JP2018198237A - Coil component - Google Patents

Abstract

To reduce a height of a coil component in a coil axis direction, the coil component including a coil conductor that is configured by folding a metal plate multiple times.SOLUTION: A coil component comprises a coil conductor 100 consisting of a metal plate that is wound over multiple winding layers L1-L5 and including a first holding part A1, a step part B and a second folding part A2 in a winding direction. The metal plate is shifted from the winding layer L1 to the winding layer L2 by being folded in the first folding part A1, shifted from the winding layer L2 to the winding layer L1 by being folded in the step part B, and shifted from the winding layer L1 to the winding layer L2 by being folded in the second folding part A2. Thus, the metal plate is returned from the winding layer L2 to the winding layer L1 by using the step part B, such that a large clearance is prevented from being generated between the winding layers. Therefore, a height in a coil axis direction can be reduced further than the prior arts.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a coil component, and more particularly to a coil component including a coil conductor formed by bending a metal plate a plurality of times.

  Although coil parts are used for various applications, among them, since a large current flows through a coil part for a power supply, the DC resistance is reduced by using a coil conductor having a large cross-sectional area. As a method of using a coil conductor having a large cross-sectional area, a method of forming a coil conductor wound across a plurality of winding layers by preparing a meander-shaped metal plate and folding it back a plurality of times is considered. It is done.

  FIG. 14 is a schematic perspective view showing an example of a coil conductor 100X produced by bending a meander-like metal plate a plurality of times.

  The coil conductor 100X shown in FIG. 14 has a turn number of 4.5 turns by folding the meander-shaped metal plate 8 times. However, every time the metal plate is folded, the position of the metal plate transitions to the next winding layer. Therefore, when the metal plate is folded eight times as in the coil conductor shown in FIG. 14, nine winding layers L1 to L9 are formed. There is a problem that the height in the coil axis direction becomes large. This is because the number of turns per turn is two, and therefore, two wound layers are occupied per turn.

  In order to solve such a problem, as described in Patent Document 1, there is a method in which the number of turns per turn is set to one by devising the shape of the metal plate before turning. .

JP 2013-187454 A

  However, although the method described in Patent Document 1 is effective when the number of turns is small, the shape of the metal plate before being folded back is greatly restricted. Therefore, when the number of turns is large, especially the turn exceeding 4 turns. It is difficult to get a number. In addition, the method described in Patent Document 1 has a problem in that the folded-back portion of the metal plate protrudes in various directions, so that the planar size as viewed from the coil axis direction increases.

  Therefore, the present invention provides a structure capable of reducing the height in the coil axis direction without limiting the number of turns in a coil component including a coil conductor formed by bending a metal plate a plurality of times. Objective.

  A coil component according to the present invention includes a coil conductor made of a metal plate wound over a plurality of winding layers, and having a first folded portion, a stepped portion, and a second folded portion along the winding direction. The plurality of winding layers include at least a first winding layer and a second winding layer, and the metal plate is folded back at the first folding portion so that the second winding layer is separated from the first winding layer. Transition to the first winding layer by being bent at the stepped portion, transitioning from the second winding layer to the first winding layer, and folding at the second folded portion, thereby A transition from one winding layer to the second winding layer is characterized.

  According to the present invention, the metal plate transitioned from the first winding layer to the second winding layer by the first folded portion is used to convert the metal plate from the second winding layer to the first winding layer using the step portion. Therefore, a large gap does not occur between the winding layers. For this reason, it becomes possible to make the height in a coil axial direction lower than before.

  In the present invention, the metal plate forms a plurality of turns, and each of the plurality of turns includes first, second, and third conductor portions, and the first folded portion includes the first conductor portion and the first conductor portion. The metal plate is folded between the second conductor portions, and the step portion is a portion where the metal plate is folded between the second conductor portion and the third conductor portion. The portion may be a portion where the metal plate is folded between the third conductor portion and the first conductor portion of the next turn along the winding direction. In this manner, a plurality of turns can be formed by repeating a pattern including the first folded portion, the stepped portion, and the second folded portion a plurality of times.

