to the second and fourth mounting terminals of the coil component. [Effects of the Invention]

[0009] According to one embodiment of this disclosure, since the first connecting terminal is located diagonally to the second connecting terminal and the third connecting terminal is located diagonally to the fourth connecting terminal, there is no need to cross the wires and crimp them into the recesses formed in the flange, making it easier to manufacture coil components. [Brief explanation of the drawing]

[0010] [Figure 1] This is a perspective view of a coil component according to Embodiment 1. [Figure 2] This is a perspective view of the coil component according to Embodiment 1, viewed from a different direction. [Figure 3] This is a bottom view of the coil component according to Embodiment 1. [Figure 4] This is a plan view of a circuit board on which a coil component according to Embodiment 1 is mounted. [Figure 5] This is a circuit diagram of the filter circuit according to Embodiment 1. [Figure 6] This diagram illustrates the relationship between the width of the body and the width of the recess in a coil component. [Figure 7] This diagram illustrates the range of connection terminals used to connect the ends of wires in coil components. [Figure 8] This is a perspective view of a coil component according to Embodiment 2. [Figure 9] This is a perspective view of the coil component according to Embodiment 2, viewed from a different direction. [Figure 10] This is a bottom view of the coil component according to Embodiment 2. [Figure 11] This is a plan view of a circuit board on which a coil component according to Embodiment 2 is mounted. [Figure 12] This diagram illustrates the shape of the recess formed in the flange portion of a coil component. [Figure 13] This diagram illustrates a different shape of recess formed in the flange portion of a coil component. [Modes for carrying out the invention]

[0011] <Embodiment 1> The coil component according to Embodiment 1 will be described below. FIG. 1 is a perspective view of the coil component 1 according to Embodiment 1. FIG. 2 is a perspective view of the coil component 1 according to Embodiment 1 as viewed from another direction. FIG. 3 is a bottom view of the coil component 1 according to Embodiment 1. When the X-axis, Y-axis, and Z-axis are defined as shown in FIGS. 1 to 3, the X-axis direction is the length direction of the coil component 1, the Y-axis direction is the width direction of the coil component 1, and the Z-axis direction is the height direction of the coil component 1.

[0012] The coil component 1 is, for example, a transformer coil mounted on a filter circuit used for noise countermeasures in a power line. As will be described later, the coil component 1 includes two magnetically coupled coils in order to cancel the parasitic inductance of a capacitor mounted on the filter circuit.

[0013] The coil component 1 includes a bobbin 2, a first wire 4, and a second wire 5. The bobbin 2 has a body portion 2a around which a wire is wound, and first flange portions 2b and second flange portions 2c provided at both ends of the body portion 2a. The bobbin 2 is made of a non-conductive material, specifically, a non-magnetic material such as alumina, a magnetic material such as Ni-Zn ferrite, or a resin. When the bobbin 2 is made of a resin, for example, it is made of a resin containing magnetic powder such as metal powder or ferrite powder, a resin containing non-magnetic powder such as silica powder, or a resin not containing fillers such as powder.

[0014] The shape of the body portion 2a of the bobbin 2 is, for example, a prism. In the present disclosure, the body portion 2a is described as a prism, but it may be a cylinder or a polyhedron. In the coil component 1, the first wire 4 and the second wire 5 are directly wound around the body portion 2a. The first wire 4 and the second wire 5 are, for example, copper wires and are entirely covered with an insulating material.

[0015] In the coil component 1, the first wire 4 and the second wire 5 are wound around the body portion 2a in opposite directions to form two coils. Also, in the coil component 1, the first wire 4 is wound around the body portion 2a once to form the first coil L1, and the second wire 5 is wound around the body portion 2a once to form the second coil L2. Note that the single winding of the first wire 4 and the second wire 5 is just an example, and multiple windings may be used instead.

[0016] In the coil component 1, the length of the wire (the length of the wire wound around the body portion 2a) and the distance between the wires have a great influence on the coupling coefficient. The coil component 1 has the first wire 4 and the second wire 5 wound around the body portion 2a to keep the length of the wire constant in order to stabilize the coupling coefficient.

[0017] Furthermore, in order to keep the distance between the wires constant to stabilize the coupling coefficient, the coil component 1 is provided with connection terminals 8a to 8d in the depressions 7a and 7b formed in the flange portion to connect and fix the first wire 4 and the second wire 5. Specifically, one end of the first wire 4 is connected to the connection terminal 8a (the first connection terminal) by thermocompression bonding in the depression 7a formed in the first flange portion 2b. The other end of the first wire 4 is connected to the connection terminal 8b (the second connection terminal) by thermocompression bonding in the depression 7b formed in the second flange portion 2c. As shown in FIG. 3, on the surface (bottom surface) of the coil component 1 provided with the depressions 7a and 7b, the connection terminal 8a is provided at a diagonal position with respect to the connection terminal 8b. Also, the connection method between the end of the first wire 4 and the connection terminals 8a and 8b is not limited to thermocompression bonding, and for example, laser welding or the like may be used. Note that the depression provided on one surface of the flange portion may be formed by forming a recess in the flange portion or by changing the thickness of the mounting terminal.

