Coil component

Abstract

To enable a suppression of an increase of an AC resistance caused by a phase difference of an AC current.SOLUTION: A coil component includes: a pair of resist layers 11 and 12; a coil 20 that includes a coil main body 21 formed in a spiral shape to between the resist layers 11 and 12; and an insulation layer 30. The coil main body 21 includes a division layer 22 that is divided into them in a thickness direction of each of the first resist layers 11. The coil 20 includes a connection part 23 connected to one end and the other end of an extension direction of the plurality of division layers 22 while being extended to the thickness direction. The insulation layer 30 insulates both of the division layers 22 so as to be provide to between the plurality of division layers 22. A cross sectional area of the plurality of division layers 22 is different each other so that a phase difference of an AC current flowing in the plurality of division layers 22 becomes smaller as compared with the case where the cross sectional area of the plurality of division layers 22 is the same each other.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a coil component.

Background Art

[0002] Patent Document 1 describes a coil printed wiring board (hereinafter referred to as a coil component) that constitutes a power receiving module of a non-contact power supply system. In the coil component described in Patent Document 1, a spiral first coil portion formed on one surface of an insulating layer and a spiral second coil portion formed on the other surface of the insulating layer are electrically connected in parallel. That is, the spiral coil body is configured to be divided into a first divided layer and a second divided layer via an insulating layer. Therefore, compared with the case where the coil body is not divided into a plurality of divided layers via the insulating layer, the cross-sectional area through which the alternating current flows becomes smaller. The smaller the cross-sectional area through which the alternating current flows, the smaller the influence of the skin effect that occurs when the alternating current flows. Therefore, according to the coil component described in Patent Document 1, the alternating current resistance can be reduced by suppressing the skin effect.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in a configuration in which the coil body is divided into a plurality of divided layers via an insulating layer like the coil component described in Patent Document 1, the distance from the connection portion connected to both ends of the coil body to the divided layer, that is, the length of the current path, is different for each divided layer. For this reason, a difference occurs in the phase of the alternating current flowing through the divided layers between the divided layers. Depending on the difference in the phase of the alternating current, the alternating current resistance increases. From this, there is room for improvement in suppressing an increase in the alternating current resistance.

Means for Solving the Problem

[0005] The coil component for solving the above problem has a pair of resist layers, a coil having a coil body formed in a spiral shape between the resist layers, and an insulating layer. The coil body has divided layers divided into a plurality in the thickness direction of the resist layer. The coil has a connection portion that extends in the thickness direction and is connected to one end and the other end in the extending direction of the plurality of divided layers, respectively. The insulating layer is provided between the plurality of divided layers to insulate the divided layers from each other, and the cross-sectional areas of the plurality of divided layers are different from each other such that the phase difference of the alternating current flowing through the plurality of divided layers is smaller than when the cross-sectional areas of the plurality of divided layers are the same as each other.

Brief Description of the Drawings

[0006]

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Embodiment for Carrying out the Invention

[0007] Hereinafter, with reference to FIGS. 1 to 9, an embodiment in which a coil component is embodied as a power receiving coil of a non-contact power supply system will be described. As shown in FIGS. 1 to 4, the coil component has a pair of resist layers 11 and 12, a coil 20, and an insulating layer 30.

[0008] <First resist layer 11> As shown in FIGS. 1 to 4, the first resist layer 11 is formed of a well-known resin material having insulation properties such as an epoxy resin or a polyimide resin.

[0009] <Second resist layer 12> As shown in FIGS. 1, 3, and 4, the second resist layer 12 is formed of the same material as the first resist layer 11. A pair of connection holes 13 are formed in the second resist layer 12 at positions corresponding to a pair of connection portions 23 of the coil 20 described later. At the upper ends of the connection portions 23, conducting wires (not shown in the figures) are connected through the connection holes 13.

[0010] <Coil 20> As shown in FIGS. 1, 3, and 4, the coil 20 has a coil body 21 formed in a spiral shape between the resist layers 11 and 12, and a pair of connection portions 23 connected to one end and the other end in the extending direction of the coil body 21, respectively.

