阅读说明：本技术 线圈构造体及其制造方法、引线框、以及电感器 (Coil structure, method for manufacturing same, lead frame, and inductor ) 是由 林真太郎 于 2021-04-28 设计创作，主要内容包括：本发明提供一种能够容易地增加卷绕数的构造的线圈构造体。其为n片金属板层叠而成的线圈构造体,n为2以上的自然数,各个上述金属板包括螺旋状的导线部、以及在上述导线部的外侧使形成为比上述导线部厚的n+1个以上的厚板部在规定方向排列而成的端子列,各个上述金属板的上述导线部的两端与各个上述金属板的相邻的任两个上述厚板部连结,各个上述金属板层叠,并且相邻的上述金属板的上述端子列彼此接合,最下层的上述导线部的两端与上述端子列的一端侧的两个上述厚板部连结,每上升一层,与上述导线部的两端连结的上述厚板部的位置分别向上述端子列的另一端侧移动一个位置,从而各个上述金属板的上述导线部串联连接而形成螺旋状的线圈。(The invention provides a coil structure with a structure capable of easily increasing the winding number. The coil structure is formed by stacking n metal plates, wherein n is a natural number of 2 or more, each metal plate comprises a spiral lead portion and a terminal array formed by arranging thick plate portions of n +1 or more, which are thicker than the lead portion, in a predetermined direction outside the lead portion, both ends of the lead portion of each metal plate are connected with any two adjacent thick plate portions of each metal plate, and each metal plate is stacked, and the terminal rows of the adjacent metal plates are joined to each other, both ends of the lead portion of the lowermost layer are connected to the two thick plate portions on one end side of the terminal rows, and each of the two thick plate portions is raised one layer, the positions of the thick plate portions connected to both ends of the lead portion are shifted by one position toward the other end side of the terminal row, so that the lead portions of the metal plates are connected in series to form a spiral coil.)

1. A coil structure in which n metal plates are laminated, n being a natural number of 2 or more,

each of the metal plates includes a helical lead portion and a terminal row formed by arranging thick plate portions, which are formed to be thicker than the lead portion by n +1 or more, in a predetermined direction outside the lead portion,

both ends of the lead portion of each of the metal plates are connected to any two of the adjacent thick plate portions of each of the metal plates,

each of the metal plates is laminated, and the terminal rows of the adjacent metal plates are joined to each other,

both ends of the wire portion of the lowermost layer are connected to the two thick plate portions on one end side of the terminal row, and the positions of the thick plate portions connected to both ends of the wire portion are shifted one by one toward the other end side of the terminal row every time the wire portion is raised one by one, so that the wire portions of the metal plates are connected in series to form a spiral coil.

2. The coil construct of claim 1 wherein,

the thick plate portion laminated at one end of the terminal row and the thick plate portion laminated at the other end of the terminal row serve as external connection terminals.

3. The coil construct according to claim 1 or 2, wherein,

in the terminal row of each of the metal plates, the thick plate portions other than the thick plate portions connected to both ends of the lead portion are electrically independent from the lead portion and serve as support portions for supporting the thick plate portions of the terminal row of the other metal plate.

4. The coil construct according to any one of claims 1 to 3, wherein,

an insulating film covering the surface of each of the metal plates.

5. The coil construct according to any one of claims 1 to 4, wherein,

the coil structure includes:

a plurality of product regions which become inductors when singulated; and

a frame portion for supporting each of the product areas from the peripheral side,

the lead portions and the terminal rows are formed in the respective product areas.

6. The coil construct of claim 5 wherein,

the frame portion includes:

a first portion having the same thickness as the lead portion; and

and a second portion having the same thickness as the thick plate portion constituting the terminal row.

7. An inductor, having:

the coil construct of any one of claims 1 to 6; and

and a sealing resin covering the coil structure so that a part of the terminal row is exposed.

8. The inductor of claim 7,

the sealing resin contains a filler of a magnetic substance.

9. A lead frame comprises a spiral lead portion and a terminal array formed by arranging more than 3 thick plate portions which are formed thicker than the lead portion and have the same thickness in a specified direction outside a spiral formed by the lead portion,

both ends of the lead portion are connected to any two of the thick plate portions constituting the terminal row.

10. A method for manufacturing a coil structure in which n metal plates are laminated, n being a natural number of 2 or more,

the method for manufacturing the coil structure comprises the following steps:

a step of patterning a plate-shaped metal to form n pieces of the metal plate, wherein the metal plate comprises a spiral lead portion and a terminal array formed by arranging thick plate portions which are formed to be thicker than n +1 of the lead portion in a specified direction outside the lead portion; and

laminating the metal plates and joining the terminal rows of the adjacent metal plates to each other,

in the step of forming the metal plates, both ends of the lead portion of each of the metal plates are connected to any two of the thick plate portions adjacent to each other of the metal plates,

in the joining step, the metal plates are laminated such that the two ends of the wire portion at the lowermost layer are connected to the two thick plate portions at one end side of the terminal row, and the positions of the thick plate portions connected to the two ends of the wire portion are shifted by one position toward the other end side of the terminal row for each step, whereby the wire portions of the metal plates are connected in series to form a spiral coil.

Technical Field

The invention relates to a coil structure, a method of manufacturing the same, a lead frame, and an inductor.

Background

In some circuits, an inductor is used for the purpose of stabilizing a current, converting a voltage, or the like. In recent years, electronic devices such as game machines and smartphones have been increasingly downsized, and along with this, downsizing of inductors mounted on such electronic devices is also required, and surface-mount inductors have been proposed.

An example of an inductor to be mounted on such an electronic device is a structure in which a coil structure having a wound coil formed of a thin metal plate is sealed with a resin.

< Prior Art document >

< patent document >

Patent document 1: japanese unexamined patent publication No. 2020-027820

Disclosure of Invention

< problems to be solved by the present invention >

However, in a coil structure having a winding coil formed of a thin metal plate, it is necessary to increase the number of windings in order to obtain a large induced electromotive force, but it is difficult to increase the number of windings in a conventional structure.

The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a coil structure having a structure in which the number of windings can be easily increased.

< means for solving the problems >

The coil structure is a coil structure formed by stacking n (n is a natural number of 2 or more) metal plates, each metal plate includes a spiral lead portion and a terminal array formed by arranging thick plate portions formed to be thicker than the lead portion by n +1 or more in a predetermined direction outside the lead portion, both ends of the lead portion of each metal plate are connected to any two adjacent thick plate portions of each metal plate, and each metal plate is stacked, and the terminal rows of the adjacent metal plates are joined to each other, both ends of the lead portion of the lowermost layer are connected to the two thick plate portions on one end side of the terminal rows, and each of the two thick plate portions is raised one layer, the positions of the thick plate portions connected to both ends of the lead portion are shifted by one position toward the other end side of the terminal row, so that the lead portions of the metal plates are connected in series to form a spiral coil.

< effects of the invention >

According to the disclosed technology, a coil structure having a structure in which the number of windings can be easily increased can be provided.

Drawings

Fig. 1 is a plan view illustrating a coil structure according to a first embodiment.

Fig. 2 is a perspective view of one product region of fig. 1 (a).

Fig. 3 is a plan view (1) illustrating the vicinity of the product region of each metal plate before lamination.

Fig. 4 is a plan view (2) illustrating the vicinity of the product region of each metal plate before lamination.

Fig. 5 is a plan view (3) illustrating the vicinity of the product region of each metal plate before lamination.

Fig. 6 is a cross-sectional view taken along line a-a to line G-G of the first metal plate 10.

Fig. 7 is a cross-sectional view of the coil structure 1 taken along the line a-a and the line B-B in fig. 3 (a).

Fig. 8 is a cross-sectional view of the coil structure 1 taken along the lines C-C and D-D in fig. 3 (a).

Fig. 9 is a cross-sectional view of the coil structure 1 taken along the lines E-E and F-F in fig. 3 (a).

Fig. 10 is a cross-sectional view of the coil structure 1 taken along the line G-G in fig. 3 (a).