[0018] Furthermore, one end of the second wire 5 is connected to the connection terminal 8c (third connection terminal) by thermocompression in a recess 7a formed in the first flange portion 2b. The other end of the second wire 5 is connected to the connection terminal 8d (fourth connection terminal) by thermocompression in a recess 7b formed in the second flange portion 2c. As shown in Figure 3, on the surface (bottom surface) of the coil component 1 where the recesses 7a and 7b are provided, the connection terminal 8c is located diagonally opposite to the connection terminal 8d. Also, the method of connecting the end of the second wire 5 to the connection terminals 8c and 8d is not limited to thermocompression, but may be, for example, laser welding.

[0019] In coil component 1, as shown in Figure 3, connection terminals 8a and 8b for fixing both ends of the first wire 4 are arranged on one diagonal on one side (bottom surface) of coil component 1, and connection terminals 8c and 8d for fixing both ends of the second wire 5 are arranged on the other diagonal. In other words, connection terminals 8a, 8b and connection terminals 8c, 8d are arranged in a staggered pattern on one side (bottom surface) of coil component 1.

[0020] Since the first wire 4 and the second wire 5 are wound around the body 2a in opposite directions, arranging the connection terminals 8a to 8d in a staggered pattern eliminates the need for the first wire 4 and the second wire 5 to cross at the point where they are heat-sealed to the connection terminals 8a to 8d. If the first wire 4 and the second wire 5 were arranged in the same alignment in the width direction, attempting to heat-seal the first wire 4 and the second wire 5 to the connection terminals 8a to 8d to prevent the coil winding from loosening would cause the first wire 4 and the second wire 5 to cross. When the first wire 4 and the second wire 5 cross, they may rub against each other, causing the insulation to peel off and potentially resulting in a short circuit between the first wire 4 and the second wire 5.

[0021] When heat-sealing the first wire 4 and second wire 5 to the connection terminals 8a to 8d while arranging them so that they are aligned in the width direction, if one attempts to bend the first wire 4 and second wire 5 in the short direction of the first flange 2b and second flange 2c after they have crossed in order to prevent the first wire 4 and second wire 5 from crossing, there is a possibility that the coil winding will loosen or the wires will break due to being forcibly bent during heat sealing. In other words, if the connection terminals 8a to 8d are not arranged in a staggered pattern, it is difficult to heat-seal the ends of the first wire 4 and second wire 5 to the connection terminals 8a to 8d in a direction perpendicular to the longitudinal direction of the first flange 2b and second flange 2c (the short direction of the first flange 2b and second flange 2c), as shown in Figure 3.

[0022] Furthermore, when the first wire 4 is crimped into the recess 7a formed in the first flange portion 2b, and the second wire 5 is crimped across it into the recess 7a formed in the first flange portion 2b, the crimping work is performed in a narrow space, making it difficult to manufacture the coil component 1. However, by arranging the connection terminals 8a to 8d in a staggered pattern as shown in Figure 3, it is not necessary to cross the first wire 4 and the second wire 5 at the point where the connection terminals 8a to 8d are heat-crimped to the first wire 4 and the second wire 5, making it easier to manufacture the coil component 1. In addition, by eliminating the need to cross the first wire 4 and the second wire 5 at the point where the connection terminals 8a to 8d are heat-crimped to the first wire 4 and the second wire 5, it becomes possible to form a coil with thicker wires.

[0023] Next, the mounting terminals for mounting the coil component 1 onto the circuit board will be described. As shown in Figures 1 to 3, the first flange portion 2b and the second flange portion 2c provided on both sides of the bobbin 2 are provided with mounting terminals 6a (first mounting terminal) and 6b (second mounting terminal) for electrically connecting to the first wire 4 and mounting to the circuit board, and mounting terminals 6c (third mounting terminal) and 6d (fourth mounting terminal) for electrically connecting to the second wire 5 and mounting to the circuit board. Specifically, the first flange portion 2b is provided with mounting terminals 6a and 6c, and the second flange portion 2c is provided with mounting terminals 6b and 6d. The surfaces on the first flange portion 2b and the second flange portion 2c on which each mounting terminal 6a to 6d is provided are one surface (bottom surface) of the coil component 1.

[0024] Mounting terminal 6a is formed on one surface of the first flange portion 2b and is electrically connected to a connection terminal 8a that connects to one end of the first wire 4. Mounting terminal 6b is formed on one surface of the second flange portion 2c and is electrically connected to a connection terminal 8b that connects to the other end of the first wire 4. Mounting terminal 6c is formed on one surface of the first flange portion 2b and is electrically connected to a connection terminal 8c that connects to one end of the second wire 5. Mounting terminal 6d is formed on one surface of the second flange portion 2c and is electrically connected to a connection terminal 8d that connects to the other end of the second wire 5.

[0025] As shown in Figure 3, the mounting terminals 6a and 6c formed on the first flange portion 2b are separated by the bottom surface 70 (second bottom surface) of the recess 7a and are not electrically connected. On the other hand, the mounting terminals 6b and 6d formed on the second flange portion 2c are connected via the recess 7b and are electrically connected, as shown in Figure 3.

[0026] The mounting terminals 6a to 6d can be formed, for example, by applying Ag paste to one surface of the first flange portion 2b and the second flange portion 2c using a dip method. When forming the mounting terminals 6a to 6d using the dip method, by adjusting the depth of the recesses 7a and 7b, it is possible to electrically connect mounting terminals 6b and 6d while keeping mounting terminals 6a and 6c disconnected.