  In the present invention, the plurality of winding layers further include a third winding layer adjacent to the second winding layer, and the plurality of turns includes first and second turns adjacent to each other, The first, second, and third conductor portions included in the first turn are positioned in the first, second, and first winding layers, respectively, and the first, second, and third included in the second turn. The conductor portions may be located in the second, third and second winding layers, respectively. Thus, if one winding layer is shared by a plurality of turns, the metal plate can be wound at high density without generating a useless gap.

  In the present invention, when viewed from the coil axis direction, the first conductor portions included in each of the plurality of turns overlap each other, and the second conductor portions included in each of the plurality of turns overlap each other. The third conductor portions included in each may overlap each other. According to this, the planar size viewed from the coil axis direction can be reduced.

  In the present invention, as viewed from the coil axis direction, the first folded portions included in each of the plurality of turns do not overlap each other, and the stepped portions included in each of the plurality of turns do not overlap each other, The second folded portions included therein may be configured so as not to overlap each other. According to this, the interference of the 1st and 2nd folding | turning part and level | step-difference part between adjacent turns can be avoided.

  In the present invention, the conductor width of the metal plate in the first and second folded portions may be narrower than the conductor width of the metal plate in the first, second, and third conductor portions. According to this, since the occupation width of the first and second folded portions is reduced, it is possible to form more turns.

  In the present invention, the conductor width of the metal plate in the stepped portion may be the same as the conductor width of the metal plate in the second and third conductor portions. According to this, it becomes possible to prevent an increase in DC resistance at the stepped portion.

  In the present invention, when viewed from the coil axis direction, the coil conductor includes first and second extending regions extending in the first direction, and a second direction extending in the second direction orthogonal to the first direction. 3 and 4, the first folded portion is formed in the first extending region, the second folded portion is formed in the second extending region, and the stepped portion is the third extending portion. It may be formed in the extended region. According to this, the shape of the metal plate before folding can be simplified.

  The coil component according to the present invention may further include an insulating layer provided between metal plates located in adjacent winding layers. According to this, it is possible to prevent short-circuit defects in adjacent winding layers.

  The coil component according to the present invention may further include a magnetic member that covers the coil conductor. According to this, higher inductance can be obtained.

  Thus, according to the present invention, it is possible to reduce the height in the coil axial direction in a coil component including a coil conductor formed by bending a plurality of metal plates. In addition, since the number of turns is not limited, a larger inductance can be obtained.

FIG. 1 is a schematic perspective view for explaining a configuration of a coil conductor 100 which is a main part of a coil component according to an embodiment of the present invention. FIG. 2 is a schematic exploded perspective view of the coil component 201 including the coil conductor 100. 3A is a schematic perspective view of the coil component 201, and FIG. 3B is a schematic perspective view showing a cut model of the coil component 201. FIG. 4A is a schematic perspective view of the coil component 202 including the coil conductor 100, and FIG. 4B is a schematic perspective view showing a cut model of the coil component 202. FIG. 5 is a schematic perspective view of the coil component 203 including the coil conductor 100. FIG. 6 is a schematic perspective view of the coil component 204 including the coil conductor 100. FIG. 7 is a schematic perspective view of the coil component 205 including the coil conductor 100. FIG. 8 is a diagram for explaining a manufacturing process of the coil conductor 100. FIG. 9 is a diagram for explaining a manufacturing process of the coil conductor 100. FIG. 10 is a diagram for explaining a manufacturing process of the coil conductor 100. FIG. 11 is a diagram for explaining a manufacturing process of the coil conductor 100. FIG. 12 is a diagram for explaining a manufacturing process of the coil conductor 100. FIG. 13 is a diagram for explaining a manufacturing process of the coil conductor 100. FIG. 14 is a schematic perspective view of a conventional coil conductor 100X.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a schematic perspective view for explaining a configuration of a coil conductor 100 which is a main part of a coil component according to an embodiment of the present invention.