Fig. 11 is a view (1) illustrating a manufacturing process of the coil structure according to the first embodiment.

Fig. 12 is a view (2) illustrating a manufacturing process of the coil structure according to the first embodiment.

Fig. 13 is a diagram illustrating a manufacturing process of the inductor according to the first embodiment.

Fig. 14 is a perspective view showing an inductor of the first embodiment by way of example.

Fig. 15 is a sectional view for explaining a method of mounting the inductor according to the first embodiment.

Fig. 16 is a sectional view illustrating a coil structure according to modification 1 of the first embodiment.

Fig. 17 is a sectional view showing an inductor according to modification 1 of the first embodiment by way of example.

Fig. 18 is a view illustrating a manufacturing process of the coil structure according to modification 1 of the first embodiment.

Fig. 19 is a perspective view showing an example of an inductor according to modification 1 of the first embodiment.

Fig. 20 is a sectional view for explaining a method of mounting an inductor according to modification 1 of the first embodiment.

Description of reference numerals:

1. 3 coil structure

1A, 1B external connection terminal

2. 4 inductor

10 first metal plate

11. 21, 31, 41, 51, 61 wire guide part

12. 22, 32, 42, 52, 62 terminal columns

13. 23, 33, 43, 53, 63 connection part

14. 24, 34, 44, 54, 64 reinforcements

20 second metal plate

30 third metal plate

40 fourth metal plate

50 th metal plate

60 sixth metal plate

70. 71 sealing resin

80 insulating film

111. 211, 311, 411, 511, 611 starting point

112. 212, 312, 412, 512, 612 end points

121. 621 terminal part

122、222₁、222₂、322₁、322₂、422₁、422₂、522₁、522₂、622 connecting part

123₁To 123₅、223₁To 223₅、323₁To 323₅、423₁To 423₅、523₁To 523₅、623₁To 623₅Support part

Detailed Description

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and a description thereof may be omitted.

< first embodiment >

Fig. 1 is a plan view illustrating a coil structure according to a first embodiment, where fig. 1 (a) is an overall view, and fig. 1 (b) is an enlarged view of the vicinity of one product region M in fig. 1 (a). Fig. 2 is a perspective view of one product region of fig. 1 (a).

Referring to fig. 1 (a), 1 (b), and 2, the coil structure 1 has a structure in which a plurality of metal plates are stacked and metal plates adjacent to each other in the vertical direction are joined to each other. The plurality of metal plates may have a two-layer structure in this case, and in the present embodiment, the coil structure 1 having a 6-layer structure in which the first metal plate 10, the second metal plate 20, the third metal plate 30, the fourth metal plate 40, the fifth metal plate 50, and the sixth metal plate 60 are sequentially stacked is illustrated.

The coil structure 1 has a plurality of product regions M arranged in a vertical and horizontal direction in a plan view. Each product region M is a region in which the entire coil structure 1 is sealed with resin and then singulated into inductors. Frame portions N in a frame shape for supporting each product region M from the peripheral side are formed around each product region M, and adjacent frame portions N are formed integrally with each other and are connected to each other. In fig. 1 (a), as an example, 18 product regions M are arranged (3 rows and 6 columns), but the present invention is not limited thereto.

Fig. 3 to 5 are plan views illustrating the vicinity of the product region of each metal plate before lamination. Specifically, (a) of fig. 3 is a plan view of the first metal plate 10. Fig. 3 (b) is a plan view of the second metal plate 20. Fig. 4 (a) is a plan view of the third metal plate 30. Fig. 4 (b) is a plan view of the fourth metal plate 40. Fig. 5 (a) is a plan view of the fifth metal plate 50. Fig. 5 (b) is a plan view of the sixth metal plate 60.

The first metal plate 10, the second metal plate 20, the third metal plate 30, the fourth metal plate 40, the fifth metal plate 50, and the sixth metal plate 60 each have the same plan view shape as that of fig. 1 (a), and fig. 3 (a) to 5 (b) are views showing portions of the respective metal plates (the vicinity of one product area) corresponding to fig. 1 (b), by way of example. In fig. 3 (a) to 5 (b), the gray portion shows the thin plate portion, and the pear skin pattern portion shows the thick plate portion which is formed thicker than the thin plate portion and protrudes downward from the thin plate portion. The thin plate part is formed integrally with the thick plate part.

In fig. 3 to 5, of the product regions M, the product region of the first metal plate 10 is set to M1, the product region of the second metal plate 20 is set to M2, the product region of the third metal plate 30 is set to M3, the product region of the fourth metal plate 40 is set to M4, the product region of the fifth metal plate 50 is set to M5, and the product region of the sixth metal plate 60 is set to M6. In fig. 3 to 5, of the frame portions N, the frame portion of the first metal plate 10 is N1, the frame portion of the second metal plate 20 is N2, the frame portion of the third metal plate 30 is N3, the frame portion of the fourth metal plate 40 is N4, the frame portion of the fifth metal plate 50 is N5, and the frame portion of the sixth metal plate 60 is N6.

Fig. 6 is a cross-sectional view of the first metal plate 10 taken along line a-a to line G-G in fig. 3 (a). Specifically, (a) of fig. 6 is a cross-sectional view of the first metal plate 10 taken along the line a-a of fig. 3 (a). Fig. 6 (B) is a cross-sectional view of the first metal plate 10 taken along line B-B of fig. 3 (a). Fig. 6 (C) is a cross-sectional view of the first metal plate 10 taken along the line C-C in fig. 3 (a). Fig. 6 (D) is a cross-sectional view of the first metal plate 10 taken along the line D-D in fig. 3 (a). Fig. 6 (E) is a cross-sectional view of the first metal plate 10 taken along line E-E of fig. 3 (a). Fig. 6 (F) is a cross-sectional view of the first metal plate 10 taken along the line F-F in fig. 3 (a). Fig. 6 (G) is a cross-sectional view of the first metal plate 10 taken along line G-G of fig. 3 (a). In fig. 6, for convenience, a portion of the terminal row connected to the lead portion is shown with hatching different from that of other portions (the same may be true for the following drawings).

As shown in fig. 3 (a) and 6, the product area M1 of the first metal plate 10 includes a lead portion 11 formed in a substantially rectangular spiral shape, and a terminal row 12 arranged in a predetermined direction outside the spiral formed by the lead portion 11. The lead portion 11 is connected to the frame portion N1 by a plurality of connection portions 13 (6 in this example) extending from the inside of the product region M1 to the outside of the product region M1. The number and connection positions of the connection portions 13 may be determined arbitrarily as long as the lead portion 11 can be stably supported by the frame portion N1, and are preferably arranged in the vicinity of the corners of the substantially rectangular lead portion 11.

The terminal row 12 includes a terminal portion 121, a coupling portion 122, and a supporting portion 123 arranged at predetermined intervals in this order from the left side of fig. 3 (a)₁To 123₅. The lead portion 11, the connection portion 13, and the frame portion N1 are thin plate portions formed to have a predetermined thickness, and the terminal portion 121, the connection portion 122, and the support portion 123₁To 123₅Is a thick plate portion formed to have the same thickness as the thickness of the lead portion 11. Terminal 121, coupling portion 122, and support portion 123₁To 123₅The shape of (2) in plan view is, for example, square or rectangular.

The upper surfaces (surfaces on the second metal plate 20 side) of the lead portions 11, the connection portions 13, and the frame portion N1, the terminal portions 121, the connection portions 122, and the support portions 123₁To 123₅Are located on substantially the same plane. On the other hand, the lower surfaces of the lead portions 11, the connecting portions 13, and the frame portion N1 are positioned relative to the terminal portion 121, the connecting portion 122, and the supporting portion 123₁To 123₅The lower surface of (b) is a position recessed toward the second metal plate 20 side. Here, when the inductor is manufactured from the coil structure 1 and mounted on a substrate, a surface opposite to the substrate is set as a lower surface, and a surface opposite to the lower surface is set as an upper surface (the same applies hereinafter).