[0027] As shown in FIG. 1, the recess 7a has a bottom surface with two steps of different depths. Specifically, the recess 7a has a bottom surface with a depth D1 (the bottom surface 70 (the second bottom surface) shown in FIG. 3) and a bottom surface with a depth D2 (<D1) (the bottom surfaces 71a and 71c (the first bottom surfaces) shown in FIG. 3) that form the connection terminals 8a and 8c. When applying Ag paste to the surface of the first flange portion 2b forming the recess 7a by the dip method, even if the coil component 1 is dipped in the Ag paste to such an extent that the Ag paste is applied to the bottom surfaces 71a and 71c, the bottom surface 70 deeper than the bottom surfaces 71a and 71c is not coated with the Ag paste. In addition, when one end of the first wire 4 is crushed and pressed against the connection terminal 8a and one end of the second wire 5 is crushed and pressed against the connection terminal 8c by thermocompression bonding, the depth D1 is preferably deeper than half of the wire diameters of the first wire 4 and the second wire 5. By setting the depth D1 in this way, it becomes difficult for the wire to protrude from the mounting terminal surface (the bottom surface 70), and mounting defects are less likely to occur.

[0028] On the other hand, as shown in FIG. 2, the recess 7b has a single-step bottom surface. Specifically, the recess 7b has a bottom surface with a depth D3 (=D2) that forms the connection terminals 8b and 8d. When applying Ag paste to the surface of the second flange portion 2c forming the recess 7b by the dip method, since it is dipped to such an extent that the Ag paste is applied to the bottom surfaces 71a and 71c, the Ag paste is applied to the entire bottom surface of the recess 7b having a similar depth. In addition, when the other end of the first wire 4 is crushed and pressed against the connection terminal 8b and the other end of the second wire 5 is crushed and pressed against the connection terminal 8d by thermocompression bonding, the depth D3 is preferably deeper than half of the wire diameters of the first wire 4 and the second wire 5. The depth D3 only needs to be smaller than the depth D1 and may be different from the depth D2.

[0029] In this way, the mounting terminals 6a to 6d and the connection terminals 8a to 8d can be formed simultaneously, and in the actual product, they are integrated electrodes. However, in the present disclosure, the electrodes at the portions where the wires are connected are defined as the connection terminals. <​​Coil component 1 achieves a three-terminal coil component by electrically connecting mounting terminals 6b and 6d via recess 7b, rather than electrically connecting mounting terminals 6a and 6c at the bottom surface 70 of recess 7a. Therefore, coil component 1 does not require electrical connection of mounting terminals 6b and 6d on the circuit board side.

[0031] Figure 4 is a plan view of a substrate 10 on which a coil component 1 according to Embodiment 1 is mounted. When the coil component 1 is mounted, the substrate 10 has land electrodes 11a for electrically connecting to mounting terminal 6a, 11b for electrically connecting to mounting terminal 6b, 11c for electrically connecting to mounting terminal 6c, and 11d for electrically connecting to mounting terminal 6d. By making the land electrodes 11a to 11d on the substrate 10 four terminals, and the mounting terminals 6a to 6d connected to these land electrodes 11a to 11d also four terminals, the occurrence of mounting defects due to differences in the size of the land electrodes (for example, chip popping (Manhattan phenomenon)) can be reduced. When the substrate 10 on which the coil component 1 is mounted constitutes a filter circuit, as will be described later, land electrode 11a is connected to the input wiring, land electrode 11c is connected to the output wiring, and a capacitor is connected to at least one of land electrodes 11b and 11d.

[0032] Next, the filter circuit 100 including the coil component 1 will be described. Figure 5 is a circuit diagram of the filter circuit 100 according to Embodiment 1. Specifically, the filter circuit 100 is an EMI removal filter circuit and is a third-order T-type LC filter circuit. In this disclosure, the configuration of the filter circuit 100 is described using a third-order T-type LC filter circuit, but the same configuration can be applied to a fifth-order T-type LC filter circuit or a higher-order T-type LC filter circuit. As shown in Figure 5, the filter circuit 100 includes the coil component 1 and the capacitor C1.

[0033] Coil component 1 includes mounting terminal 6a which serves as an input terminal, mounting terminal 6c which serves as an output terminal, mounting terminals 6b and 6d which serve as intermediate terminals, a first coil L1, and a second coil L2. Note that coil component 1 may also have mounting terminal 6c as the input terminal and mounting terminal 6a as the output terminal.

[0034] As shown in Figure 5, capacitor C1 is connected in series between the intermediate terminals 6b and 6d and the ground electrode (GND). While one capacitor C1 is sufficient, a circuit configuration with two capacitors connected in series is also possible, especially considering applications such as installation in a vehicle.

[0035] Note that capacitor C1 may be a multilayer ceramic capacitor primarily composed of BaTiO3 (barium titanate), a multilayer ceramic capacitor primarily composed of other materials, or even a non-multilayer ceramic capacitor such as an aluminum electrolytic capacitor.

[0036] The capacitor C1 connected to the coil component 1 has an inductor L3 as a parasitic inductance (equivalent series inductance (ESL)). Therefore, the filter circuit 100 is equivalent to a circuit configuration in which the inductor L3 is connected in series with the capacitor C1, as shown in Figure 5.

