Laminated coil components

Abstract

This invention provides a laminated coil component that improves the Q factor by reducing the DC resistance and eddy current losses of the coil. [Solution] The laminated coil component 1 comprises a base body 2 formed by stacking a plurality of layers 11 in a predetermined stacking direction, a coil 3 disposed inside the base body 2, an external electrode 4 disposed on the outer surface of the base body 2, and a lead conductor 5 that electrically connects the coil 3 and the external electrode 4. The lead conductor 5 has a plurality of end conductors 12 that extend between the outer surface of the base body 2 and the coil 3 at different positions in the stacking direction, and a plurality of connecting conductors 13 that linearly connect each of the plurality of end conductors 12 to the end of the coil 3.

Description

Technical Field

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[0001] The present disclosure relates to a multilayer coil component.

Background Art

[0002] As a conventional multilayer coil component, there is, for example, an inductor component described in Patent Document 1. This conventional multilayer coil component includes a body formed by laminating a plurality of layers, a coil provided inside the body, and external electrodes provided on the outer surface of the body. The coil inside the body is composed of a plurality of coil conductors electrically connected to each other. The ends of the coil are drawn out to the outer surface of the body by lead conductors and are electrically connected to the external electrodes.

[0003] Also, for example, in the multilayer coil component described in Patent Document 2, from the viewpoint of reducing the DC resistance of the coil, the coil is provided with a plurality of ends (first end to third end). When viewed from the lamination direction of the body, at least a part of the first end and the third end overlap each other. Also, the first end and the third end have a region that does not overlap with the second end when viewed from the lamination direction of the body. In this multilayer coil component, an increase in the size of the component is avoided, and the current path difference between the ends is suppressed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] This disclosure was made to solve the above-mentioned problems and aims to provide a laminated coil component that improves the Q value by reducing the DC resistance and eddy current loss of the coil. [Means for solving the problem]

[0007] The gist of this disclosure is as follows:

[0008] [1] A laminated coil component comprising: a base body formed by laminating a plurality of layers in a predetermined lamination direction; a coil disposed inside the base body; an external electrode disposed on the outer surface of the base body; and a lead conductor electrically connecting the coil and the external electrode, wherein the lead conductor has a plurality of end conductors extending between the outer surface of the base body and the coil at different positions in the lamination direction, and a plurality of connecting conductors that linearly connect each of the plurality of end conductors to the end of the coil.

[0009] In this laminated coil component, the coil, which is located inside the main body, is led out to the outer surface of the main body via multiple paths by lead conductors. This reduces the DC resistance of the coil. Furthermore, in this laminated coil component, the multiple connecting conductors that connect each of the multiple end conductors to the ends of the coil are in a straight line. In this way, the absence of bends in the connecting conductors reduces eddy current losses in the lead conductors. As a result, this laminated coil component improves the Q factor by reducing the DC resistance of the coil and reducing eddy current losses.

[0010] [2] The laminated coil component according to [1], wherein, when viewed from the stacking direction, the shape of the coil is circular, and each of the plurality of connecting conductors extends in the tangential direction of the coil. In this case, the circular coil and the end conductor can be connected by connecting conductors over a short distance. Therefore, eddy current losses when a circular coil is used can be sufficiently reduced.

[0011] [3] When viewed from the stacking direction, the shape of the coil is rectangular with arc-shaped corners, and the plurality of connecting conductors are composed of a first connecting conductor extending in the direction of the extension of the straight side of the coil and a second connecting conductor extending in the tangential direction of the corner of the coil, as described in [1]. In this case, the rectangular coil and the end conductor can be connected over a short distance by the connecting conductor. Therefore, eddy current loss when a rectangular coil is used can be sufficiently reduced.

[0012] [4] When viewed from the stacking direction, the shape of the coil is oval, having a pair of straight sides facing each other and a pair of arc-shaped sides connecting the ends of the pair of sides, and the plurality of connecting conductors are composed of a first connecting conductor extending in the direction of the extension of the straight sides of the coil and a second connecting conductor extending in the tangential direction of the arc-shaped sides of the coil, as described in [1]. In this case, the oval-shaped coil and the end conductors can be connected over a short distance by the connecting conductors. Therefore, eddy current loss when an oval-shaped coil is used can be sufficiently reduced.