  The coil conductor 100 shown in FIG. 1 has a configuration wound 4.5 turns by folding a metal plate a plurality of times. The coil conductor 100 has five winding layers L1 to L5 stacked in the z direction, which is the coil axis direction, and each winding layer includes first and second metal plates extending in the y direction. The extending regions R1 and R2 and the third and fourth extending regions R3 and R4 in which the metal plate extends in the x direction are provided. In the example shown in FIG. 1, the first and second extending regions R1 and R2 form a short side, and the third and fourth extending regions R3 and R4 form a long side. However, it is not limited to this. Further, it is not necessary that the outer shape of the coil conductor 100 viewed from the coil axis direction is rectangular. The metal plate is made of a good conductor such as copper (Cu), and the surface thereof may be covered with an insulating layer. When the surface is not covered with an insulating layer, the metal plate is insulated between adjacent metal plates in the z direction. It is preferable to arrange the layers.

  The winding layers L1 to L5 are arranged in this order when viewed from the coil axis direction. Of these, the conductor portions 111 and 113 are located in the winding layer L1, the conductor portions 121, 112, and 123 are located in the winding layer L2, and the conductor portions 131, 122, and 133 are located in the winding layer L3. The conductor portions 141, 132, and 143 are located in the winding layer L4, and the conductor portions 151 and 142 are located in the winding layer L5. The conductor portions 111 to 113 constitute a first turn, the conductor portions 121 to 123 constitute a second turn, the conductor portions 131 to 133 constitute a third turn, and the conductor portions 141 to 143 constitute a fourth turn. The conductor portion 151 constitutes the remaining 0.5 turn. The conductor portions 111, 121, 131, 141, 151 overlap each other when viewed from the z direction, and the conductor portions 112, 122, 132, 142 overlap each other when viewed from the z direction, and the conductor portions 113, 123, 133, 143 overlap each other when viewed from the z direction.

  Between the conductor portions 111, 121, 131, and 141 and the conductor portions 112, 122, 132, and 142, first folded portions A1 are provided, respectively. The first folded portion A1 is located in the first extending region R1. The first folded portion A1 is a part that transitions the position of the metal plate from the upper winding layer to the lower winding layer by folding the metal plate about 180 °. For example, the conductor portions 111 and 112 are located in the winding layers L1 and L2, respectively, and the transition of the winding layer between them is realized by the first folded portion A1.

  Step portions B are provided between the conductor portions 112, 122, 132, 142 and the conductor portions 113, 123, 133, 143, respectively. The step portion B is located in the third extending region R3. The stepped portion B is a portion that transitions the position of the metal plate from the lower winding layer to the upper winding layer by bending the metal plate into a crank shape. For example, the conductor portions 112 and 113 are located in the winding layers L2 and L1, respectively, and the transition of the winding layer between them is realized by the step portion B.

  Between the conductor portions 113, 123, 133, and 143 and the conductor portions 121, 131, 141, and 151, second folded portions A2 are provided, respectively. The second folded portion A2 is located in the second extending region R2. The second folded portion A2 is a portion that changes the position of the metal plate from the upper winding layer to the lower winding layer by folding the metal plate about 180 °. For example, the conductor portions 113 and 121 are located in the winding layers L1 and L2, respectively, and the transition of the winding layer between them is realized by the second folded portion A2.

  With such a configuration, when the end E1 of the coil conductor 100 is a starting point, the first turn made up of the conductor portions 111 to 113 is such that the conductor portion 111 is positioned in the winding layer L1 and the conductor portion is formed by the first turn-up portion A1. 112 transitions to the winding layer L2, and the stepped portion B causes the conductor portion 113 to transition to the winding layer L1. Next, in the second turn composed of the conductor parts 121 to 123, the conductor part 121 transitions to the winding layer L2 by the second folded part A2, and the conductor part 122 becomes the wound layer L3 by the first folded part A1. The conductor part 123 changes to the winding layer L2 by the step part B. And the conductor part 131 changes to the winding layer L3 by 2nd folding | turning part A2. Thereafter, the metal plate is wound in the same manner.