[0037] In addition to capacitor C1, the first coil L1 and the second coil L2 are connected to mounting terminals 6b and 6d. The first coil L1 and the second coil L2 are magnetically coupled, generating a negative inductance component (mutual inductance M). This negative inductance component can be used to cancel out the parasitic inductance (inductor L3) of capacitor C1, thereby making the inductance component of capacitor C1 appear smaller. In Figure 5, the equivalent circuit is shown with a mutual inductance M(-M) to cancel out inductor L3 connected in series with capacitor C1, and mutual inductance M(+M) added to each of the first coil L1 and the second coil L2.

[0038] The filter circuit 100, which consists of a capacitor C1, a first coil L1, and a second coil L2, can improve the noise suppression effect in the high-frequency band by canceling out the parasitic inductance of the capacitor C1 with the negative inductance component due to the mutual inductance M between the first coil L1 and the second coil L2.

[0039] Furthermore, the characteristics of the coil component 1 will be explained. Figure 6 is a diagram illustrating the relationship between the width of the body portion 2a and the width of the recess 7b in the coil component 1. As shown in Figure 6, it is preferable that the width W2 of the recess 7b formed in the second flange portion 2c of the coil component 1 is shorter than the width W1 of the body portion 2a of the bobbin 2. By making the width W2 of the recess 7b shorter than the width W1 of the body portion 2a, it is possible to maintain a high tension on the wire that has started to be wound from the first flange portion 2b. It is preferable that the width W2 of the recess 7b is shortened inward by the thickness of one wire from the end of the width W1 of the body portion 2a. This makes it possible to maintain a higher tension on the wire while securing a wider width W2 for the crimping space.

[0040] As shown in Figure 3, the parts that are heat-sealed to the first wire 4 and the second wire 5 at the bottom surfaces 71a and 71c of the recess 7a are the connection terminals 8a and 8c. Therefore, connection terminal 8a is provided in the area of ​​the bottom surface 71a, and connection terminal 8c is provided in the area of ​​the bottom surface 71c. On the other hand, the parts that are heat-sealed to the first wire 4 and the second wire 5 at the bottom surface of the recess 7a are the connection terminals 8b and 8d, so the area in which connection terminals 8a and 8c can be provided is wide. Connection terminals 8b and 8d are formed in the same recess 7b formed in the second flange portion 2c, but it is sufficient that the connection terminals 8b and 8d are positioned so that at least the first wire 4 and the second wire 5 do not intersect.

[0041] More preferably, the connection terminals 8b and 8d are arranged relative to each other within a range that does not exceed halfway in the width direction within the recess 7b formed in the second flange portion 2c. Figure 7 is a diagram illustrating the range of connection terminals 8b and 8d that connect the ends of the wires in the coil component 1. As shown in Figure 7, the connection terminals 8b and 8d may be arranged diagonally within a range that does not exceed the center of the recess 7b. In other words, the connection terminal 8b that connects to the first wire 4 is arranged within a range of half the width W2 (W2 / 2) of the recess 7b on the opposite side. As a result, when two wires are heat-sealed at different times, such as heat-sealing the first wire 4 to the connector terminal 8b and then heat-sealing the second wire 5 to the connector terminal 8d, heat-sealing one wire within half the width W2 of the recess 7b (W2 / 2) ensures that the wire to be heat-sealed later is reliably heat-sealed to the recess 7b.

[0042] As described above, in the coil component 1 according to Embodiment 1, on the surface of the coil component 1 provided with recesses 7a and 7b, the connection terminal 8a is positioned diagonally to the connection terminal 8b, and the connection terminal 8c is positioned diagonally to the connection terminal 8d. This eliminates the need to cross the first wire 4 and the second wire 5 and connect them to the connection terminals 8a to 8d provided in the recesses 7a and 7b, making it easier to manufacture the coil component 1.

[0043] In coil component 1, the second flange portion 2c electrically connects the two terminals, mounting terminal 6b and mounting terminal 6d. However, a recess 7b is provided to raise the portion where the connecting terminals 8b and 8d are formed above the mounting surface, thereby preventing solder from adhering to that portion and reducing the occurrence of mounting defects (for example, chip lifting (Manhattan phenomenon)).

[0044] When the first wire 4 and the second wire 5 are heat-compressed to the connection terminals 8a to 8b, the heat-compressed area oxidizes, reducing the wettability of the solder. Therefore, by heat-compressing the first wire 4 to the connection terminal 8b and the second wire 5 to the connection terminal 8b near the wall surface of the recess 7b, the spread of solder wetting can be stopped at the heat-compressed area when the coil component 1 is mounted on the circuit board 10. As a result, when the coil component 1 is mounted on the circuit board 10 with solder, the size of the solder adhering to each of the mounting terminals 6a to 6d can be kept the same. Furthermore, by utilizing the fact that the wettability of the solder is reduced at the heat-compressed area, it is possible to avoid unnecessary solder adhesion when the coil component 1 is mounted on the circuit board 10 with solder.

[0045] In the coil component 1, when it is mounted on the circuit board 10 with solder, a deep recess 7a may be provided in the first flange portion 2b so that the mounting terminals 6a and 6c are not electrically connected, while the recess 7b provided in the second flange portion 2c may be made shallower, and the electrical connection between the mounting terminals 6b and 6d may be reinforced with solder.