[0013] [5] A laminated coil component according to any one of [1] to [4], wherein, when viewed from the lamination direction, the plurality of end conductors are parallel to each other. In this case, even if variations occur in the dimensions of the base material during chipping in the manufacturing process of the laminated coil component, variations in the length of the end conductors and variations in the spacing between end conductors on the outer surface of the base material can be suppressed. This makes it possible to suppress an increase in DC resistance due to excessive length of the end conductors and the occurrence of cracks caused by the proximity of end conductors to each other on the outer surface of the base material.

[0014] [6] A laminated coil component according to any one of [1] to [5], wherein the widths of the plurality of end conductors are equal when viewed from the lamination direction. In this case, even if variations occur in the dimensions of the base material during chipping in the manufacturing process of the laminated coil component, variations in the width of the end conductors between individual components and variations in the spacing between end conductors on the outer surface of the base material can be suppressed. This makes it possible to suppress an increase in DC resistance due to insufficient width of the end conductors and the occurrence of cracks caused by the proximity of end conductors to each other on the outer surface of the base material.

[0015] [7] A laminated coil component according to any one of [1] to [6], wherein, when viewed from the lamination direction, the length of one end of the end conductor connected to the inner line of the connecting conductor in the width direction and the length of the other end of the end conductor connected to the outer line of the connecting conductor in the width direction are different from each other. With such a configuration, the width of the end conductor responsible for electrical connection with the external electrode can be kept constant, while the coil and connecting conductor, whose width changes according to the design value of the inductance, can be connected to the end conductor at a gentle angle. This makes it possible to reduce the resistance between the external electrode and the end conductor, and to reduce the eddy current loss between the connecting conductor and the end conductor. [Effects of the Invention]

[0016] According to this disclosure, the Q factor is improved by reducing the DC resistance and losses of the coil. [Brief explanation of the drawing]

[0017] [Figure 1] This is a schematic perspective view of a laminated coil component according to one embodiment of the present disclosure. [Figure 2] Figure 1 is a schematic YZ cross-sectional view of a laminated coil component. [Figure 3] Figure 1 is a schematic XY cross-sectional view of the laminated coil component. [Figure 4] Figure 1 is a schematic exploded perspective view showing the layer configuration of the laminated coil component. [Figure 5]It is a schematic enlarged view of a main part showing the detailed configuration of the lead-out conductor of the multilayer coil component shown in FIG. 1. [Figure 6] It is a schematic enlarged view of a main part showing the connection part between the end conductor and the connection conductor in the embodiment. [Figure 7] (a) and (b) are schematic enlarged views of a main part showing the connection part between the end conductor and the connection conductor in the comparative example. [Figure 8] (a) and (b) are schematic enlarged views of a main part showing the connection part between the end conductor and the connection conductor in another comparative example. [Figure 9] It is a schematic YZ cross-sectional view of the multilayer coil component according to the modified example. [Figure 10] It is a schematic enlarged view of a main part showing the lead-out conductor of the multilayer coil component shown in FIG. 9. [Figure 11] It is a schematic YZ cross-sectional view of the multilayer coil component according to another modified example. [Figure 12] It is a schematic enlarged view of a main part showing the lead-out conductor of the multilayer coil component shown in FIG. 11.

Embodiments for Carrying Out the Invention

[0018] Hereinafter, a preferred embodiment of a multilayer coil component according to one aspect of the present disclosure will be described in detail with reference to the drawings.

[0019] FIG. 1 is a schematic perspective view of a multilayer coil component according to an embodiment of the present disclosure. FIG. 2 is a schematic YZ cross-sectional view of the multilayer coil component shown in FIG. 1, and FIG. 3 is a schematic XY cross-sectional view thereof. The multilayer coil component 1 shown in FIGS. 1 to FIG. 3 is a coil component applied to, for example, a high-frequency inductor, a bead inductor, a power inductor, etc. The multilayer coil component 1 is configured to include a base body 2, a coil 3, a pair of external electrodes 4 (4A, 4B), and a pair of lead-out conductors 5 (5A, 5B) as shown in FIG. 1.

[0020] The base body 2 has, for example, a rectangular parallelepiped shape. The rectangular parallelepiped shape includes a rectangular parallelepiped shape with chamfered corners and edges, and a rectangular parallelepiped shape with rounded corners and edges. The base body 2 is composed of a stack of multiple layers 11 (see Figure 4). The base body 2 can be formed by heat-treating a stack of multiple layers. There are no particular restrictions on the heat treatment temperature, but for example, it is around 850°C to 900°C.