[0011] The coil body 21 has divided layers 22 that are divided into a plurality of parts in the thickness direction of the first resist layer 11. Hereinafter, the thickness direction of the first resist layer 11 will simply be referred to as the thickness direction. In this embodiment, the coil body 21 is divided into six divided layers 22 in the thickness direction. The divided layers 22 are formed of copper foil.

[0012] One of the pair of connection parts 23 extends in the thickness direction and is connected to one end in the extending direction of the plurality of divided layers 22. The other of the pair of connection parts 23 extends in the thickness direction and is connected to the other end in the extending direction of the plurality of divided layers 22. The connection part 23 is formed of copper.

[0013] <Insulating layer 30> As shown in FIGS. 3 and 4, the insulating layer 30 is provided between the plurality of divided layers 22 to insulate the divided layers 22 from each other. The insulating layer 30 is formed of, for example, an epoxy resin containing glass fibers.

[0014] Note that the first resist layer 11 and the second resist layer 12 are formed by coating one side and the other side (the lower surface and the upper surface in FIG. 4) of the integrated coil 20 and insulating layer 30, respectively.

[0015] The cross-sectional areas of the plurality of divided layers 22 are different from each other such that the phase difference of the alternating current flowing through the plurality of divided layers 22 becomes smaller than when the cross-sectional areas of the plurality of divided layers 22 are the same as each other. In the present embodiment, the thicknesses of the cross-sections of the plurality of divided layers 22 are the same as each other, and the widths of the cross-sections of the plurality of divided layers 22 are different from each other. Note that an alternating current of 79 kHz or more and 90 kHz or less flows through the coil component of the present embodiment.

[0016] Next, the detailed configurations of the coil components of the comparative example and the first to fourth embodiments will be described. (Comparative example) In the comparative example, the widths of the cross-sections of the plurality of divided layers 22 are all 5.0 mm. The thicknesses of the cross-sections of the plurality of divided layers 22 are all 0.1 mm.

[0017] As shown in FIG. 5, in the comparative example, the ratio of the phase difference of the alternating current flowing through the plurality of divided layers 22 was 22.1%. Here, the ratio of the phase difference is set to 100% when the difference between the largest and the smallest of the phases of the alternating current flowing through the plurality of divided layers 22 is 180 degrees.

[0018] (First embodiment) In the first embodiment, the widths of the cross-sections of the dividing layers 22 are 1.4 mm, 2.6 mm, 3.8 mm, 6.2 mm, 7.4 mm, and 8.6 mm in order from the uppermost side in the thickness direction, that is, the side closest to the second resist layer 12. The thicknesses of the cross-sections of the plurality of dividing layers 22 are all 0.1 mm.

[0019] As shown in FIG. 6, in the first embodiment, the ratio of the phase difference of the alternating current flowing through the plurality of dividing layers 22 was 3.3%. (Second Embodiment) In the second embodiment, the widths of the cross-sections of the dividing layers 22 are 8.6 mm, 7.4 mm, 6.2 mm, 3.8 mm, 2.6 mm, and 1.4 mm in order from the uppermost side in the thickness direction, that is, the side closest to the second resist layer 12. The thicknesses of the cross-sections of the plurality of dividing layers 22 are all 0.1 mm.

[0020] As shown in FIG. 7, in the second embodiment, the ratio of the phase difference of the alternating current flowing through the plurality of dividing layers 22 was 10.8%. (Third Embodiment) In the third embodiment, the widths of the cross-sections of the dividing layers 22 are 3.8 mm, 4.2 mm, 4.6 mm, 5.4 mm, 5.8 mm, and 6.2 mm in order from the uppermost side in the thickness direction, that is, the side closest to the second resist layer 12. The thicknesses of the cross-sections of the plurality of dividing layers 22 are all 0.1 mm.

[0021] As shown in FIG. 8, in the third embodiment, the ratio of the phase difference of the alternating current flowing through the plurality of dividing layers 22 was 19.2%. (Fourth Embodiment) In the fourth embodiment, the widths of the cross-sections of the dividing layers 22 are 5.6 mm, 5.4 mm, 5.2 mm, 4.8 mm, 4.6 mm, and 4.4 mm in order from the uppermost side in the thickness direction, that is, the side closest to the second resist layer 12. The thicknesses of the cross-sections of the plurality of dividing layers 22 are all 0.1 mm.