The frame portion N1 may include a first portion having the same thickness as the wire portion 11 and a second portion having the same thickness as the thick plate portion constituting the terminal row 12. For example, as the second portion, in order to reinforce the frame portion N1 and prevent the inclination of the metal plate, reinforcing portions 14 may be provided at four corners of the frame portion N1. In this case, the lower surface of the reinforcing portion 14 is located on substantially the same plane as the lower surface of the terminal portion 121 and the like. The reinforcing portion 14 may be formed in an L-shape, for example. In order to prevent the inclination of the metal plate while reinforcing the frame portion N1, a second portion (thick plate portion) may be provided in a portion other than the corner portion of the frame portion N1 instead of the reinforcing portion 14 or in addition to the reinforcing portion 14.

Terminal 121, coupling portion 122, and support portion 123₁To 123₅The thickness of (2) is, for example, about 50 to 500 μm, and the thickness of the lead portion 11, the connection portion 13, and the frame portion N1 is, for example, about half of that of the terminal portion 121. When reinforcing portion 14 is provided in frame portion N1, reinforcing portion 14 has the same thickness as terminal portion 121 and the like.

The terminal portion 121 is disposed inside the product region M1, and one side thereof extends to the outside of the product region M1 and is connected to the frame portion N1. The portion extending from the terminal portion 121 is a thin plate portion like the connecting portion 13. The other side of the terminal portion 121 is connected to the starting point 111 of the lead portion 11. The connecting portion 122 is disposed inside the product region M1, and one side thereof extends outside the product region M1 and is connected to the frame portion N1. The portion extending from the coupling portion 122 is a thin plate portion similar to the coupling portion 13. The other side of the connecting portion 122 is connected to the end point 112 of the lead portion 11.

Support 123₁To 123₅Is disposed inside the product region M1, and one side thereof extends to the outside of the product region M1 and is connected to the frame portion N1. Self-supporting part 123₁To 123₅The extended portion is a thin plate portion identical to the connecting portion 13. Support 123₁To 123₅The other side of the lead wire portion 11 is not connected. That is, the support portion 123₁To 123₅And is not electrically conducted to the lead portion 11. In this way, in the terminal row 12 of the first metal plate 10, the thick plate portions other than the thick plate portions (the terminal portion 121 and the coupling portion 122) coupled to both ends of the lead portion 11 are electrically independent from the lead portion 11 and serve as terminal rows for supporting other metal platesA support portion for the thick plate portion.

As shown in fig. 3 (b), the second metal plate 20 differs from the first metal plate 10 in that the connection portions between the start and end points of the lead portions and the terminal rows are shifted by one position to the right with respect to the first metal plate 10, and has the same overall shape and thickness as the first metal plate 10.

Specifically, the product area M2 of the second metal plate 20 includes the lead portion 21 formed in a substantially rectangular spiral shape, and the terminal row 22 arranged in a predetermined direction outside the spiral formed by the lead portion 21. The lead portion 21 is connected to the frame portion N2 by a plurality of connection portions 23 (6 in this example) extending from the inside of the product region M2 to the outside of the product region M2. The number and connection positions of the connection portions 23 may be arbitrarily determined as long as the lead portions 21 can be stably supported by the frame portion N2, and are preferably arranged in the vicinity of the corners of the substantially rectangular lead portions 21.

The terminal row 22 has support portions 223 arranged at predetermined intervals in order from the left side of fig. 3 (b)₁And a connecting part 222₁And a connecting part 222₂And a support part 223₂To 223₅. The lead portion 21, the connection portion 23, and the frame portion N2 are thin plate portions formed to have a predetermined thickness, and the connection portion 222₁And a connecting part 222₂And a support part 223₁To 223₅Is a thick plate portion formed to have the same thickness as the thickness of the lead portion 21. Connecting part 222₁And a connecting part 222₂And a support part 223₁To 223₅For example, the shape of the connection portion 122, the terminal portion 121, and the support portion 123 in plan view₁To 123₅Have the same shape in plan view.

The lead portion 21, the connection portion 23, and the upper surface (the surface on the third metal plate 30 side) of the frame portion N2 and the connection portion 222₁And a connecting part 222₂And a support part 223₁To 223₅Are located on substantially the same plane. On the other hand, the lower surfaces of the lead portion 21, the connection portion 23, and the frame portion N2 are positioned opposite to the connection portion 222₁And a connecting part 222₂And a support part 223₁To 223₅The lower surface of (b) is a position recessed toward the third metal plate 30 side.

The frame portion N2 may include a first portion having the same thickness as the wire portion 21 and a second portion having the same thickness as the thick plate portion constituting the terminal row 22. For example, as the second portion, in order to prevent the metal plates from inclining while securing the joint with the adjacent metal plates, the reinforcing portions 24 may be provided at the four corners of the frame portion N2. In this case, the lower surface of the reinforcing portion 24 is positioned at the connection portion 222₁Etc. are substantially coplanar. The reinforcement portion 24 may be formed in an L-shape, for example. In order to prevent the metal plates from inclining while making the joint with the adjacent metal plates firm, a second portion (thick plate portion) may be provided in a portion other than the corner portion of the frame portion N2 instead of the reinforcing portion 24, or in addition to the reinforcing portion 24.

The thickness of the lead portion 21, the connection portion 23, and the frame portion N2 is the same as that of the lead portion 11, for example, and the connection portion 222₁And a connecting part 222₂And a support part 223₁To 223₅For example, the thickness of (2) is the same as that of the terminal portion 121.

Connecting part 222₁And 222₂Is disposed inside the product region M2, and one side thereof extends to the outside of the product region M2 and is connected to the frame portion N2. Self-coupling feature 222₁And 222₂The extended portion is a thin plate portion identical to the connecting portion 23. Connecting part 222₁The other side of the lead portion 21 is connected to the starting point 211 of the lead portion 21. Connecting part 222₂The other side thereof is connected to the end point 212 of the lead portion 21.

Support 223₁To 223₅Is disposed inside the product region M2, and one side thereof extends to the outside of the product region M2 and is connected to the frame portion N2. Self-supporting portion 223₁To 223₅The extended portion is a thin plate portion identical to the connecting portion 23. Support 223₁To 223₅The other side of the lead wire portion 21 is not connected. That is, the support portion 223₁To 223₅And is not electrically conducted to the lead portion 21. In this way, in the terminal row 22 of the second metal plate 20, the thick plate portions (the connection portions 222) connected to both ends of the lead portions 21₁And 222₂) The other thick plate portions are electrically independent from the lead portions 21, and serve as support portions for the thick plate portions supporting the terminal rows of the other metal plates.

As shown in fig. 4 (a), the third metal plate 30 differs from the second metal plate 20 in that the connection portions between the start and end points of the lead portions and the terminal rows are shifted by one position to the right, and has the same overall shape and thickness as the second metal plate 20.

Specifically, the product area M3 of the third metal plate 30 includes the lead portion 31 formed in a substantially rectangular spiral shape, and the terminal row 32 arranged in a predetermined direction outside the spiral formed by the lead portion 31. The lead portion 31 is connected to the frame portion N3 by a plurality of connection portions 33 (6 in this example) extending from the inside of the product region M3 to the outside of the product region M3. The number and connection positions of the connection portions 33 may be arbitrarily determined as long as the lead portion 31 can be stably supported by the frame portion N3, and are preferably arranged in the vicinity of the corner portions of the substantially rectangular lead portion 31.

The terminal row 32 has supporting portions 323 arranged at predetermined intervals in order from the left side of fig. 4 (a)₁And 323₂And a connecting part 322₁And a connecting part 322₂And a support part 323₃To 323₅. The lead part 31, the connection part 33, and the frame part N3 are thin plate parts formed with a predetermined thickness, and the connection part 322₁And a connecting part 322₂And a support part 323₁To 323₅Is a thick plate portion formed to have the same thickness as the thickness of the lead portion 31. Connecting part 322₁And a connecting part 322₂And a support part 323₁To 323₅For example, the shape of the connection portion 122, the terminal portion 121, and the support portion 123 in plan view₁To 123₅Have the same shape in plan view.

