Coil structure, method of manufacturing the same, lead frame, and inductor

Abstract

Provided is a coil structure that can obtain a large induced electromotive force. The coil structure is formed by stacking a plurality of metal plates, each of which includes a spiral wire portion, an end portion thick plate portion formed thicker than the wire portion at both ends of the wire portion, and an inner side thick plate portion formed to the same thickness as the end portion thick plate portion and arranged separately from the wire portion on the inner side of the spiral formed by the wire portion. The coil structure is formed by stacking the metal plates, joining one of the end portion thick plate portions of adjacent metal plates to each other, forming a spiral coil in which the wire portions of the metal plates are connected in series, and joining the inner side thick plate portions of adjacent metal plates to each other to form a magnetic core.

Description

TECHNICAL FIELD

[0001] The present application relates to a coil structure and a manufacturing method thereof, a lead frame, and an inductor. BACKGROUND

[0002] In a circuit, an inductor is sometimes used for the purpose of stabilization of current or conversion of voltage, and the like. In recent years, miniaturization of electronic devices such as game machines or smartphones is accelerating, and in conjunction therewith, miniaturization of inductors mounted on such electronic devices is also required, and surface-mount type inductors have been proposed.

[0003] As an inductor mounted on such an electronic device, for example, a structure can be cited in which a coil structure having a winding formed of a relatively thin metal plate is encapsulated with a resin.

[0004] <Related Art>

[0005] <Patent Literature>

[0006] Patent Literature 1: Japanese Patent Application Publication No. 2020-027820 SUMMARY

[0007] <Problems to be Solved by the Invention>

[0008] However, it is difficult to obtain a large induced electromotive force in a coil structure having a winding formed of a relatively thin metal plate.

[0009] In view of the above problem, an object of the present application is to provide a coil structure capable of obtaining a large induced electromotive force.

[0010] <Means for Solving the Problems>

[0011] The present coil structure is formed by stacking a plurality of metal plates, wherein each of the metal plates includes a spiral-shaped conductor portion, an end portion thick plate portion formed thicker than the conductor portion at both ends of the conductor portion, and an inner side thick plate portion formed to the same thickness as the end portion thick plate portion and arranged separately from the conductor portion on the inner side of the spiral formed by the conductor portion, the plurality of metal plates are stacked, one of the end portion thick plate portions of adjacent metal plates are joined to each other, a spiral-shaped coil in which the conductor portions of the plurality of metal plates are connected in series is formed, and the inner side thick plate portions of adjacent metal plates are joined to each other to form a magnetic core.

[0012] <EFFECTS OF THE INVENTION>

[0013] According to the disclosed technology, a coil structure capable of obtaining a large induced electromotive force can be provided. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 is a plan view showing the coil structure according to the first embodiment.

[0015] Figure 2 is Figure 1 is a perspective view of one product region of (a).

[0016] Figure 3 is a plan view showing the vicinity of the product region of each metal plate before lamination (1 thereof).

[0017] Figure 4 is a plan view showing the vicinity of the product region of each metal plate before lamination (2 thereof).

[0018] Figure 5 is a plan view showing the vicinity of the product region of each metal plate before lamination (3 thereof).

[0019] Figure 6 is a sectional view of the first metal plate 10 along lines A-A to K-K.

[0020] Figure 7 is a sectional view of the coil structure 1 along Figure 3 lines A-A and B-B of (a).

[0021] Figure 8 is a sectional view of the coil structure 1 along Figure 3 lines C-C and D-D of (a).

[0022] Figure 9 is a sectional view of the coil structure 1 along Figure 3 lines E-E and F-F of (a).

[0023] Figure 10 is a sectional view of the coil structure 1 along Figure 3 lines G-G and H-H of (a).

[0024] Figure 11 is a sectional view of the coil structure 1 along Figure 3 lines I-I and J-J of (a).

[0025] Figure 12 is a sectional view of the coil structure 1 along Figure 3 line K-K of (a).

[0026] Figure 13 is a view showing the manufacturing process of the coil structure according to the first embodiment (1 thereof).

[0027] Figure 14 is a view showing the manufacturing process of the coil structure according to the first embodiment (2 thereof).

[0028] Figure 15 is a view showing a manufacturing process of an inductor according to the first embodiment.

[0029] Figure 16 is a perspective view showing an inductor according to the first embodiment.