[0046] <Embodiment 2> In the coil component 1 according to Embodiment 1, the configuration described was that the two terminals, mounting terminal 6b and mounting terminal 6d, are electrically connected at the second flange portion 2c to form a single terminal. However, the two terminals, mounting terminal 6b and mounting terminal 6d, may not be electrically connected on the coil component 1 side, but rather on the substrate 10 side. Below, a coil component according to Embodiment 2, in which the two terminals are not electrically connected on the coil component side, will be described. Figure 8 is a perspective view of the coil component 1A according to Embodiment 2. Figure 9 is a perspective view of the coil component 1A according to Embodiment 2 from a different direction. Figure 10 is a bottom view of the coil component 1A according to Embodiment 2. When the X-axis, Y-axis, and Z-axis are defined as shown in Figures 8 to 10, the X-axis direction is the length direction of the coil component 1A, the Y-axis direction is the width direction of the coil component 1A, and the Z-axis direction is the height direction of the coil component 1A. In the coil component 1A according to Embodiment 2, the same reference numerals are used for components that are the same as those in the coil component 1 according to Embodiment 1 shown in Figures 1 to 3, and detailed explanations will not be repeated.

[0047] The coil component 1A includes a bobbin 2, a first wire 4, and a second wire 5. The bobbin 2 has a body portion 2a around which the wire is wound, and a first flange portion 2b and a second flange portion 2c provided at both ends of the body portion 2a.

[0048] In coil component 1A, the first wire 4 and the second wire 5 are wound around the body portion 2a in opposite directions to form two coils. Furthermore, in coil component 1A, the first wire 4 is wound once around the body portion 2a to form the first coil L1, and the second wire 5 is wound once around the body portion 2a to form the second coil L2. Note that winding the first wire 4 and second wire 5 once is just an example; multiple windings are also possible.

[0049] To stabilize the coupling coefficient and maintain a constant distance between wires, the coil component 1A has connection terminals 8a to 8d provided in recesses 7a and 7c formed in the flange portion to connect and fix the first wire 4 and the second wire 5. Specifically, one end of the first wire 4 is connected to the connection terminal 8a (first connection terminal) by thermocompression in the recess 7a formed in the first flange portion 2b. The other end of the first wire 4 is connected to the connection terminal 8b (second connection terminal) by thermocompression in the recess 7c formed in the second flange portion 2c. As shown in Figure 10, on the surface (bottom surface) of the coil component 1A with recesses 7a and 7c, the connection terminal 8a is diagonally opposite to the connection terminal 8b. Furthermore, the method of connecting the end of the first wire 4 to the connection terminals 8a and 8b is not limited to thermocompression, but may also be, for example, laser welding.

[0050] Furthermore, one end of the second wire 5 is connected to the connection terminal 8c (third connection terminal) by thermocompression in a recess 7a formed in the first flange portion 2b. The other end of the second wire 5 is connected to the connection terminal 8d (fourth connection terminal) by thermocompression in a recess 7c formed in the second flange portion 2c. As shown in Figure 10, on the surface (bottom surface) of the coil component 1A where the recesses 7a and 7c are provided, the connection terminal 8c is located diagonally opposite to the connection terminal 8d. Also, the method of connecting the end of the second wire 5 to the connection terminals 8c and 8d is not limited to thermocompression, but may be, for example, laser welding.

[0051] The mounting terminal 6a is formed on one surface of the first flange portion 2b and is electrically connected to a connection terminal 8a that connects to one end of the first wire 4. Further, the mounting terminal 6c is formed on one surface of the first flange portion 2b and is electrically connected to a connection terminal 8c that connects to one end of the second wire 5. The mounting terminal 6a and the mounting terminal 6c formed on the first flange portion 2b are separated by the bottom surface 70 (second bottom surface) of the recess 7a and are not electrically connected, as shown in FIG. 10.

[0052] On the other hand, the mounting terminal 6b is formed on one surface of the second flange portion 2c and is electrically connected to a connection terminal 8b that connects to the other end of the first wire 4. Further, the mounting terminal 6d is formed on one surface of the second flange portion 2c and is electrically connected to a connection terminal 8d that connects to the other end of the second wire 5. The mounting terminal 6b and the mounting terminal 6d formed on the second flange portion 2c are separated by the bottom surface 72 (fourth bottom surface) of the recess 7c and are not electrically connected, as shown in FIG. 10.

[0053] As shown in FIG. 8, the recess 7a has two bottom surfaces with different depths. Specifically, the recess 7a has a bottom surface with a depth D1 (the bottom surface 70 (second bottom surface) shown in FIG. 10) and a bottom surface with a depth D2 (<D1) for forming the connection terminals 8a and 8c (the bottom surfaces 71a and 71c (first bottom surfaces) shown in FIG. 10). When applying Ag paste by the dip method to the surface of the first flange portion 2b that forms the recess 7a, even if the coil component 1A is dipped in the Ag paste to such an extent that the Ag paste is applied to the bottom surfaces 71a and 71c, the bottom surface 70, which is deeper than the bottom surfaces 71a and 71c, is not coated with the Ag paste.