The lead portion 31, the connection portion 33, and the upper surface (the surface on the fourth metal plate 40 side) of the frame portion N3 and the connection portion 322₁And a connecting part 322₂And a support part 323₁To 323₅Are located on substantially the same plane. On the other hand, the lead portion 31, the connection portion 33, and the lower portion of the frame portion N3The surface is located opposite to the connecting part 322₁And a connecting part 322₂And a support part 323₁To 323₅The lower surface of (b) is a position recessed toward the fourth metal plate 40 side.

The frame portion N3 may include a first portion having the same thickness as the wire portion 31 and a second portion having the same thickness as the thick plate portion constituting the terminal row 32. For example, as the second portion, in order to prevent the metal plates from inclining while securing the joint with the adjacent metal plates, the reinforcing portions 34 may be provided at the four corners of the frame portion N3. In this case, the lower surface of the reinforcing portion 34 is positioned at the connection portion 322₁Etc. are substantially coplanar. The reinforcement portion 34 is formed in an L-shape, for example. In order to prevent the metal plates from inclining while making the joint with the adjacent metal plates firm, a second portion (thick plate portion) may be provided in a portion other than the corner portion of the frame portion N3 instead of the reinforcing portion 34 or in addition to the reinforcing portion 34.

The thickness of the lead portion 31, the connection portion 33, and the frame portion N3 is the same as that of the lead portion 11, for example, and the connection portion 322₁And a connecting part 322₂And a support part 323₁To 323₅For example, the thickness of (2) is the same as that of the terminal portion 121.

Connecting part 322₁And 322₂Is disposed inside the product region M3, and one side thereof extends to the outside of the product region M3 and is connected to the frame portion N3. Self-coupling portion 322₁And 322₂The extended portion is a thin plate portion identical to the connecting portion 33. Connecting part 322₁The other side of the lead portion 31 is connected to the starting point 311 of the lead portion 31. Connecting part 322₂The other side of which is connected to the end point 312 of the lead portion 31.

Support portion 323₁To 323₅Is disposed inside the product region M3, and one side thereof extends to the outside of the product region M3 and is connected to the frame portion N3. Self-supporting portion 323₁To 323₅The extended portion is a thin plate portion identical to the connecting portion 33. Support portion 323₁To 323₅The other side of the lead wire portion 31 is not connected. That is, the support portion 323₁To 323₅And is not electrically conducted to the lead portion 31. Thus, in the third metal plate 30In the terminal row 32, thick plate portions (connecting portions 322) connected to both ends of the lead portions 31₁And 322₂) The other thick plate portions are electrically independent from the lead portions 31, and serve as support portions for the thick plate portions supporting the terminal rows of the other metal plates.

As shown in fig. 4 (b), the fourth metal plate 40 differs from the third metal plate 30 in that the connection portions between the start and end points of the lead portions and the terminal rows are shifted by one position to the right with respect to the third metal plate 30, and has the same overall shape and thickness as the third metal plate 30.

Specifically, the product area M4 of the fourth metal plate 40 includes the lead portion 41 formed in a substantially rectangular spiral shape, and the terminal row 42 arranged in a predetermined direction outside the spiral formed by the lead portion 41. The lead wire portion 41 is connected to the frame portion N4 by a plurality of connection portions 43 (6 in this example) extending from the inside of the product region M4 to the outside of the product region M4. The number and connection positions of the connection portions 43 may be determined arbitrarily as long as the lead portions 41 can be stably supported by the frame portion N4, and are preferably arranged in the vicinity of the corners of the substantially rectangular lead portions 41.

The terminal row 42 has support portions 423 arranged at predetermined intervals in order from the left side of fig. 4 (b)₁To 423₃And a connecting part 422₁And a connecting part 422₂And a support part 423₄And 423₅. The lead portion 41, the connection portion 43, and the frame portion N4 are thin plate portions formed to have a predetermined thickness, and the connection portion 422₁And a connecting part 422₂And a support part 423₁To 423₅Is a thick plate portion formed to have the same thickness as the thickness of the lead portion 41. Coupling portion 422₁And a connecting part 422₂And a support part 423₁To 423₅For example, the shape of the connection portion 122, the terminal portion 121, and the support portion 123 in plan view₁To 123₅Have the same shape in plan view.

The lead portion 41, the connection portion 43, and the upper surface (the surface on the fifth metal plate 50 side) of the frame portion N4 and the connection portion 422₁And a connecting part 422₂And a support part 423₁To 423₅Upper surface (fifth metal plate 50 side)The faces) lie in substantially the same plane. On the other hand, the lower surfaces of the lead portion 41, the connection portion 43, and the frame portion N4 are positioned opposite to the connection portion 422₁And a connecting part 422₂And a support part 423₁To 423₅The lower surface of (b) is a position recessed toward the fifth metal plate 50 side.

The frame portion N4 may include a first portion having the same thickness as the lead portion 41 and a second portion having the same thickness as the thick plate portion constituting the terminal row 42. For example, as the second portion, in order to prevent the metal plates from inclining while securing the joint with the adjacent metal plates, reinforcing portions 44 may be provided at four corners of the frame portion N4. In this case, the lower surface of the reinforcing portion 44 is positioned at the connection portion 422₁Etc. are substantially coplanar. The reinforcing portion 44 is formed in an L shape, for example. In order to prevent the metal plates from inclining while making the joint with the adjacent metal plates firm, a second portion (thick plate portion) may be provided in a portion other than the corner portion of the frame portion N4 instead of the reinforcing portion 44 or in addition to the reinforcing portion 44.

The thickness of the lead portion 41, the connection portion 43, and the frame portion N4 is the same as that of the lead portion 11, for example, and the connection portion 422₁And a connecting part 422₂And a support part 423₁To 423₅For example, the thickness of the terminal portion 121.

Coupling portion 422₁And 422₂Is disposed inside the product region M4, and one side thereof extends to the outside of the product region M4 and is connected to the frame portion N4. Self-coupling portion 422₁And 422₂The extended portion is a thin plate portion identical to the connecting portion 43. Coupling portion 422₁The other side of the lead portion 41 is connected to the starting point 411 of the lead portion 41. Coupling portion 422₂The other side of the lead portion 41 is connected to the end point 412 of the lead portion 41.

Support 423₁To 423₅Is disposed inside the product region M4, and one side thereof extends to the outside of the product region M4 and is connected to the frame portion N4. Self-supporting portion 423₁To 423₅The extended portion is a thin plate portion identical to the connecting portion 43. Support 423₁To 423₅The other side of the lead wire portion 41 is not connected. That is, the support part423₁To 423₅And is not electrically conducted to the lead portion 41. In this way, in the terminal row 42 of the fourth metal plate 40, the thick plate portions (the connection portions 422) connected to both ends of the lead portions 41 are formed₁And 422₂) The other thick plate portions are electrically independent from the lead portions 41, and serve as support portions for the thick plate portions supporting the terminal rows of the other metal plates.

As shown in fig. 5 (a), the fifth metal plate 50 differs from the fourth metal plate 40 in that the connection portions between the start and end points of the lead portions and the terminal rows are shifted by one position to the right, and has the same overall shape and thickness as the fourth metal plate 40.

Specifically, the product area M5 of the fifth metal plate 50 includes the lead portion 51 formed in a substantially rectangular spiral shape, and the terminal row 52 arranged in a predetermined direction outside the spiral formed by the lead portion 51. The lead portion 51 is connected to the frame portion N5 by a plurality of connection portions 53 (6 in this example) extending from the inside of the product region M5 to the outside of the product region M5. The number and connection positions of the connection portions 53 may be arbitrarily determined as long as the lead portions 51 can be stably supported by the frame portion N5, and are preferably arranged in the vicinity of the corners of the substantially rectangular lead portions 51.