[0021] Element 2 has electrical insulating properties. Element 2 is composed of, for example, a magnetic material. The magnetic material can be selected from, for example, Ni-Cu-Zn ferrite materials, Ni-Cu-Zn-Mg ferrite materials, Ni-Cu ferrite materials, or combinations thereof. The magnetic material may also contain Fe alloys, etc. Element 2 may also be composed of a non-magnetic material. The non-magnetic material can be selected from, for example, glass ceramic materials, dielectric materials, or combinations thereof.

[0022] The base body 2 has a pair of end faces 2a, 2b, a pair of side faces 2c, 2d, and a pair of main faces 2e, 2f. In this embodiment, side face 2d is the mounting surface (the surface facing other electronic components) when the laminated coil component 1 is mounted on other electronic components. The opposing directions of the main faces 2e, 2f are the stacking directions of the multiple layers that constitute the base body 2. For convenience, in the following description, the opposing direction of the main faces 2e, 2f (the stacking directions of the multiple layers) is referred to as the X direction, the opposing direction of the end faces 2a, 2b is referred to as the Y direction, and the opposing direction of the side faces 2c, 2d is referred to as the Z direction.

[0023] The external electrode 4 is a terminal electrode that electrically connects the coil 3 inside the main body 2 to other electronic components. The external electrodes 4A and 4B are arranged on the outer surface of the main body 2, spaced apart from each other. In this embodiment, the external electrode 4A is provided so as to cover the end face 2a, and the external electrode 4B is provided so as to cover the end face 2b. The external electrode 4A protrudes from the end face 2a to the side surfaces 2c, 2d and the main surfaces 2e, 2f, covering the portion of the side surfaces 2c, 2d on the end face 2a side, and the portion of the main surfaces 2e, 2f on the end face 2a side, respectively. The external electrode 4B protrudes from the end face 2b to the side surfaces 2c, 2d and the main surfaces 2e, 2f, covering the portion of the side surfaces 2c, 2d on the end face 2b side, and the portion of the main surfaces 2e, 2f on the end face 2b side, respectively.

[0024] The external electrode 4 is made of a metallic material such as copper, silver, gold, nickel, or chromium. The external electrode 4 can be formed, for example, by sintering a conductive paste containing the above metallic material. For example, the conductive paste can be applied by a dipping method, a printing method, a transfer method, etc. The surface of the external electrode 4 may be provided with a plating layer by electroplating or electroless plating. The plating layer may be, for example, a Ni plating layer, a Sn plating layer, or an Au plating layer. The plating layer may be a single layer or multiple layers.

[0025] Coil 3 is located inside the base body 2, as shown in Figures 2 and 3. Coil 3 is composed of multiple coil conductors 6 and multiple vias 7. The coil conductors 6 and vias 7 are made of conductive materials such as Ag and Pd. The coil conductors 6 are patterned on each of the multiple layers 11 (see Figure 4) by printing or other means. The coil conductors 6 are stacked in the X-axis direction by stacking the multiple layers 11. The vias 7 penetrate the base body portions located between adjacent coil conductors 6 in the stacking direction, electrically connecting adjacent coil conductors 6 in the stacking direction.

[0026] In this embodiment, as shown in Figure 2, the shape of the coil 3 when viewed from the X direction (stacking direction) is circular. In this embodiment, the coil 3 is a single winding of three coil conductors 6. The coil conductors 6 constituting the coil 3 are composed of coil conductors 6a to 6f formed in each of the multiple layers 11a to 11f, as shown in Figure 4.

[0027] In the example shown in Figure 4, the coil conductors 6a to 6c are patterned on layers 11a to 11c such that, when viewed from the X direction, they form half of the circumference on the end face 2b side of the coil 3. The coil conductors 6d to 6f are patterned on layers 11a to 11c such that, when viewed from the X direction, they form half of the circumference on the end face 2a side of the coil 3. Although not shown, a protective layer may be laminated on the outer layer of layer 11a or the outer layer of layer 11f, on which no internal conductors such as coil conductors are formed (a layer consisting only of the base material). The protective layer may be a single layer or multiple layers.

[0028] As shown in Figures 2 and 3, the lead conductor 5 is a conductor that electrically connects the coil 3 and the external electrode 4. Lead conductor 5A electrically connects one end of the coil 3 (the end on the side 2c side of the coil conductor 6f) to the external electrode 4A that covers the end face 2a. Lead conductor 5B electrically connects the other end of the coil 3 (the end on the side 2c side of the coil conductor 6a) to the external electrode 4B that covers the end face 2b. Lead conductor 5 is made of a conductive material such as Ag or Pd. Lead conductor 5, like the coil conductor 6 and via 7, is patterned on each of the multiple layers 11 by printing or the like.