[0022] As shown in FIG. 9, in the fourth embodiment, the ratio of the phase difference of the alternating current flowing through the plurality of dividing layers 22 was 21.2%. In the first to fourth embodiments, the phase difference of the alternating current flowing through the plurality of divided layers 22 is smaller than that of the coil body 21 of the comparative example.

[0023] <Operation of this Embodiment> In the coil component of this embodiment, a capacitor is formed by two divided layers 22 sandwiching an insulating layer 30. In this embodiment, by making the cross-sectional areas of the divided layers 22 different from each other, the capacitance of the capacitor becomes different from the capacitance of the capacitor of the comparative example. Since the capacitance of the capacitor is different, the phase of the alternating current changes. Therefore, by making the cross-sectional areas of the divided layers 22 different from each other, the phase of the alternating current flowing through each divided layer 22 can be changed. And according to the first to fourth embodiments of this embodiment, the phase difference of the alternating current flowing through the plurality of divided layers 22 becomes smaller than when the cross-sectional areas of the plurality of divided layers 22 are the same as each other.

[0024] <Effect of this Embodiment> Next, the effects of this embodiment will be described. (1) The cross-sectional areas of the plurality of divided layers 22 are different from each other such that the phase difference of the alternating current flowing through the plurality of divided layers 22 is smaller than when the cross-sectional areas of the plurality of divided layers 22 are the same as each other.

[0025] According to such a configuration, since the above-described operation is exhibited, an increase in the AC resistance caused by the phase difference of the alternating current can be suppressed. (2) The thicknesses of the cross-sections of the plurality of divided layers 22 are the same as each other, and the widths of the cross-sections of the plurality of divided layers 22 are different from each other.

[0026] According to such a configuration, the cross-sectional area of the divided layer 22 can be made different without changing the thickness of the divided layer 22, that is, without changing the distance between the insulating layers 30. <Modification Example> This embodiment can be implemented by making the following changes. This embodiment and the following modification examples can be implemented in combination with each other within a technically non-conflicting range.

[0027] ·In the above-described embodiment, the frequency of the alternating current flowing through the coil component is not limited to 79 kHz or more and 90 kHz or less, and may be lower than 79 kHz or higher than 90 kHz.

[0028] ·The number of the divided layers 22 is not limited to six. The number of the divided layers 22 can be appropriately changed as long as it is two or more. ·In the above-described embodiment, an example of the configuration in which the thicknesses of the cross-sections of the plurality of divided layers 22 are the same as each other and the widths of the cross-sections of the plurality of divided layers 22 are different from each other is illustrated, but the present invention is not limited thereto. As shown in FIG. 10, the widths of the cross-sections of the plurality of divided layers 22 may be the same as each other and the thicknesses of the cross-sections of the plurality of divided layers 22 may be different from each other. According to such a configuration, it is possible to make the cross-sectional areas of the divided layers 22 different from each other while making the widths of the cross-sections of the divided layers 22 the same as each other.

[0029] ·By making both the widths and the thicknesses of the cross-sections of the plurality of divided layers 22 different from each other, the cross-sectional areas of the divided layers 22 may be made different from each other.

Explanation of Reference Numerals

[0030] 11…First resist layer 12…Second resist layer 13…Connection hole 20…Coil 21…Coil body 22…Divided layer 23…Connection part 30…Insulating layer

Claims

1. A pair of resist layers, a coil having a coil body formed in a spiral shape between the resist layers, and an insulating layer, wherein the coil body has divided layers divided into a plurality in the thickness direction of the resist layer, the coil has a connection portion that extends in the thickness direction and is connected to one end and the other end in the extending direction of the plurality of divided layers, respectively, the insulating layer is provided between the plurality of divided layers to insulate the divided layers from each other, the cross-sectional areas of the plurality of divided layers are different from each other such that the phase difference of the alternating current flowing through the plurality of divided layers is smaller than when the cross-sectional areas of the plurality of divided layers are the same as each other, a coil component.

2. The thicknesses of the cross-sections of the plurality of divided layers are the same as each other, and the widths of the cross-sections of the plurality of divided layers are different from each other, The coil component according to Claim 1.

3. The widths of the cross-sections of the plurality of divided layers are the same as each other, and the thicknesses of the cross-sections of the plurality of divided layers are different from each other, The coil component according to Claim 1.

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