[0030] Figure 17 is a sectional view for explaining a mounting method of an inductor according to the first embodiment.

[0031] Figure 18 is a plan view showing a coil structure according to Modification 1 of the first embodiment.

[0032] Figure 19 is a plan view (1 thereof) showing the vicinity of a product region of each metal plate before lamination.

[0033] Figure 20 is a plan view (2 thereof) showing the vicinity of a product region of each metal plate before lamination.

[0034] Figure 21 is a sectional view of the first metal plate 70 along lines A-A to I-I.

[0035] Figure 22 is a sectional view of the coil structure 3 along lines A-A and B-B of (a). Figure 19

[0036] Figure 23 is a sectional view of the coil structure 3 along lines C-C and D-D of (a). Figure 19

[0037] Figure 24 is a sectional view of the coil structure 3 along lines E-E and F-F of (a). Figure 19

[0038] Figure 25 is a sectional view of the coil structure 3 along lines G-G and H-H of (a). Figure 19

[0039] Figure 26 is a sectional view of the coil structure 3 along line I-I of (a). Figure 19

[0040] Figure 27 is a perspective view showing an inductor according to Modification 1 of the first embodiment.

[0041] Figure 28 is a sectional view for explaining a mounting method of an inductor according to Modification 1 of the first embodiment.

[0042] Explanation of Reference Numerals ​​​​​

[0043] 1, 3 Coil structure

[0044] 1A, 1B External connection terminal

[0045] 2, 4 Inductor

[0046] 10, 70 First metal plate

[0047] 11, 21, 31, 41, 51, 61, 71, 81, 91 Lead portion

[0048] 12, 62, 72, 92 Terminal portion

[0049] 13, 231, 232, 331, 332, 431, 432, 531, 532, 63 Connecting portion

[0050] 14, 24, 34, 44, 54, 64, 74, 84, 94 Core

[0051] 151 to 156, 251 to 256, 351 to 356, 451 to 456, 551 to 556, 651 to 656, 751, 752, 851, 852, 951, 952 Supporting portion

[0052] 16, 26, 36, 46, 56, 66, 76, 86, 96 Connecting portion

[0053] 17, 27, 37, 47, 57, 67, 77, 87, 97 Core connecting portion

[0054] 18, 28, 38, 48, 58, 68, 78, 88, 98 Reinforcing portion

[0055] 20, 80 Second metal plate

[0056] 30, 90 Third metal plate

[0057] 40 Fourth metal plate

[0058] 50 Fifth metal plate

[0059] 60 Sixth metal plate

[0060] 150 Encapsulation resin

[0061] 111, 211, 311, 411, 511, 611, 711, 811, 911 Starting point

[0062] 112, 212, 312, 412, 512, 612, 712, 812, 912 End point DETAILED DESCRIPTION

[0063] Embodiments of the present application will be described below with reference to the accompanying drawings. Note that, in the drawings, the same portions will be denoted by the same reference signs, and repetitive description will be omitted at times.

[0064] <Embodiment 1>

[0065] Figure 1 is a plan view showing a coil structure according to Embodiment 1, Figure 1 (a) is an overall view, Figure 1 (b) is Figure 1 is an enlarged view of the vicinity of one product region M of (a). Figure 2 is Figure 1 is a perspective view of one product region of (a), Figure 2 (a) shows a state with a magnetic core portion, Figure 2 (b) shows a state in which the magnetic core portion is removed for convenience. In addition, the coil structure 1 is a 6-layer structure in which the first metal plate to the sixth metal plate are sequentially stacked, but in Figure 2 (a) and Figure 2 (b), for convenience, 3 layers from the first metal plate to the third metal plate are shown.

[0066] As shown in Figure 1 (a), Figure 1 (b), and Figure 2 , the coil structure 1 is a structure in which two or more metal plates are stacked, and the metal plates adjacent to each other in the up-down direction are joined to each other. The number of the metal plates can be at least two, and in this case, it is a 2-layer structure, but in this embodiment, the coil structure 1 is 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.

[0067] In a plan view, the coil structure 1 has a plurality of product regions M arranged in a matrix. Each product region M is a region that constitutes an inductor after the entire coil structure 1 is resin-sealed and singulated. Around each product region M, a frame portion N in the shape of a frame that supports each product region M from the peripheral side is formed, and adjacent frame portions N are integrally formed with each other and are connected to each other. A magnetic core C is disposed at a substantially central portion of each product region M. The planar shape of the magnetic core C is, for example, a rectangular shape such as a square or a rectangle. Note that, in Figure 1 (a), as one example, 18 (3 rows x 6 columns) product regions M are arranged, but it is not limited thereto.