[0029] The lead conductor 5 has a plurality of end conductors 12 (12A, 12B) and a plurality of connecting conductors 13 (13A, 13B). In this embodiment, the lead conductor 5 constitutes a first path K1 formed by the end conductor 12A and the connecting conductor (first connecting conductor) 13A, and a second path K2 formed by the end conductor 12B and the connecting conductor (second connecting conductor) 13B. In the examples of Figures 2 and 3, in each of the lead conductors 5A and 5B, two first paths K1 are provided so as to sandwich one second path K2 in the X direction (stacking direction).

[0030] The lead conductors 5A and 5B are symmetrical with respect to the center line in the Y direction of the element 2 when viewed from the X direction. The first path K1 of lead conductor 5A extends from the end on the side 2c side of the coil conductors 6d and 6f of layers 11d and 11f toward the end face 2a and is exposed on the end face 2a (see Figure 4). In this embodiment, the positions of the two first paths K1 in the Z direction are equal to each other. As a result, when viewed from the X direction, the entirety of the two first paths K1 overlap each other.

[0031] The second path K2 of the lead conductor 5A extends from the side surface 2c end of the coil conductor 6e of layer 11e toward the end surface 2a and is exposed on the end surface 2a (see Figure 4). The exposed position of the second path K2 on the end surface 2a is shifted in the Z direction relative to the exposed position of the first path K1 on the end surface 2a. In this embodiment, the exposed position of the second path K2 on the end surface 2a is located on the side surface 2d side than the exposed position of the first path K1 on the end surface 2a.

[0032] The first path K1 of the lead conductor 5B extends from the end on the side 2c side of the coil conductors 6a and 6c of layers 11a and 11c toward the end face 2b, and is exposed on the end face 2b (see Figure 4). In this embodiment, the positions of the two first paths K1 in the Z direction are equal to each other. As a result, when viewed from the X direction, the entirety of the two first paths K1 overlap each other.

[0033] The second path K2 of the lead conductor 5B extends from the side surface 2c end of the coil conductor 6b of layer 11b toward the end surface 2a and is exposed on the end surface 2b (see Figure 4). The exposed position of the second path K2 on the end surface 2b is shifted in the Z direction relative to the exposed position of the first path K1 on the end surface 2b. In this embodiment, the exposed position of the second path K2 on the end surface 2b is located on the side surface 2d side than the exposed position of the first path K1 on the end surface 2b.

[0034] Figure 5 is a schematic enlarged view of the main components showing the detailed configuration of the lead conductor. Figure 5 shows the configuration of the lead conductor 5A connecting coil 3 and the first external electrode 4A, and the configuration of the lead conductor 5B connecting coil 3 and the second external electrode 4B is similar.

[0035] As described above, the end conductors 12A and 12B extend between the outer surface of the base body 2 (end face 2a in Figure 5) and the coil 3 at different positions in the X direction (stacking direction). When viewed from the X direction, the end conductors 12A and 12B extend in a straight line parallel to each other along the Y direction. The Y-direction extension lengths of the end conductors 12A and 12B are approximately the same. Furthermore, the Z-direction width W1 of the end conductor 12A when viewed from the X direction and the Z-direction width W2 of the end conductor 12A when viewed from the X direction are equal. In this embodiment, the Z-direction width W1 and W2 of the end conductor 12A are larger than the width W3 of the connecting conductor 13A, the width W4 of the connecting conductor 13B, and the width Wc of the coil 3 (width of coil conductors 6a to 6f).

[0036] The connecting conductors 13A and 13B are aligned in a straight line with the ends of the coil 3, respectively, and with the end conductors 12A and 12B. The width W3 of connecting conductor 13A and the width W4 of connecting conductor 13B are equal, for example, to the width Wc of the coil 3 (width of coil conductors 6a to 6f). In this embodiment, as described above, the coil 3 is circular when viewed from the X direction. Each of the connecting conductors 13A and 13B extends in the tangential direction of the circular coil 3. The contact point PA between the coil 3 and connecting conductor 13A is the point on the side 2c side of the coil 3. The contact point PB between the coil 3 and connecting conductor 13B is located on the end face 2a side and the side 2d side of contact point PA.

[0037] In the example shown in Figure 5, the end conductor 12A is positioned in the Z direction at a location corresponding to the contact PA. The connecting conductor 13A extends in a straight line along the Y direction from the contact PA toward the end face 2a and is connected to the end conductor 12A, which also extends in a straight line along the Y direction. As a result, the first path K1 formed by the end conductor 12A and the connecting conductor 13A is configured to lead the end of the coil 3 to the end face 2a without any bends.