The terminal row 52 has supporting portions 523 arranged at predetermined intervals in order from the left side of fig. 5 (a)₁To 523₄And a connecting portion 522₁And a connecting portion 522₂And a support portion 523₅. The lead part 51, the connection part 53, and the frame part N5 are thin plate parts formed to a predetermined thickness, and the connection part 522₁And a connecting portion 522₂And a support portion 523₁To 523₅The thick plate portion is formed to have the same thickness as the thickness of the lead wire portion 51. Coupling portion 522₁And a connecting portion 522₂And a support portion 523₁To 523₅For example, the shape of the connection portion 122, the terminal portion 121, and the support portion 123 in plan view₁To 123₅Have the same shape in plan view.

The lead portion 51, the connection portion 53, and the upper surface (the surface on the sixth metal plate 60 side) of the frame portion N5 and the connection portion 522₁And a connecting portion 522₂And, andsupport portion 523₁To 523₅The upper surfaces (surfaces on the sixth metal plate 60 side) of the first and second metal plates are located on substantially the same plane. On the other hand, the lower surfaces of the lead wire portion 51, the connection portion 53, and the frame portion N5 are positioned relative to the connection portion 522₁And a connecting portion 522₂And a support portion 523₁To 523₅The lower surface of (b) is a position recessed toward the sixth metal plate 60 side.

The frame portion N5 may include a first portion having the same thickness as the lead portion 51 and a second portion having the same thickness as the thick plate portion constituting the terminal row 52. For example, as the second portion, in order to prevent the metal plates from inclining while securing the joint with the adjacent metal plates, the reinforcing portions 54 may be provided at the four corners of the frame portion N5. In this case, the lower surface of the reinforcing portion 54 is positioned at the connection portion 522₁Etc. are substantially coplanar. The reinforcing portion 54 may be formed in an L-shape, for example. In order to prevent the inclination of the metal plates while making the joining with the adjacent metal plates firm, a second portion (thick plate portion) may be provided in a portion other than the corner portion of the frame portion N5 instead of the reinforcing portion 54 or in addition to the reinforcing portion 54.

The thickness of the lead portion 51, the connection portion 53, and the frame portion N5 is the same as the thickness of the lead portion 11, and the connection portion 522₁And a connecting portion 522₂And a support portion 523₁To 523₅For example, the thickness of (2) is the same as that of the terminal portion 121.

Coupling portion 522₁And 522₂Is disposed inside the product region M5, and one side thereof extends to the outside of the product region M5 and is connected to the frame portion N5. Self-coupling portion 522₁And 522₂The extended portion is a thin plate portion identical to the connecting portion 53. Coupling portion 522₁The other side of the lead portion 51 is connected to the starting point 511 of the lead portion 51. Coupling portion 522₂The other side of the lead portion 51 is connected to the end point 512 of the lead portion 51.

Support portion 523₁To 523₅Is disposed inside the product region M5, and one side thereof extends to the outside of the product region M5 and is connected to the frame portion N5. Self-supporting portion 523₁To 523₅The extended portion is a thin plate portion identical to the connecting portion 53. Support portion 523₁To 523₅The other side of the lead wire portion 51 is not connected. That is, the support portion 523₁To 523₅And is not electrically conducted to the lead portion 51. In this way, in the terminal row 52 of the fifth metal plate 50, the thick plate portions (the connection portions 522) connected to both ends of the lead portions 51 are formed₁And 522₂) The other thick plate portions are electrically independent from the lead portions 51, and serve as support portions for the thick plate portions supporting the terminal rows of the other metal plates.

As shown in fig. 5 (b), the sixth metal plate 60 differs from the fifth metal plate 50 in that the connection portions between the start and end points of the lead portions and the terminal rows are shifted by one position to the right with respect to the fifth metal plate 50, and has the same overall shape and thickness as the fifth metal plate 50.

Specifically, the product area M6 of the sixth metal plate 60 includes the lead portion 61 formed in a substantially rectangular spiral shape, and the terminal row 62 arranged in a predetermined direction outside the spiral formed by the lead portion 61. The lead portion 61 is connected to the frame portion N6 by a plurality of connecting portions 63 (6 in this example) extending from the inside of the product area M6 to the outside of the product area M6. The number and connection positions of the connection portions 63 may be arbitrarily determined as long as the lead portions 61 can be stably supported by the frame portion N6, and are preferably arranged in the vicinity of the corners of the substantially rectangular lead portions 61.

The terminal row 62 has support portions 623 arranged at predetermined intervals in order from the left side of fig. 5 (b)₁To 623₅A connecting portion 622, and a terminal portion 621. The lead portion 61, the connection portion 63, and the frame portion N6 are thin plate portions formed to have a predetermined thickness, and the terminal portion 621, the connection portion 622, and the support portion 623₁To 623₅Is a thick plate portion formed to have the same thickness as the thickness of the lead portion 61. Terminal 621, connection portion 622, and support portion 623₁To 623₅For example, the shape of the connection portion 122, the terminal portion 121, and the support portion 123 in plan view₁To 123₅Have the same shape in plan view.

The upper surfaces (the surfaces opposite to the fifth metal plate 50) of the lead portions 61, the connection portions 63, and the frame portion N6, the terminal portions 621, the connection portions 622, and the support portions 623₁To 623₅The upper surfaces (the surfaces on the opposite side to the fifth metal plate 50) of (b) are located on substantially the same plane. On the other hand, the lower surfaces of the lead portion 61, the connection portion 63, and the frame portion N6 are positioned opposite to the terminal portion 621, the connection portion 622, and the support portion 623₁To 623₅The lower surface thereof is recessed toward the side opposite to the fifth metal plate 50.

The frame portion N6 may include a first portion having the same thickness as the lead portion 61 and a second portion having the same thickness as the thick plate portion constituting the terminal row 62. For example, as the second portion, in order to prevent the metal plates from inclining while securing the joint with the adjacent metal plates, the reinforcing portions 64 may be provided at the four corners of the frame portion N6. In this case, the lower surface of the reinforcing portion 64 is located on substantially the same plane as the lower surface of the coupling portion 622 and the like. The reinforcing portion 64 may be formed in an L-shape, for example. In order to prevent the metal plates from inclining while securing the joint with the adjacent metal plates, a second portion (thick plate portion) may be provided in place of the reinforcing portion 64 or in addition to the reinforcing portion 64 in a portion other than the corner portion of the frame portion N6.

The thickness of the lead portion 61, the connecting portion 63, and the frame portion N6 is the same as that of the lead portion 11, etc., and the terminal portion 621, the connecting portion 622, and the supporting portion 623 are formed, for example₁To 623₅For example, the thickness of (2) is the same as that of the terminal portion 121.

The connecting portion 622 is disposed inside the product region M6, and one side thereof extends outside the product region M6 and is connected to the frame portion N6. The portion extending from the coupling portion 622 is a thin plate portion similar to the coupling portion 63. The other side of the connection portion 622 is connected to the starting point 611 of the lead portion 61. The terminal portion 621 is disposed inside the product area M6, and one side thereof extends to the outside of the product area M6 and is connected to the frame portion N6. The portion extending from the terminal portion 621 is a thin plate portion like the connecting portion 63. The other side of the terminal portion 621 is connected to the end point 612 of the lead portion 61.

Support 623₁To 623₅Is disposed inside the product region M6, and one side thereof extends to the outside of the product region M6 and is connected to the frame portion N6. Self-supporting portion 623₁To 623₅The extended portion being the same as the connecting portion 63A thin plate portion. Support 623₁To 623₅The other side of the lead wire portion 61 is not connected. That is, the support portion 623₁To 623₅And is not electrically conducted to the lead portion 61. In this way, in the terminal row 62 of the sixth metal plate 60, the thick plate portions other than the thick plate portions (the connecting portion 622 and the terminal portion 621) connected to both ends of the lead portion 61 are electrically independent from the lead portion 61, and serve as support portions for supporting the thick plate portions of the terminal rows of the other metal plates.