  Thus, in the present embodiment, the metal plate is folded back multiple times, and the stepped portion B is provided between the first folded portion A1 and the second folded portion A2. The first and second turn-up portions A1 and A2 each appear once per turn, and when considering the end direction E1 of the coil conductor 100 as a starting point along the winding direction, both are upper layer windings. The transition is made from a layer to a lower winding layer. For this reason, in the coil conductor shown in FIG. 14 in which the stepped portion B is not provided, two winding layers are occupied per turn, and nine winding layers L1 to L9 are formed when 4.5 turns are wound. Necessary. On the other hand, in the present embodiment, a stepped portion B is provided between the first folded portion A1 and the second folded portion A2, whereby the position of the metal plate is changed from the lower winding layer to the upper winding layer. Part of the same winding layer is shared by the two turns. For this reason, in the case of winding 4.5 turns, the number of winding layers required is five, and it is possible to realize a significantly lower profile than in the past.

  In order to realize such a winding pattern, the position of the first folded portion A1 included in each turn, the position of the stepped portion B included in each turn, the second folded portion A2 included in each turn Each position needs to be shifted from the z direction. Specifically, considering the end portion E1 of the coil conductor 100 as the starting point along the winding direction, the first and second folded portions A1 and A2 are shifted in the y direction so that the positions of the first and second folded portions A1 and A2 are closer to each other in the lower turn. The lower turn is shifted in the x direction so that the position of the stepped portion B is behind. Thereby, interference of the metal plate between adjacent turns is prevented.

  In the example shown in FIG. 1, the metal plate is turned 4.5 times, but the number of turns is not limited to this, and a larger number of turns can be formed. The number of turns is limited by the first and second folded portions A1, A2 or the stepped portion B, and is wound for any number of turns within a range in which the interference between the first and second folded portions A1, A2 or the stepped portion B does not occur. Is possible.

  In the present embodiment, the conductor width of the metal plate in the first and second folded portions A1 and A2 is designed to be narrower than the conductor width in other portions. This is for facilitating the folding of the metal plate in the portion, and for forming more turns by reducing the occupied width in the y direction of the first and second folded portions A1, A2. It is. On the other hand, the conductor width of the metal plate in the stepped portion B is the same as the conductor width of the metal plate in the front and rear portions, for example, the second conductor portion 112 and the third conductor portion 113. This is because even if the conductor width of the stepped portion B is narrowed, the occupied width in the x direction of the stepped portion B does not change, and the conductor width of the metal plate in the stepped portion B is the same as the conductor width of the front and rear portions. Thus, an increase in direct current resistance in the stepped portion B is prevented.

  FIG. 2 is a schematic exploded perspective view of the coil component 201 including the coil conductor 100. 3A is a schematic perspective view of the coil component 201, and FIG. 3B is a schematic perspective view showing a cut model of the coil component 201.

  A coil component 201 shown in FIGS. 2 and 3 includes ferrite cores 211 and 212 that cover the coil conductor 100. The ferrite core 211 has a shape in which the central portion protrudes in the z direction, and the ferrite core 212 has a shape in which the central portion is recessed in the z direction. The coil conductor is formed in an annular space formed by combining them. 100 is accommodated. One end E1 and the other end E2 of the coil conductor 100 are exposed to the outside through a notch provided in the ferrite core 212. If such ferrite cores 211 and 212 are provided, higher inductance can be obtained.

  FIG. 4A is a schematic perspective view of the coil component 202 including the coil conductor 100, and FIG. 4B is a schematic perspective view showing a cut model of the coil component 202.

  A coil component 202 shown in FIG. 4 includes a composite magnetic body 213 that covers the coil conductor 100. The composite magnetic body 213 is a material in which a magnetic powder made of ferrite, a metal magnetic body, or the like and a resin are mixed. One end E1 and the other end E2 of the coil conductor 100 are exposed to the outside of the composite magnetic body 213. By using such a composite magnetic body 213, it is possible to increase the inductance without separately manufacturing a ferrite core.