[0038] Furthermore, in the example shown in Figure 5, the end conductor 12B is located on the side 2d side of the end conductor 12A in the Z direction. The amount of Z-direction displacement of the end conductor 12B relative to the end conductor 12A may be smaller than the Z-direction width W1 of the end conductor 12A, or it may be greater than or equal to the Z-direction width W1 of the end conductor 12A. In the former case, when viewed from the X direction, parts of the end conductors 12A and 12B overlap, while in the latter case, when viewed from the X direction, the end conductors 12A and 12B do not overlap. Figure 5 illustrates a configuration in which parts of the end conductors 12A and 12B do not overlap.

[0039] The end conductor 12B is positioned in the Z direction on the side 2d side rather than at the position corresponding to the contact PB. The connecting conductor 13B extends in a straight line from the contact PB toward the end face 2a, oblique to the connecting conductor 13A, and is connected to the end conductor 12B which extends in a straight line along the Y direction. The second path K2 formed by the end conductor 12B and the connecting conductor 13B has a bent portion at the connection point between the end conductor 12B and the connecting conductor 13B, but the connecting conductor 13B between the end conductor 12B and the coil 3 does not have a bent portion, and is configured to bring out the end of the coil 3 to the end face 2a.

[0040] In specifying the arrangement relationship between coil 3 and connecting conductor 13A and between coil 3 and connecting conductor 13B as described above, the widthwise centerline Lc of coil 3, the widthwise centerline La of connecting conductor 13A, and the widthwise centerline Lb of connecting conductor 13B can be used. That is, in the configuration of Figure 5, the widthwise centerline La of connecting conductor 13A is tangent to the widthwise centerline Lc of coil 3 at contact PA, and the widthwise centerline Lb of connecting conductor 13B is tangent to the widthwise centerline Lc of coil 3 at contact PB.

[0041] Figure 6 is a schematic enlarged view of the main part showing the connection between the end conductor and the connecting conductor. As described above, in this embodiment, the width W1 of the end conductor 12A in the Z direction and the width W2 of the end conductor 12B in the Z direction are larger than the width W3 of the connecting conductor 13A and the width W4 of the connecting conductor 13B. In addition, the connecting conductor 13B extends in a straight line diagonally to the connecting conductor 13A and is connected to the end conductor 12B which extends in a straight line along the Y direction.

[0042] In this embodiment, when connecting the end conductor 12B and the connecting conductor 13B, the length M1 of one end 12a in the width direction of the end conductor 12B that connects to the inner line F1 of the connecting conductor 13B and the length M2 of the other end 12b in the width direction of the end conductor 12B that connects to the outer line F2 of the connecting conductor 13B are different when viewed from the X direction (stacking direction).

[0043] In the example shown in Figure 6, the length M2 of the other end 12b of the end conductor 12B in the width direction is greater than the length M1 of the one end 12a of the end conductor 12B in the width direction. As a result, the connection point C2 between the outer line F2 of the connecting conductor 13B and the other end 12b of the end conductor 12B in the width direction is located on the coil 3 side in the Y direction relative to the connection point C1 between the inner line F1 of the connecting conductor 13B and the one end 12a of the end conductor 12B in the width direction.

[0044] As explained above, in the laminated coil component 1, the coil 3, which is located inside the base body 2, is led out to the outer surface of the base body 2 via multiple paths by the lead conductor 5. This reduces the DC resistance of the coil 3. In addition, in the laminated coil component 1, the connecting conductors 13A and 13B that connect the end conductors 12A and 12B to the ends of the coil 3 are in a straight line. In this way, the absence of bends in the connecting conductors 13A and 13B reduces eddy current losses in the lead conductor 5. As a result, the Q value is improved in this laminated coil component 1 by reducing the DC resistance of the coil 3 and reducing eddy current losses.

[0045] In this embodiment, when viewed from the X direction (stacking direction), the shape of the coil 3 is circular, and each of the connecting conductors 13A and 13B extends in the tangential direction of the coil 3. With this configuration, the circular coil 3 and the end conductors 12A and 12B can be connected over a short distance by the connecting conductors 13A and 13B. Therefore, eddy current losses when a circular coil 3 is used can be sufficiently reduced.