Fig. 7 (a) is a cross-sectional view of the coil structure 1 taken along the line a-a in fig. 3 (a). Fig. 7 (B) is a cross-sectional view of the coil structure 1 taken along the line B-B in fig. 3 (a). Fig. 8 (a) is a cross-sectional view of the coil structure 1 taken along the line C-C in fig. 3 (a). Fig. 8 (b) is a cross-sectional view of the coil structure 1 taken along the line D-D in fig. 3 (a). Fig. 9 (a) is a cross-sectional view of the coil structure 1 taken along the line E-E in fig. 3 (a). Fig. 9 (b) is a cross-sectional view of the coil structure 1 taken along the line F-F in fig. 3 (a). Fig. 10 is a cross-sectional view of the coil structure 1 taken along the line G-G in fig. 3 (a). In fig. 7 to 10, for convenience, some reference numerals are omitted.

Referring to fig. 7 to 10 in addition to fig. 1 to 6, in the coil structure 1, adjacent metal plates are joined to each other. The adjacent metal plates may be joined to each other by, for example, diffusion bonding. Diffusion bonding is preferable in that the upper and lower metal plates can be bonded without interposing a material having different electrical conductivity and thermal conductivity, such as solder, and thus a voltage loss occurring in the bonding portion can be reduced.

Specifically, the terminal row 22 of the second metal plate 20 is laminated over the terminal row 12 of the first metal plate 10, and both are joined to each other. That is, the support portion 223 is stacked on the terminal portion 121₁A connecting part 222 is laminated on the connecting part 122₁At the supporting part 123₁On which a connection part 222 is laminated₂At the supporting part 123₂On which a support part 223 is laminated₂At the supporting part 123₃On which a support part 223 is laminated₃At the supporting part 123₄On which a support part 223 is laminated₄At the supporting part 123₅Thereon is laminated withSupport 223₅. Further, each reinforcing portion 24 is joined to each reinforcing portion 14.

Thereby, the connection portion 122 connected to the end point 112 of the lead portion 11 and the connection portion 222 connected to the start point 211 of the lead portion 21₁Conduction is established, and the lead portion 11 and the lead portion 21 are connected in series. Since the lead portions 11 and 21 are formed thinner than the terminal rows 12 and 22, the upper surfaces of the lead portions 11 and the lower surfaces of the lead portions 21 do not contact each other. Further, since any one of the thick plate portions of the terminal row 12 is surely disposed below each of the thick plate portions of the terminal row 22, the upper and lower metal plates can be easily joined to each other.

Likewise, the terminal row 32 of the third metal plate 30 is laminated over the terminal row 22 of the second metal plate 20, and both are joined to each other. That is, at the support portion 223₁On which a support part 323 is laminated₁At the connecting part 222₁On which a support part 323 is laminated₂At the connecting part 222₂On which a connecting part 322 is laminated₁At the supporting part 223₂On which a connecting part 322 is laminated₂At the supporting part 223₃On which a support part 323 is laminated₃At the supporting part 223₄On which a support part 323 is laminated₄At the supporting part 223₅On which a support part 323 is laminated₅. Further, the reinforcing portions 34 are joined to the reinforcing portions 24.

Thereby, the connection portion 222 connected to the end point 212 of the lead portion 21₂A connection part 322 connected to the starting point 311 of the lead part 31₁When the lead portion 21 and the lead portion 31 are electrically connected to each other, they are connected in series. Since the lead portions 21 and 31 are formed thinner than the terminal rows 22 and 32, the upper surfaces of the lead portions 21 and the lower surfaces of the lead portions 31 do not contact each other. Further, since any one of the thick plate portions of the terminal row 22 is surely disposed below each of the thick plate portions of the terminal row 32, the upper and lower metal plates can be easily joined to each other.

Likewise, the terminal row 42 of the fourth metal plate 40 is laminated over the terminal row 32 of the third metal plate 30, and both are joined to each other. That is, at the supporting portion 323₁A supporting part is laminated on the upper layer423₁At the supporting part 323₂On which a supporting part 423 is laminated₂At the connecting part 322₁On which a supporting part 423 is laminated₃At the connecting part 322₂On which a connection part 422 is laminated₁At the supporting part 323₃On which a connection part 422 is laminated₂At the supporting part 323₄On which a supporting part 423 is laminated₄At the supporting part 323₅On which a supporting part 423 is laminated₅. Further, the reinforcing portions 44 are joined to the reinforcing portions 34.

Thereby, the connection portion 322 connected to the end point 312 of the lead portion 31₂And a connection part 422 connected to the starting point 411 of the lead part 41₁Conduction is established, and the lead portion 31 and the lead portion 41 are connected in series. Since the lead portions 31 and 41 are formed thinner than the terminal rows 32 and 42, the upper surfaces of the lead portions 31 and the lower surfaces of the lead portions 41 do not contact each other. Further, since any one of the thick plate portions of the terminal row 32 is surely disposed below each of the thick plate portions of the terminal row 42, the upper and lower metal plates can be easily joined to each other.

Likewise, the terminal row 52 of the fifth metal plate 50 is laminated over the terminal row 42 of the fourth metal plate 40, and both are joined to each other. That is, the support part 423₁A support portion 523 is laminated thereon₁At the supporting part 423₂A support portion 523 is laminated thereon₂At the supporting part 423₃A support portion 523 is laminated thereon₃At the connection part 422₁A support portion 523 is laminated thereon₄At the connection part 422₂On which a connection part 522 is laminated₁At the supporting part 423₄On which a connection part 522 is laminated₂At the supporting part 423₅A support portion 523 is laminated thereon₅. Further, the reinforcing portions 54 are joined to the reinforcing portions 44.

Thereby, the connection portion 422 connected to the end point 412 of the lead portion 41₂A connection portion 522 connected to the starting point 511 of the lead portion 51₁Conduction is established, and the lead portion 41 and the lead portion 51 are connected in series. In addition, since the lead portions 41 and 51 are formed thinner than the terminal rows 42 and 52, the lead portions 41 are formed ofThe upper surface is not intended to be in contact with the lower surface of the lead portion 51. Further, since any one of the thick plate portions of the terminal row 42 is surely disposed below each of the thick plate portions of the terminal row 52, the upper and lower metal plates can be easily joined to each other.

Likewise, the terminal row 62 of the sixth metal plate 60 is laminated over the terminal row 52 of the fifth metal plate 50, and both are joined to each other. Namely, at the support portion 523₁On which a support portion 623 is laminated₁At the supporting part 523₂On which a support portion 623 is laminated₂At the supporting part 523₃On which a support portion 623 is laminated₃At the supporting part 523₄On which a support portion 623 is laminated₄At the connection portion 522₁On which a support portion 623 is laminated₅At the connection portion 522₂A connecting portion 622 is laminated on the upper side, and a supporting portion 523₅A terminal portion 621 is stacked thereon. Further, the reinforcing portions 64 are joined to the reinforcing portions 54.

Thereby, the connection portion 522 connected to the end point 512 of the lead portion 51₂The lead portion 51 is connected in series with the lead portion 61 by being connected to the connection portion 622 connected to the starting point 611 of the lead portion 61. Since the lead portions 51 and 61 are formed thinner than the terminal rows 52 and 62, the upper surfaces of the lead portions 51 and the lower surfaces of the lead portions 61 do not contact each other. Further, since any one of the thick plate portions of the terminal row 52 is surely disposed below each of the thick plate portions of the terminal row 62, the upper and lower metal plates can be easily joined to each other.

With the above configuration, in the coil structure 1, the end point 112 of the lead portion 11 and the start point 211 of the lead portion 21, the end point 212 of the lead portion 21 and the start point 311 of the lead portion 31, the end point 312 of the lead portion 31 and the start point 411 of the lead portion 41, the end point 412 of the lead portion 41 and the start point 511 of the lead portion 51, and the end point 512 of the lead portion 51 and the start point 611 of the lead portion 61 are sequentially connected. Thereby, one spiral coil is formed from the start point 111 of the lead portion 11 to the end point 612 of the lead portion 61.