[0054] Further, as shown in FIG. 9, the depression 7c has two bottom surfaces with different depths. Specifically, the depression 7c has a bottom surface with a depth D1 (the bottom surface 72 (the fourth bottom surface) shown in FIG. 10) and a bottom surface with a depth D2 (<D1) for forming the connection terminals 8b and 8d (the bottom surfaces 71b and 71d (the third bottom surface) shown in FIG. 10). When applying Ag paste by the dip method to the surface of the second flange portion 2c where the depression 7c is formed, even if the coil component 1A is dipped in the Ag paste to such an extent that the Ag paste is applied to the bottom surfaces 71b and 71d, the bottom surface 72 deeper than the bottom surfaces 71b and 71d is not coated with the Ag paste. Although the bottom surface 70 of the depression 7a and the bottom surface 72 of the depression 7c have been described as having the same depth D1, they may have different depths. Also, although the bottom surfaces 71a and 71c of the depression 7a and the bottom surfaces 71b and 71d of the depression 7c have been described as having the same depth D2, they may have different depths.

[0055] [[ID=④]]The coil component 1A realizes a four-terminal coil component by not electrically connecting the mounting terminals 6a and 6c at the bottom surface 70 of the depression 7a and not electrically connecting the mounting terminals 6b and 6d at the bottom surface 72 of the depression 7c. Therefore, when the coil component 1A is used in the filter circuit 100, it is necessary to electrically connect the mounting terminals 6b and 6d on the substrate side.

[0056] FIG. 11 is a plan view of a substrate 10A on which the coil component 1A according to the second embodiment is mounted. On the substrate 10A, when the coil component 1A is mounted, land electrodes 11a for electrically connecting to the mounting terminal 6a, land electrodes 11b for electrically connecting to the mounting terminal 6b, land electrodes 11c for electrically connecting to the mounting terminal 6c, and land electrodes 11d for electrically connecting to the mounting terminal 6d are respectively formed. On the substrate 10A, a wiring 12 is provided to electrically connect the land electrode 11b and the land electrode 11d. By electrically connecting the land electrode 11b and the land electrode 11d with the wiring 12, the mounting terminals 6b and 6d can be commonly connected to one electrode of the capacitor C1 as intermediate terminals.

[0057] It should be noted that in the translation of the fourth paragraph, there was a number "④" in the original Japanese text which might be an error. I translated it as "④" in the English text for the sake of consistency with the original content. If this is a misprint in the original, please correct it in the source material.Although it was explained that the substrate 10A electrically connects land electrodes 11b and 11d with wiring 12, land electrodes 11b and 11d and wiring 12 may be formed as a single land electrode. Since the two terminals of the coil component 1A are electrically connected on the substrate 10A side, there is no need to worry about the orientation of the coil component 1A relative to the substrate 10A, and there is no need to attach identification marks when manufacturing the coil component 1A. In other words, the coil component 1A may have its mounting terminal 6a connected to land electrode 11d and its mounting terminal 6c connected to land electrode 11b, and the mounting terminal 6a and mounting terminal 6c may be electrically connected on the substrate 10A side.

[0058] When the substrate 10A electrically connects the land electrode 11b and the land electrode 11d with wiring 12, the wiring 12 may be covered with insulating solder resist, the height of the land electrode 11b and the land electrode 11d may be made higher than the height of the wiring 12, or the wiring 12 may be provided inside the substrate 10A or on the back surface of the substrate 10A. As a result, when mounting the coil component 1A on the substrate 10A, the sizes of the mounting terminals 6a to 6d of the coil component 1A and the land electrodes 11a to 11d can be kept the same, thereby reducing chip lifting of the coil component 1A mounted on the substrate 10A.

[0059] <Example 1> The substrate 10A shown in Figure 11 has a configuration in which land electrodes 11b and 11d are electrically connected by wiring 12. However, a coil component 1 may be mounted on which mounting terminals 6b and 6d are electrically connected on the coil component 1 side. By mounting the coil component 1 on the substrate 10A, mounting terminals 6b and 6d can be electrically connected on both the coil component 1 side and the substrate 10A side, thereby providing redundancy.

[0060] <Modification 2> The recess 7a formed in the first flange portion 2b has two bottom surfaces of different depths, as shown in Figure 1. Figure 12 is a diagram illustrating the shape of the recess 7a formed in the flange portion of the coil component 1. The recess 7a has a deep bottom surface 70 (second bottom surface) and shallow bottom surfaces 71a, 71c (first bottom surface).

[0061] The deep bottom surface 70 is not coated with electrode material (for example, Ag paste), but the shallow bottom surfaces 71a and 71c are coated with electrode material. The first wire 4 and the second wire 5 are heat-pressed to the bottom surfaces 71a and 71c where the electrode material is applied, forming connection terminals 8a and 8c. The location where the first wire 4 and the second wire 5 are heat-pressed may be the bottom surfaces 71a and 71c, or the wall surface of the recess 7a adjacent to the bottom surfaces 71a and 71c.

[0062] When electrode material is applied to the bottom surfaces 71a and 71c using a dip method, electrode material is also applied to the areas that will become mounting terminals 6a and 6c. Therefore, connection terminal 8a and mounting terminal 6a are electrically connected, and connection terminal 8c and mounting terminal 6c are electrically connected. However, since electrode material is not applied to the bottom surface 70, mounting terminals 6a and 6c are not electrically connected.