[0046] In this embodiment, when viewed from the X direction (stacking direction), the end conductors 12A and 12B are parallel to each other. Also, in this embodiment, when viewed from the X direction (stacking direction), the widths W1 and W2 of the end conductors 12A and 12B are equal to each other. With this configuration, for example, even if variations occur in the dimensions of the base body 2 (especially the dimensions in the Y direction) during the chipping process in the manufacturing of stacked coil components, variations between individual end conductors 12A and 12B in length and variations between individual end conductors 12A and 12B in spacing on the outer surface of the base body 2 can be suppressed. This makes it possible to suppress the increase in DC resistance due to excessive length of end conductors 12A and 12B, and the occurrence of cracks caused by the proximity of end conductors 12A and 12B to each other on the outer surface of the base body 2.

[0047] In this embodiment, when viewed from the X direction (stacking direction), the length M1 of one end of the end conductor 12B connected to the inner line F1 of the connecting conductor 13B and the length M2 of the other end of the end conductor 12B connected to the outer line F2 of the connecting conductor 13B are different. With this configuration, the width of the end conductor 12B, which is responsible for the electrical connection with the external electrode 4, can be kept constant, while the coil 3 and connecting conductor 13B, whose widths change according to the design value of the inductance, can be connected to the end conductor 12B at a gentle angle. This makes it possible to reduce the resistance between the external electrode 4 and the end conductor 12B, and to reduce the eddy current loss between the connecting conductor 13B and the end conductor 12B.

[0048] In the laminated coil component 1, the width Wc of the coil 3, the width W3 of the connecting conductor 13A, and the width W4 of the connecting conductor 13B are equal to each other. These widths Wc, W3, and W4 are parameters that affect the inductance value of the laminated coil component 1, and their design is modified according to the required inductance value of the laminated coil component 1. On the other hand, the widths W1 and W2 of the end conductors 12A and 12B are designed to have sufficient width from the viewpoint of reducing the connection resistance between the first path K1 and the second path K2 and the external electrode 4, and are not affected by the required inductance value of the laminated coil component 1. For this reason, in a normal design, the widths W1, W2 ≠ widths W3, W4, and in this embodiment as well, the widths W1, W2 > widths W3, W4.

[0049] Figure 7(a) shows the configuration when widths W1, W2 ≠ widths W3, W4, and the width W4 of the connecting conductor 13B is maintained, while the connection point C1' between the inner line F1 of the connecting conductor 13B and one end 12a in the width direction of the end conductor 12B, and the connection point C2' between the outer line F2 of the connecting conductor 13B and the other end 12b in the width direction of the end conductor 12B are aligned with the line of connection point C1 shown in Figure 6. In this case, the width W2' of the end conductor 12B is smaller than the width W2 of the end conductor 12B in the case of Figure 6.

[0050] Figure 7(b) shows the configuration when widths W1, W2 ≠ widths W3, W4, and the width W4 of the connecting conductor 13B is maintained, while the connection point C1' between the inner line F1 of the connecting conductor 13B and one end 12a in the width direction of the end conductor 12B, and the connection point C2' between the outer line F2 of the connecting conductor 13B and the other end 12b in the width direction of the end conductor 12B, are aligned with the line of connection point C2 shown in Figure 6. In this case as well, similar to Figure 7(a), the width W2' of the end conductor 12B is smaller than the width W2 of the end conductor 12B in the case of Figure 6.

[0051] Furthermore, Figure 8(a) shows the configuration when widths W1, W2 ≠ widths W3, W4, and the width W2 of the end conductor 12B is maintained, while the connection point C1' between the inner line F1 of the connecting conductor 13B and one end 12a in the width direction of the end conductor 12B, and the connection point C2' between the outer line F2 of the connecting conductor 13B and the other end 12b in the width direction of the end conductor 12B are aligned with the line of connection point C1 shown in Figure 6. In this case, the angle θ1' between the other end 12b in the width direction of the end conductor 12B and the outer line F2 of the connecting conductor 13B is smaller than the angle θ1 between the other end 12b in the width direction of the end conductor 12B and the outer line F2 of the connecting conductor 13B in the case of Figure 6.

[0052] Figure 8(b) shows the configuration when widths W1,W2≠W3,W4, and the width W2 of the end conductor 12B is maintained, while the connection point C1' between the inner line F1 of the connecting conductor 13B and one end 12a in the width direction of the end conductor 12B, and the connection point C2' between the outer line F2 of the connecting conductor 13B and the other end 12b in the width direction of the end conductor 12B, are aligned with the line of connection point C2 shown in Figure 6. In this case, the angle θ2' between one end 12a in the width direction of the end conductor 12B and the inner line F1 of the connecting conductor 13B is smaller than the angle θ2 between one end 12a in the width direction of the end conductor 12B and the inner line F1 of the connecting conductor 13B in the case of Figure 6.