Fig. 11 and 12 are views illustrating a manufacturing process of the coil structure according to the first embodiment. Fig. 11 and 12 are cross-sectional views corresponding to line B-B of fig. 3 (a), and only one product region is illustrated.

First, in the step shown in fig. 11 (a), a plate-like metal 100 having a constant thickness and having a planar shape shown in fig. 1 (a) is prepared. The plate-like metal 100 is a member that ultimately becomes the first metal plate 10, and is formed of, for example, copper, a copper alloy, a Fe — Ni alloy such as 42 alloy, or the like. The thickness of the plate-like metal 100 may be set to, for example, about 50 μm to 500 μm. A plurality of product regions are defined in the sheet-shaped metal 100, and then the resist layer 310 is formed on the entire upper surface of the sheet-shaped metal 100, and the resist layer 320 is formed on the entire lower surface of the sheet-shaped metal 100. The resist layers 310 and 320 can be formed by, for example, laminating a photosensitive dry film resist.

Next, in the step shown in fig. 11 (b), the resist layer 310 is exposed and developed, thereby forming an opening 310x that selectively exposes the upper surface of the plate-like metal 100. The resist layer 320 is exposed and developed to form an opening 320x that selectively exposes the lower surface of the plate-like metal 100.

Next, in the step shown in fig. 11(c), the plate-like metal 100 exposed in the opening 310x is half-etched from the upper surface side, and the plate-like metal 100 exposed in the opening 320x is half-etched from the lower surface side. Thus, the plate-like metal 100 is patterned to form the first metal plate 10 having the lead portions 11, the terminal rows 12, and the like.

In the plate-like metal 100, the region where the resist layer 310 and the resist layer 320 overlap in a plan view has an original thickness because it is not etched, and this portion becomes a thick plate portion. In addition, the regions where the resist layers 310 and 320 are not formed in a plan view are half-etched from both surfaces to penetrate. In addition, the region where only the resist layer 310 is formed in a plan view is half-etched only from the lower surface side, and becomes a thin plate portion having a thickness of about half of the first thickness. In the case where the plate-like metal 100 is copper, an iron chloride solution, for example, may be used for half etching.

Next, in the step (a) shown in fig. 12, the second metal plate 20, the third metal plate 30, the fourth metal plate 40, the fifth metal plate 50, and the sixth metal plate 60 are produced by the same method as in fig. 11 (a) to 11 (c). The shapes of the metal plates in plan view are as shown in fig. 3 (b) to 5 (b), and the sectional shapes of the metal plates are as shown in fig. 6 to 10.

Next, in the step shown in fig. 12 (b), the metal plates are stacked, and thick plate portions including the terminal rows of the adjacent metal plates are joined to each other. Specifically, the metal plates are laminated in the order shown in fig. 12 (b) to form a laminate, and the laminate is pressed and heated in the vertical direction in a vacuum atmosphere to perform diffusion bonding. Thereby, the thick plate portions of the adjacent metal plates are directly joined to each other, and the coil structure 1 is completed. In the diffusion bonding, any one of the thick plate portions of the lower terminal row is always arranged below each of the thick plate portions except for the lowermost terminal row, and therefore, the thick plate portions can be bonded together. It is preferable that the materials of the metal plates are set to be the same, so that the adjacent metal plates can be favorably joined to each other by diffusion bonding.

The coil structure 1 is completed through the above steps, and the inductor 2 can be manufactured by continuing the steps of fig. 13.

In the step shown in fig. 13 (a), a sealing resin 70 is formed on the coil structure 1 shown in fig. 12 (b). As the insulating resin constituting the sealing resin 70, for example, thermosetting resins such as epoxy resins, polyimide resins, phenol resins, and acrylic resins, and thermoplastic resins can be used. The sealing resin 70 is formed such that the lower surfaces of the terminal rows 12 of the first metal plate 10 are exposed on the lower surface of the sealing resin 70. It is preferable that after the sealing resin 7 is formed, the lower surface of the sealing resin 70 is ground or shot-blasted to remove resin burrs on the lower surface of the terminal row 12. A low-pressure molding method such as transfer molding, compression molding, or the like may be used for the formation of the sealing resin 70.

Next, in the step shown in fig. 13 (b), the structure shown in fig. 13 (a) is cut at the position of the cutting line L using a dicing blade or the like and singulated to produce the inductor 2. The structure shown in fig. 13 (a) may be singulated by pressing or etching. The cutting line L corresponds to a broken line indicating the product region M in fig. 1 (b). By cutting, the side surfaces of the terminal rows 12, 22, 32, 42, 52, and 62 are exposed from one side surface of the sealing resin 70. The surface-mount inductors 2 shown in fig. 14 (a) and 14 (b) are formed in the respective product areas M. The inductor 2 has a rectangular shape such as a square shape or a rectangular shape in a plan view.

Side surfaces and lower surfaces of terminal portions 121 of terminal row 12 exposed from sealing resin 70, and support portions 223 of terminal row 22₁Side surface of (2), and support part 323 of terminal row 32₁Side surface of (3), and support portion 423 of terminal row 42₁Side surface of (3), and support portion 523 of terminal row 52₁Side surface of (1), and support portion 623 of terminal row 62₁Becomes the external connection terminal 1A. Further, the support portions 123 of the terminal rows 12 exposed from the sealing resin 70₅Side surfaces and lower surfaces of (1), and support portions 223 of terminal rows 22₅Side surface of (2), and support part 323 of terminal row 32₅Side surface of (3), and support portion 423 of terminal row 42₅Side surface of (3), and support portion 523 of terminal row 52₅The side surface of the terminal row 62 and the side surface of the terminal portion 621 of the terminal row 62 become the external connection terminal 1B.

Fig. 14 (b) is a view of fig. 14 (a) as viewed from the lower surface side. In other words, fig. 14 (b) is a view in which fig. 14 (a) is rotated 180 degrees in the left-right direction of the paper surface and the top and bottom are inverted. The inductor 2 may have a substantially rectangular shape, for example, approximately 3mm × 3mm in plan view. The thickness of the inductor 2 may be set to, for example, about 1.0 mm.

Fig. 15 is a sectional view for explaining a method of mounting an inductor according to the first embodiment, in which fig. 15 (a) shows a section H of fig. 14, and fig. 15 (b) shows a section I of fig. 14. In fig. 15 (a) and 15 (b), the inductor 2 is mounted on the substrate 200. Specifically, a pad 210 is formed on one surface of substrate 200, and a part of the upper surface of pad 210 is exposed in opening 220x of solder resist layer 220. The upper surface of the pad 210 exposed in the opening 220x is electrically connected to the external connection terminals 1A and 1B of the inductor 2 by solder 230.

Thus, the coil structure 1 has a structure in which 6 metal plates are stacked. Each metal plate includes a helical lead portion and a terminal row in which 7 thick plate portions formed to be thicker than the lead portion and having the same thickness are arranged in a predetermined direction outside a helix formed by the lead portion, and the metal plates are stacked, and the terminal rows of adjacent metal plates are joined to each other. In addition, both ends of the lead portion of each metal plate are connected to any two thick plate portions adjacent to each other among the thick plate portions constituting the terminal row of each metal plate.

Both ends of the lead portion 11 in the lowermost layer are connected to the terminal portions 121 and the connecting portion 122, which are two thick plate portions on one end side (left side in fig. 3 a and the like) of the terminal row 12, and the positions of the thick plate portions connected to both ends of the lead portion in each layer are shifted one position toward the other end side of the terminal row. With this structure, the lead portions of the respective metal plates are connected in series to form one helical coil.

In such a configuration, it is easy to increase the number of windings of the coil by increasing the number of laminations of the metal plates. As a result, by using the coil structure 1, the inductor 2 which is small and can obtain a large induced electromotive force can be realized. That is, by sealing the coil structure 1 with the sealing resin 70 so as to expose the external connection terminals 1A and 1B, the inductor 2 can be realized which is small in size and can obtain a large induced electromotive force.