[0068] Figures 3-5 is a plan view showing the vicinity of the product region of each metal plate before being stacked. Specifically, Figure 3 (a) is a plan view of the first metal plate 10.Figure 3 (b) is a plan view of the second metal plate 20. Figure 4 (a) is a plan view of the third metal plate 30. Figure 4 (b) is a plan view of the fourth metal plate 40. Figure 5 (a) is a plan view of the fifth metal plate 50. Figure 5 (b) is a plan view of the sixth metal plate 60.

[0069] Note that 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 respectively the same planar shape as Figure 1 (a), Figure 3 (a) ~ Figure 5 (b) shows a portion (a portion near the product region) of each metal plate corresponding to Figure 1 (b). In addition, in Figure 3 (a) ~ Figure 5 (b), the gray portion indicates a thin plate portion, and the satin pattern portion indicates a thick plate portion formed thicker than the thin plate portion and protruding downward with respect to the thin plate portion. The thin plate portion and the thick plate portion are integrally formed.

[0070] In Figures 3-5 , among the product regions M, the product region of the first metal plate 10 is set to Ml, 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 addition, in Figures 3-5 , among the frame portions N, the frame portion of the first metal plate 10 is set to Nl, the frame portion of the second metal plate 20 is set to N2, the frame portion of the third metal plate 30 is set to N3, the frame portion of the fourth metal plate 40 is set to N4, the frame portion of the fifth metal plate 50 is set to N5, and the frame portion of the sixth metal plate 60 is set to N6.

[0071] Figure 6 is a cross-sectional view of the first metal plate 10 along the line A-A ~ the line K-K of Figure 3 (a). Specifically, Figure 6 (a) is a cross-sectional view of the first metal plate 10 along the line A-A of Figure 3 (a). Figure 6 (b) is a cross-sectional view of the first metal plate 10 along the line B-B of Figure 3 (a). Figure 6 (c) is a cross-sectional view of the first metal plate 10 along the line C-C of Figure 3 (a). Figure 6 (d) is a cross-sectional view of the first metal plate 10 along the line D-D of Figure 3 (a).Figure 6 (e) is a sectional view of the first metal plate 10 along Figure 3 (a) line E-E. Figure 6 (f) is a sectional view of the first metal plate 10 along Figure 3 (a) line F-F. Figure 6 (g) is a sectional view of the first metal plate 10 along Figure 3 (a) line G-G. Figure 6 (h) is a sectional view of the first metal plate 10 along Figure 3 (a) line H-H. Figure 6 (i) is a sectional view of the first metal plate 10 along Figure 3 (a) line I-I. Figure 6 (j) is a sectional view of the first metal plate 10 along Figure 3 (a) line J-J. Figure 6 (k) is a sectional view of the first metal plate 10 along Figure 3 (a) line K-K.

[0072] As shown in Figure 6 (a) and Figure 3 , the product area Ml of the first metal plate 10 has a lead portion 11, a terminal portion 12, a connecting portion 13, a magnetic core portion 14, and support portions 151 to 156.

[0073] The lead portion 11 is formed in a substantially rectangular spiral (substantially 3 / 4 turns) on the inner side of the product area Ml, and is connected to the frame portion Nl by a plurality of connection portions 16 (six, for example, in this case) extending from the inner side of the product area Ml to the outer side of the product area Ml. The number and connection positions of the connection portions 16 can be arbitrarily determined as long as the lead portion 11 can be stably supported by the frame portion Nl, but it is preferable to arrange them near the corners of the substantially rectangular lead portion 11.

[0074] The terminal portion 12 is formed at a starting point 111 which is one end of the lead portion 11, and the connecting portion 13 is formed at a terminal point 112 which is the other end. The planar shape of the terminal portion 12 and the connecting portion 13 is, for example, a square or a rectangle. The lead portion 11, the connection portions 16, and the frame portion Nl are thin plate portions formed to a predetermined thickness, and the terminal portion 12 and the connecting portion 13 are thick plate portions formed to the same thickness as the lead portion 11 and the like. The terminal portion 12 and the connecting portion 13 are sometimes collectively referred to as end thick plate portions.