[0053] As described above, by making the length M1 of one end of the connecting conductor 13B and the length M2 of the other end of the connecting conductor 13B different from each other, even when the width Wc of the coil 3 and the widths W3 and W4 of the connecting conductors 13A and 13B connected to the coil 3 are adjusted according to the desired inductance value, the width W2 of the end conductor 12B can be sufficiently secured. Therefore, the resistance between the external electrode 4 and the end conductor 12B is reduced. Furthermore, by keeping the angle θ1 between the other end 12b in the width direction of the end conductor 12B and the outer line F2 of the connecting conductor 13B, and the angle θ2 between the one end 12a in the width direction of the end conductor 12B and the inner line F1 of the connecting conductor 13B large, the eddy current loss between the connecting conductor 13B and the end conductor 12B is reduced.

[0054] Figure 9 is a schematic YZ cross-sectional view of a modified laminated coil component. As shown in Figure 9, the modified laminated coil component 21 differs from the laminated coil component 1 in the shape of the coil 3 when viewed from the X direction (lamination direction), and the shapes of the connecting conductors 13A and 13B have been adjusted accordingly.

[0055] Specifically, in the laminated coil component 21, the shape of the coil 3 when viewed from the X direction (lamination direction) is rectangular. The coil 3 is rectangular in shape and is arranged within the base body 2 such that its long side is along the Y direction and its short side is along the Z direction. The corner 3r of the coil 3 is an arc shape corresponding to a quarter circle. In the laminated coil component 21, as shown in Figure 10, the connecting conductor 13A extends in the direction of the extension of the straight side 3a of the coil 3. The connecting conductor 13B extends in the tangential direction of the corner 3r of the coil 3.

[0056] In the example shown in Figure 10, the end conductor 12A is positioned in the Z direction at a location corresponding to side 3a on the side 2c side of the coil 3. The connecting conductor 13A extends in a straight line in the Y direction from side 3a toward the end face 2a. The connecting conductor 13A is connected to the end conductor 12A, which also extends in a straight line along the Y direction. As a result, the first path K1 formed by the end conductor 12A and the connecting conductor 13A is configured to lead the end of the coil 3 to the end face 2a without any bending.

[0057] In the example shown in Figure 10, the end conductor 12B is positioned on the side 2d side in the Z direction, rather than on the side 2c side corresponding to side 3a. The connecting conductor 13B extends in a straight line from the contact PC, which corresponds to the top of the corner 3r, toward the end face 2a, at an angle to the connecting conductor 13A. The connecting conductor 13B is connected to the end conductor 12B, which extends in a straight line along the Y direction. The second path K2 formed by the end conductor 12B and the connecting conductor 13B has a bent portion at the connection point between the end conductor 12B and the connecting conductor 13B, but the connecting conductor 13B between the end conductor 12B and the coil 3 does not have a bent portion, and is configured to bring out the end of the coil 3 to the end face 2a.

[0058] In this laminated coil component 21, the same effects as those of the laminated coil component 1 described above are achieved, and the Q value is improved by reducing the DC resistance of the coil 3 and the eddy current loss. Furthermore, by adopting the configuration of connecting conductors 13A and 13B shown in Figure 10, the rectangular coil 3 and the end conductors 12A and 12B can be connected over a short distance by the connecting conductors 13A and 13B. Therefore, the eddy current loss when a rectangular coil 3 is used can be sufficiently reduced.

[0059] Figure 11 is a schematic YZ cross-sectional view of a laminated coil component according to another modification. As shown in Figure 11, the laminated coil component 31 according to another modification has a further difference in the shape of the coil 3 when viewed from the X direction (lamination direction) compared to the laminated coil components 1 and 21 described above, and the shapes of the connecting conductors 13A and 13B are adjusted accordingly.

[0060] Specifically, in the laminated coil component 31, the shape of the coil 3 when viewed from the X direction (lamination direction) is oval. Here, oval shape is defined by a pair of opposing straight sides 3b and a pair of arc-shaped sides 3c connecting the ends of the pair of sides 3b. The coil 3 is arranged within the base body 2 such that the pair of straight sides 3b are aligned along the Y direction. The arc-shaped sides 3c have a shape equivalent to a semicircle and face the end faces 2a and 2b. In the laminated coil component 31, as shown in Figure 12, the connecting conductor 13A extends in the direction of the extension of the straight side 3b of the coil 3. The connecting conductor 13B extends in the tangential direction of the arc-shaped side 3c of the coil 3.