The number of metal plates to be stacked is not limited to 6, and n (n is a natural number of 2 or more) plates may be used. In this case, each metal plate may include a helical lead portion and a terminal row in which n +1 thick plate portions formed to be thicker than the lead portion and having the same thickness are arranged in a predetermined direction outside a helix formed by the lead portion. Alternatively, the number of thick plate portions constituting the terminal row may be n +1 or more. For example, when the number of metal plates is changed to n +1 or more, the number of thick plate portions constituting the terminal row may be n +1 or more.

For example, if it is assumed that the number of thick plate portions constituting the terminal row is n or less in the case of stacking n metal plates, there are thick plate portions which are not supported from below and are in a suspended state in the case of bonding the metal plates by applying heat and pressure from above and below, and bonding at these portions becomes difficult.

In contrast, in the coil structure 1, in the structure in which n metal plates are stacked, each metal plate is provided with a terminal row in which n +1 thick plate parts are arranged in a predetermined direction outside a spiral formed by the lead parts. Therefore, the respective metal plates can be easily joined by diffusion bonding or the like.

In the coil structure 1, the 6 thick plate portions stacked at one end of the terminal row serve as the external connection terminals 1A, and the 6 thick plate portions stacked at the other end of the terminal row serve as the external connection terminals 1B. That is, the supporting portion 223 is above the terminal portion 121₁、323₁、423₁、523₁And 623₁The external connection terminals 1A are stacked in this order. In addition, at the supporting portion 123₅Above, the supporting part 223₅、323₅、423₅、523₅And the terminal portion 621 are stacked in this order to constitute the external connection terminal 1B.

In the external connection terminal 1A, one end sides of the terminal rows of the respective metal plates are stacked on the terminal portions 121 of the first metal plate 10 and electrically connected to each other, and therefore, connection to the outside can be made in any layer of the external connection terminal 1A. Similarly, the external connection terminal 1B is supported by the support portion 123 of the first metal plate 10₅Since the other end sides of the terminal rows of the respective metal plates are stacked and electrically connected to each other, connection to the outside can be made at any layer of the external connection terminal 1B.

In the above description, for convenience, the lead portion 11 side is set as the starting point and the lead portion 61 side is set as the end point, but the coil structure 1 is nonpolar, and a current may flow from the external connection terminal 1A to the external connection terminal 1B or from the external connection terminal 1B to the external connection terminal 1A.

The coil structure 1 may be shipped as a product, or the inductor 2 may be shipped as a product. Further, at least one of the first metal plate 10, the second metal plate 20, the third metal plate 30, the fourth metal plate 40, the fifth metal plate 50, and the sixth metal plate 60 before lamination may be shipped as a lead frame. That is, a lead frame including a spiral lead portion and a terminal row in which 3 or more thick plate portions formed to have the same thickness as the lead portion are arranged in a predetermined direction outside the spiral formed by the lead portion, and both ends of the lead portion are connected to any two thick plate portions constituting the terminal row may be shipped.

< modification 1 of the first embodiment >

In modification 1 of the first embodiment, an example is shown in which the lead portions and the like are covered with an insulating film. In modification 1 of the first embodiment, a description of the same components as those of the above-described embodiment may be omitted.

Fig. 16 is a cross-sectional view illustrating a coil structure according to modification 1 of the first embodiment, and shows a cross-section corresponding to fig. 7 (b). Referring to fig. 16, the coil structure 3 is different from the coil structure 1 (see fig. 7 (b) and the like) in that an insulating film 80 is formed to cover the surfaces of the metal plates.

Specifically, the insulating film 80 is formed on the surfaces of the lead portion 11, the connection portion 13, the frame portion N1 of the first metal plate 10, the lead portion 21, the connection portion 23, the frame portion N2 of the second metal plate 20, the lead portion 31, the connection portion 33, the frame portion N3 of the third metal plate 30, the lead portion 41, the connection portion 43, the frame portion N4, the lead portion 51, the connection portion 53, the frame portion N5 of the fifth metal plate 50, and the lead portion 61, the connection portion 63, and the frame portion N6 of the sixth metal plate 60. Further, an insulating film 80 is formed on each surface of a laminate in which the terminal row 12, the terminal row 22, the terminal row 32, the terminal row 42, the terminal row 52, and the respective portions (terminal portion, coupling portion, and support portion) of the terminal row 62 are laminated.

As a material of the insulating film 80, for example, an insulating resin such as an epoxy resin or a polyimide resin can be used. The thickness of the insulating film 80 may be set to, for example, about 10 μm. The insulating film 80 may be formed by, for example, an electrodeposition method. By forming the insulating film 80 by an electrodeposition method, an insulating film having a substantially uniform thickness can be formed on the surface of each metal plate.

Fig. 17 is a sectional view showing an inductor according to modification 1 of the first embodiment by way of example. As shown in fig. 17, the inductor 4 can be formed by sealing the coil structure 3 shown in fig. 16 with a sealing resin 71 and cutting the same at a predetermined position. The inductor 4 has a rectangular shape such as a square shape or a rectangular shape in plan view. As the sealing resin 71, for example, an insulating resin containing a filler of a magnetic material can be used.

As the filler of the magnetic body, for example, powder of a soft magnetic body can be used. Examples of the powder of the soft magnetic material include powders of an iron-based amorphous alloy, carbonyl iron powder, and powders of ferrite, permalloy, and the like. Examples of the insulating resin include thermosetting resins such as epoxy resins, polyimide resins, phenol resins, and acrylic resins, and thermoplastic resins. By adjusting the mixing ratio of the filler of the magnetic material and the insulating resin, necessary permeability and moldability can be ensured.

In order to produce the inductor 4, for example, after an insulating film 80 is formed by an electrodeposition method or the like on the surface of each metal plate of the structure shown in fig. 12 (b), a sealing resin 71 is formed by a low-pressure molding method such as a transfer molding method or a compression molding method as shown in fig. 18 (a). As shown in fig. 18 (b), the insulating film 80 covering the lower surface side of the structure shown in fig. 18 (a) is removed by grinding or shot blasting, and the lower surfaces of the terminal rows 12 are exposed from the sealing resin 71. Thereafter, the structure shown in fig. 18 (b) is cut at the position of the cutting line L by using a dicing blade or the like to be singulated, thereby producing the inductor 4, as in the step (b) of fig. 13. From each product region M, the surface-mount inductor 4 shown in fig. 19 (a) and 19 (b) is fabricated. Fig. 19 (b) is a view of fig. 19 (a) as viewed from the lower surface side. In other words, fig. 19 (b) is a view in which fig. 19 (a) is rotated 180 degrees in the left-right direction of the paper surface and is inverted in the up-down direction. The inductor 4 may have a substantially rectangular shape, for example, approximately 3mm × 3mm in plan view. The thickness of the inductor 4 may be set to, for example, about 1.0 mm.

Fig. 20 is a sectional view for explaining a method of mounting an inductor according to modification 1 of the first embodiment, in which fig. 20 (a) shows a section H of fig. 19 and fig. 20 (b) shows a section I of fig. 19. In fig. 20 (a) and 20 (b), the inductor 4 is mounted on the substrate 200. Specifically, a pad 210 is formed on one surface of substrate 200, and a part of the upper surface of pad 210 is exposed in opening 220x of solder resist layer 220. The upper surface of the pad 210 exposed in the opening 220x is electrically connected to the external connection terminals 1A and 1B of the inductor 4 by solder 230.

In this way, in the inductor 4, the inductance of the inductor 4 can be improved by sealing the coil structure 3 with the sealing resin 71 made of an insulating resin containing a filler of a magnetic material. Further, by covering the surface of each metal plate with the insulating film 80, it is possible to prevent the adjacent metal plates from being electrically connected to each other via the filler.

Although the preferred embodiments and the like have been described above in detail, the embodiments and the like are not limited to the above embodiments and the like, and various modifications and substitutions may be made thereto without departing from the scope of the claims.

For example, the shape of the lead portions and the frame portion of each metal plate in a plan view is not limited to a substantially rectangular shape, and may be a circular shape, an elliptical shape, or other more complicated shapes.