  5 to 7 are schematic perspective views of coil components 203 to 205 including the coil conductor 100, respectively. Each of the coil components 203 to 205 has a configuration in which the coil conductor 100 is accommodated in the magnetic member 214. The magnetic member 214 may be a ferrite core or a composite magnetic body.

  The coil component 203 shown in FIG. 5 is exposed to the outside by extending one end E1 and the other end E2 of the coil conductor 100 downward (z direction) and bending the tip end in the x direction. . As described above, when the end portions E1 and E2 of the coil conductor 100 are extended to the mounting surface (xy surface) of the coil component 203, the coil component 203 can be surface-mounted on the printed board.

  The coil component 204 shown in FIG. 6 includes L-shaped external terminals E10 and E20 that cover the mounting surface (xy surface) and the side surface (yz surface) of the magnetic member 214. The external terminal E10 is connected to one end E1 of the coil conductor 100, and the external terminal E20 is connected to the other end E2 of the coil conductor 100. Providing such external terminals E10 and E20 increases the connection area with the land pattern formed on the printed circuit board, so that the mounting strength and connection reliability can be increased.

  The coil component 205 shown in FIG. 7 includes U-shaped external terminals E10 and E20 that cover the mounting surface (xy surface), side surface (yz surface), and upper surface (xy surface) of the magnetic member 214. The external terminal E10 is connected to one end E1 of the coil conductor 100, and the external terminal E20 is connected to the other end E2 of the coil conductor 100. Providing such external terminals E10 and E20 eliminates the directivity of the coil component 205 in the z direction, which makes it easier to mount on the printed circuit board.

  Next, a method for manufacturing the coil conductor 100 will be described with reference to FIGS.

  First, as shown in FIG. 8, a metal plate 100A is prepared with the x direction as the longitudinal direction and the z direction as the thickness direction. The metal plate 100A may be made of a good conductor such as copper (Cu), and an insulating layer may be provided on the surface thereof. Next, as shown in FIG. 9, the meander-shaped metal plate 100B is produced by punching the metal plate 100A. 9A is a plan view, and FIG. 9B is a perspective view. The same applies to FIGS. 10, 12 and 13.

  As shown in FIG. 9, the metal plate 100B is a meander-shaped flat plate made of conductor portions 111 to 113, 121 to 123, 131 to 133, 141 to 143, 151, and one end thereof constitutes an end E1, The other end constitutes an end E2. Further, the conductor width of the metal plate 100B is partially narrowed, and this portion is a portion that becomes the first and second folded portions A1 and A2. As shown in FIG. 9, there are four first folded portions A1, and their positions in the y direction are different from each other. Similarly, there are four second folded portions A2, and their positions in the y direction are different from each other.

  Next, as shown in FIG. 10, a metal plate 100C having a stepped portion B is produced by bending a part of the metal plate 100B into a crank shape. Thus, the conductor portions 112, 113, 122, 123, 132, 133, 142, and 143 are defined with the stepped portion B as a boundary. 11 is an enlarged view for explaining the shape of the stepped portion B in more detail, and shows a region C shown in FIG. 10B, that is, a boundary portion between the conductor portion 112 and the conductor portion 113. As shown in FIG. 11, the step formed by the stepped portion B is set to an amount slightly larger than the thickness of the metal plate 100C. Four stepped portions B are formed, and their positions in the x direction are gradually shifted in the straight portion of the metal plate 100B.

  Next, as shown in FIG. 12, a loop composed of the conductor portions 142, 143, and 151 is formed by folding back the second folded portion A2 positioned between the conductor portion 143 and the conductor portion 151 by 180 °. Thereby, a part of winding layer L5 and winding layer L4 is completed. Furthermore, as shown in FIG. 13, the winding layer L4 is completed by folding back the first folded portion A1 positioned between the conductor portion 141 and the conductor portion 142 by 180 °. Thereafter, similarly, when the second folded portion A2 and the first folded portion A1 are alternately folded, the coil conductor 100 shown in FIG. 1 is completed.