[0061] In the example shown in Figure 12, the end conductor 12A is positioned in the Z direction at a location corresponding to side 3b on the side 2c side of the coil 3. The connecting conductor 13A extends in a straight line in the Y direction from side 3b toward the end face 2a. The connecting conductor 13A is connected to the end conductor 12A, which also extends in a straight line along the Y direction. As a result, the first path K1 formed by the end conductor 12A and the connecting conductor 13A is configured to lead the end of the coil 3 to the end face 2a without any bending.

[0062] In the example shown in Figure 12, the end conductor 12B is positioned in the Z direction closer to side 2d than to the position corresponding to side 3b on side 2c. The connecting conductor 13B extends toward end face 2a from a contact point PD located slightly closer to end face 2a than the end of the straight side 3b on the arc-shaped side 3c. The connecting conductor 13B extends in a straight line oblique to the connecting conductor 13A and is connected to the end conductor 12B, which extends in a straight line along the Y direction. The second path K2 formed by the end conductor 12B and the connecting conductor 13B has a bent portion at the connection point between the end conductor 12B and the connecting conductor 13B, but the connecting conductor 13B between the end conductor 12B and the coil 3 does not have a bent portion, and is configured to bring out the end of the coil 3 toward end face 2a.

[0063] In this laminated coil component 31, the same effects as those of the laminated coil components 1 and 21 described above are achieved, improving the Q value by reducing the DC resistance of the coil 3 and the eddy current loss. Furthermore, by adopting the configuration of connecting conductors 13A and 13B shown in Figure 12, the rectangular coil 3 and the end conductors 12A and 12B can be connected over a short distance by the connecting conductors 13A and 13B. Therefore, the eddy current loss when using a rectangular coil 3 can be sufficiently reduced. [Explanation of Symbols]

[0064] 1, 21, 31…Laminated coil component, 2…Base body, 3…Coil, 3a, 3b…Straight edge, 3c…Arch-shaped edge, 3r…Corner, 4…External electrode (4A, 4B), 11…Layer, 5(5A, 5B)…Lead-out conductor, 12(12A, 12B)…End conductor, 13(13A, 13B)…Connecting conductor, W1, W2…Width of end conductor, M1…Length of one end of connecting conductor in the width direction, M2…Length of the other end of connecting conductor in the width direction.

Claims

1. A base body formed by stacking multiple layers in a predetermined stacking direction, A coil arranged inside the aforementioned body, External electrodes arranged on the outer surface of the aforementioned body, The coil and the external electrode are electrically connected by a lead conductor, The aforementioned lead conductor is A plurality of end conductors extending between the outer surface of the base body and the coil at different positions in the stacking direction, A laminated coil component having a plurality of connecting conductors that connect each of the plurality of end conductors and the end of the coil in a straight line.

2. When viewed from the aforementioned stacking direction, The shape of the aforementioned coil is circular. The laminated coil component according to claim 1, wherein each of the plurality of connecting conductors extends in the tangential direction of the coil.

3. When viewed from the aforementioned stacking direction, The shape of the coil is rectangular with arc-shaped corners. The laminated coil component according to claim 1, wherein the plurality of connecting conductors are composed of a first connecting conductor extending in the direction of the extension of the straight side of the coil and a second connecting conductor extending in the tangential direction of the corner of the coil.

4. When viewed from the aforementioned stacking direction, The shape of the coil is an oval shape having a pair of opposing straight sides and a pair of arc-shaped sides connecting the ends of the pair of sides. The laminated coil component according to claim 1, wherein the plurality of connecting conductors are composed of a first connecting conductor extending in the direction of the extension of the linear side of the coil and a second connecting conductor extending in the tangential direction of the arc-shaped side of the coil.

5. The laminated coil component according to any one of claims 1 to 4, wherein, when viewed from the lamination direction, the plurality of end conductors are parallel to each other.

6. The laminated coil component according to any one of claims 1 to 4, wherein, when viewed from the aforementioned lamination direction, the widths of the plurality of end conductors are equal to each other.

7. The laminated coil component according to any one of claims 1 to 4, wherein, when viewed from the lamination direction, the length of one end of the end conductor in the width direction connected to the inner line of the connecting conductor and the length of the other end of the end conductor in the width direction connected to the outer line of the connecting conductor are different from each other.

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