[0063] Thus, when forming the mounting terminals 6a, 6c and connection terminals 8a, 8c using the dip method, it is preferable that the recess 7a has two bottom surfaces of different depths, as shown in Figure 12. However, when forming the mounting terminals 6a, 6c and connection terminals 8a and 8c using a method other than the dip method, such as the sputter method, a recess with a single bottom surface is sufficient.

[0064] Figure 13 illustrates a different shape of recess 7d formed in the flange portion of the coil component 1. The recess 7d formed in the first flange portion 2b simply has a single-step bottom surface 75, as shown in Figure 13. The bottom surface 75 of recess 7d may be the same depth as the bottom surface 70 of recess 7a, or it may be of a different depth.

[0065] When forming connection terminals 8a and 8c on the bottom surface 75 using the sputtering method, a portion of the bottom surface 75 can be left uncoated with electrode material, allowing connection terminals 8a and 8c to be formed in such a way that they are not electrically connected. Electrode material is applied to the portions that will become mounting terminals 6a and 6c using either the dip or sputtering method to form mounting terminal 6a, which is electrically connected to connection terminal 8a, and mounting terminal 6c, which is electrically connected to connection terminal 8c. In this way, by forming connection terminals 8a and 8c using the sputtering method, even with a simple single-stage bottom surface 75, a portion of the bottom surface 75 can be left uncoated with electrode material, preventing mounting terminals 6a and 6c from being electrically connected.

[0066] Furthermore, the configuration of the recess 7d shown in Figure 13 can also be applied to the recess 7c formed in the second flange portion 2c shown in Figure 9.

[0067] <Variation 3> When coil component 1,1A is applied to a filter circuit used in a power line, for example, it is expected that a current of approximately 3A or more will flow through the first wire 4 and the second wire 5, so the DC resistance of the wires needs to be approximately 20mΩ or less. For this reason, it is preferable that the wire diameter of the first wire 4 and the second wire 5 be approximately 100μm or more. Coil component 1,1A heat-compresses the first wire 4 and the second wire 5 in a recess, so it is preferable that the depth of the recess is greater than the thickness of the wires after they have been compressed, even though the wire diameter is approximately 100μm or more. For example, if the wire diameter of the first wire 4 and the second wire 5 is compressed by half during heat compression, the depth of the recess should be greater than approximately 50μm.

[0068] <Mode> (1) A coil component having a first coil and a second coil, A bobbin having a body portion around which the wire is wound, and a first flange portion and a second flange portion provided at both ends of the body portion, A first wire is wrapped around the body to form the first coil, The device comprises a second wire that is wrapped around the body in the opposite direction to the first wire, forming a second coil, Bobbin is Multiple mounting terminals are formed on one surface of the first flange and the second flange for mounting coil components onto a substrate, It includes a plurality of connecting terminals formed on one surface of the first flange and the second flange for connecting the ends of the first wire and the second wire, Among the multiple mounting terminals, The first mounting terminal is formed on one surface of the first flange and is electrically connected to a first connecting terminal that connects to one end of the first wire. The second mounting terminal is formed on one surface of the second flange and is electrically connected to the second connecting terminal which connects to the other end of the first wire. The third mounting terminal is formed on one surface of the first flange and is electrically connected to the third connecting terminal, which connects to one end of the second wire. The fourth mounting terminal is formed on one side of the second flange and is electrically connected to the fourth connecting terminal, which connects to the other end of the second wire. A coil component having recesses on one of the first and second flange surfaces, wherein the first connecting terminal is located diagonally to the second connecting terminal, and the third connecting terminal is located diagonally to the fourth connecting terminal.

[0069] (2) The coil component described in (1), wherein the second and fourth connecting terminals are formed in the same recess formed in the second flange and are arranged so that the first wire and the second wire do not cross.

[0070] (3) The coil component described in (1) or (2), wherein the width of the recess formed in the second flange portion is shorter than the width of the body portion.

[0071] (4) A coil component as described in any one of items (1) to (3), wherein the second connecting terminal is connected to the first wire in a range up to halfway in the direction of the width of the recess formed in the second flange, The fourth connector is connected to the second wire up to halfway along the width of the recess formed in the second flange.

[0072] (5) A coil component as described in any one of items (1) to (4), wherein the second mounting terminal and the fourth mounting terminal are electrically connected.

[0073] (6) A coil component according to any one of items (1) to (5), wherein the depth of the recess formed in the second flange is different from the depth of the recess formed in the first flange.

[0074] (7) A coil component according to any one of items (1) to (6), wherein the recess formed in the first flange portion has a first bottom surface at a first depth and a second bottom surface at a second depth greater than the first depth, The first mounting terminal and the third mounting terminal are located on the first bottom surface.

[0075] (8)(7) The coil component described above, wherein the first depth is greater than half the diameter of the first and second wires.

[0076] (9) A coil component according to any one of items (1) to (8), wherein the first mounting terminal and the third mounting terminal are provided on part of the wall and bottom surface of the recess formed in the first flange.

[0077] (10) A coil component as described in any one of items (1) to (9), wherein the number of turns of the body portion of the first wire and the number of turns of the body portion of the second wire are both 1 turn.