  As described above, the coil conductor 100 according to the present embodiment can be easily obtained by punching a metal plate, bending to form the stepped portion B, and folding back the first and second folded portions A1 and A2. Can be produced.

  In addition, since the coil conductor 100 according to the present embodiment has two turns per turn, a simple metal plate 100A having a longitudinal direction in the x direction can be used, and a stamped metal plate can be used. Also about 100B, it is not a complicated shape like patent document 1, but can be made into the simple meander shape extended in ax direction.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention. Needless to say, it is included in the range.

100, 100X Coil conductors 100A-100C Metal plates 111, 121, 131, 141, 151 First conductor portions 112, 122, 132, 142 Second conductor portions 113, 123, 133, 143 Third conductor portions 201- 205 Coil parts 211, 212 Ferrite core 213 Composite magnetic body 214 Magnetic member A1 First folded portion A2 Second folded portion B Stepped portion C Regions E1, E2 End portions E10, E20 of coil conductors External terminals L1-L9 Winding Layer R1 First extension region R2 Second extension region R3 Third extension region R4 Fourth extension region

Claims (10)

A coil conductor comprising a metal plate wound over a plurality of winding layers, and having a first folded portion, a stepped portion and a second folded portion along the winding direction,
The plurality of winding layers include at least first and second winding layers,
When the metal plate is folded at the first folded portion, the metal plate transitions from the first wound layer to the second wound layer, and is folded at the stepped portion, so that the second winding is performed. A coil which changes from the first winding layer to the second winding layer by transitioning from the winding layer to the first winding layer and being folded back at the second folded portion. parts. The metal plate forms a plurality of turns,
Each of the plurality of turns includes first, second and third conductor portions,
The first folded portion is a portion where the metal plate is folded between the first conductor portion and the second conductor portion,
The step portion is a portion where the metal plate is bent between the second conductor portion and the third conductor portion,
The second folded portion is a portion where the metal plate is folded between the third conductor portion and the first conductor portion of the next turn along the winding direction. Item 2. The coil component according to Item 1. The plurality of winding layers further include a third winding layer adjacent to the second winding layer,
The plurality of turns includes first and second turns adjacent to each other,
The first, second, and third conductor portions included in the first turn are located in the first, second, and first winding layers, respectively.
The first, second, and third conductor portions included in the second turn are located in the second, third, and second winding layers, respectively. Coil parts.   When viewed from the coil axis direction, the first conductor portions included in the plurality of turns overlap each other, the second conductor portions included in the plurality of turns overlap each other, and the plurality of turns 4. The coil component according to claim 2, wherein the third conductor portions included in each turn overlap each other. 5.   When viewed from the coil axis direction, the first folded portions included in the plurality of turns do not overlap each other, the stepped portions included in the plurality of turns do not overlap each other, and the plurality of turns The coil component according to claim 4, wherein the second folded portions included in the turns do not overlap each other.   The conductor width of the metal plate in the first and second folded portions is narrower than the conductor width of the metal plate in the first, second, and third conductor portions. Coil parts.   The coil component according to claim 6, wherein a conductor width of the metal plate in the step portion is the same as a conductor width of the metal plate in the second and third conductor portions. The coil conductor includes first and second extending regions extending in a first direction and third and third extending in a second direction orthogonal to the first direction when viewed from the coil axis direction. Having a fourth extension region;
The first folded portion is formed in the first extending region, the second folded portion is formed in the second extending region, and the stepped portion is formed in the third extending region. The coil component according to any one of claims 1 to 7, wherein the coil component is provided.   The coil component according to claim 1, further comprising an insulating layer provided between the metal plates positioned in adjacent winding layers.   The coil component according to any one of claims 1 to 9, further comprising a magnetic member that covers the coil conductor.

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