[0078] (11) A coil component as described in any one of items (1) to (10), wherein the first mounting terminal, second mounting terminal, third mounting terminal and fourth mounting terminal are all provided on the same side of the bobbin.

[0079] (12) The filter circuit of this disclosure includes the coil component described in any one of (1) to (11), A circuit board on which coil components are mounted, The circuit board is mounted and includes a capacitor, one of which is electrically connected to the second and fourth mounting terminals of the coil component.

[0080] (13)(12) The filter circuit, wherein the substrate has land electrodes for electrically connecting to the terminals of the first mounting terminal, the second mounting terminal, the third mounting terminal and the fourth mounting terminal, A land electrode for electrically connecting to the second mounting terminal and a land electrode for electrically connecting to the fourth mounting terminal are electrically connected.

[0081] (14) Another filter circuit of the present disclosure includes the coil component described in (5), A circuit board on which coil components are mounted, The circuit board is mounted, and the capacitor is electrically connected to at least one terminal of the second mounting terminal and the fourth mounting terminal of the coil component, and to one electrode.

[0082] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of this disclosure is indicated by the claims rather than by the foregoing description, and all modifications within the meaning and scope of the claims are intended to be included. [Explanation of symbols]

[0083] 1,1A coil component, 2 bobbin, 2a body, 2b first flange, 2c second flange, 4 first wire, 5 second wire, 6a~6d mounting terminals, 8a~8d connection terminals, 10,10A circuit board, 100 filter circuit.

Claims

1. A coil component having a first coil and a second coil, A bobbin having a body portion around which the wire is wound, and a first flange portion and a second flange portion provided at both ends of the body portion, A first wire is wrapped around the body portion to form the first coil, A second wire is wound around the body in the opposite direction to the first wire to form the second coil, and the second wire is also included. The bobbin mentioned above is A plurality of mounting terminals are formed on one surface of the first flange and the second flange for mounting the coil component onto the substrate, The first flange portion and the second flange portion include a plurality of connecting terminals formed on one surface of the first flange portion for connecting the ends of the first wire and the second wire, Among the aforementioned multiple mounting terminals, The first mounting terminal is formed on one surface of the first flange and is electrically connected to a first connecting terminal that connects to one end of the first wire. The second mounting terminal is formed on one surface of the second flange and is electrically connected to a second connecting terminal that connects to the other end of the first wire. The third mounting terminal is formed on one surface of the first flange and is electrically connected to a third connecting terminal that connects to one end of the second wire. The fourth mounting terminal is formed on one surface of the second flange and is electrically connected to the fourth connecting terminal which connects to the other end of the second wire. On the surface of the coil component having a recess provided on one of the first flange portion and the second flange portion, the first connecting terminal is located diagonally to the second connecting terminal, and the third connecting terminal is located diagonally to the fourth connecting terminal. The recess formed in the first flange portion has a first bottom surface at a first depth and a second bottom surface at a second depth that is deeper than the first depth. The first mounting terminal and the third mounting terminal are coil components provided on the first bottom surface.

2. The coil component according to claim 1, wherein the second and fourth connecting terminals are formed in the same recess formed in the second flange and are arranged so that the first wire and the second wire do not cross.

3. The coil component according to claim 1 or claim 2, wherein the width of the recess formed in the second flange portion is shorter than the width of the body portion.

4. The second connecting terminal is connected to the first wire in a range up to halfway in the direction of the width of the recess formed in the second flange, The coil component according to claim 1 or 2, wherein the fourth connecting terminal is connected to the second wire in a range up to halfway in the direction of the width of the recess formed in the second flange.

5. The coil component according to claim 1 or claim 2, wherein the second mounting terminal and the fourth mounting terminal are electrically connected.

6. The coil component according to claim 1 or claim 2, wherein the depth of the recess formed in the second flange portion is different from the depth of the recess formed in the first flange portion.

7. The coil component according to claim 1, wherein the first depth is deeper than half the wire diameter of the first wire and the second wire.

8. The coil component according to claim 1 or claim 2, wherein the first mounting terminal and the third mounting terminal are provided on a portion of the wall and bottom surface of the recess formed in the first flange.

9. The coil component according to claim 1 or claim 2, wherein the number of turns of the first wire in the body portion and the number of turns of the second wire in the body portion are 1 turn.

10. The coil component according to claim 1 or claim 2, wherein the first mounting terminal, the second mounting terminal, the third mounting terminal, and the fourth mounting terminal are all provided on the same surface of the bobbin.

11. The coil component according to claim 1 or claim 2, A circuit board on which the aforementioned coil component is mounted, A filter circuit comprising a capacitor mounted on the substrate, the second mounting terminal and the fourth mounting terminal of the coil component, and one of its electrodes electrically connected to the capacitor.

12. The substrate has land electrodes for electrically connecting to each of the terminals of the first mounting terminal, the second mounting terminal, the third mounting terminal, and the fourth mounting terminal. The filter circuit according to claim 11, wherein the land electrode for electrically connecting to the second mounting terminal and the land electrode for electrically connecting to the fourth mounting terminal are electrically connected.

13. The coil component described in claim 5, A circuit board on which the aforementioned coil component is mounted, A filter circuit comprising a capacitor mounted on the substrate, wherein at least one terminal of the second mounting terminal and the fourth mounting terminal of the coil component is electrically connected to one electrode.

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