[0075] The terminal portion 12 is arranged inside the product region Ml, and extends to the outside of the product region Ml from the opposite side of the connecting portion of the starting point 111 of the wire portion 11 and is connected to the frame portion Nl. The portion extending from the terminal portion 12 is a thin plate portion same as the connecting portion 16. The linking portion 13 is arranged inside the product region Ml, and extends to the outside of the product region Ml from the opposite side of the connecting portion of the terminal point 112 of the wire portion 11 and is connected to the frame portion Nl. The portion extending from the linking portion 13 is a thin plate portion same as the connecting portion 16. The side of the frame portion Nl to which the linking portion 13 is connected is adjacent to the side of the frame portion Nl to which the terminal portion 12 is connected, and is a side substantially perpendicular to the side.

[0076] The magnetic core portion 14 is arranged separately from the wire portion 11 inside the spiral formed by the wire portion 11. The magnetic core portion 14 is linked to the same side of the frame portion Nl to which the terminal portion 12 and the support portion 151 are connected, by the magnetic core connecting portion 17 extending from the inside of the product region Ml to the outside of the product region Ml. In other words, the magnetic core portion 14 is supported by the frame portion Nl via the magnetic core connecting portion 17 provided in the region of the first metal plate 10 in which the wire portion 11 is not arranged. The magnetic core portion 14 is a thick plate portion formed to the same thickness as the terminal portion 12 and the linking portion 13, and is formed in a substantially square shape in the substantially central portion of the product region Ml. The magnetic core connecting portion 17 is a thin plate portion formed to the same thickness as the wire portion 11 and the like. The magnetic core portion 14 is electrically independent from the wire portion 11. The magnetic core portion 14 is sometimes referred to as an inside thick plate portion.

[0077] The support portions 151 to 156 are arranged inside the product region Ml, and are arranged outside the spiral formed by the wire portion 11. One side of the support portions 151 to 156 extends to the outside of the product region Ml and is connected to the frame portion Nl. The support portions 151 to 156 are thick plate portions formed to the same thickness as the terminal portion 12 and the linking portion 13. The portion extending from the support portions 151 to 156 is a thin plate portion same as the connecting portion 16. The other side of the support portions 151 to 156 is not connected to the wire portion 11. In other words, the support portions 151 to 156 are electrically independent from the wire portion 11, and the support portions 151 to 156 are not conducted with the wire portion 11. The support portions 151 to 156 constitute portions for supporting thick plate portions of another metal plate.

[0078] The support portion 151 is connected to the same side of the frame portion Nl as the side to which the terminal portion 12 is connected, and is adjacent to the terminal portion 12 at a predetermined interval. The support portion 152 is connected to the same side of the frame portion Nl as the side to which the link portion 13 is connected, and is adjacent to the link portion 13 at a predetermined interval. The support portions 153 and 154 are connected to the opposite side of the frame portion Nl from the side to which the terminal portion 12 is connected, and are adjacent to each other at a predetermined interval. The support portions 155 and 156 are connected to the opposite side of the frame portion Nl from the side to which the link portion 13 is connected, and are adjacent to each other at a predetermined interval.

[0079] The upper surfaces (the surfaces on the second metal plate 20 side) of the wire portion 11, the connection portion 16, the magnetic core connection portion 17, and the frame portion Nl are located on substantially the same plane as the upper surfaces (the surfaces on the second metal plate 20 side) of the terminal portion 12, the link portion 13, the magnetic core portion 14, and the support portions 151 to 156. On the other hand, the lower surfaces of the wire portion 11, the connection portion 16, the magnetic core connection portion 17, and the frame portion Nl are located at positions recessed toward the second metal plate 20 side with respect to the lower surfaces of the terminal portion 12, the link portion 13, the magnetic core portion 14, and the support portions 151 to 156. Here, when the inductor is manufactured from the coil structure 1 and mounted on a substrate, the surface on the side opposite to the substrate is set as the lower surface, and the surface on the opposite side thereof is set as the upper surface (the same applies hereinafter).

[0080] Note that the frame portion Nl can include a first portion having the same thickness as the wire portion 11 and the like, and a second portion having the same thickness as the terminal portion 12 and the like. For example, as the second portion, in order to reinforce the frame portion Nl and prevent the metal plate from tilting, a reinforcing portion 18 can be provided at the four corners of the frame portion Nl. In this case, the lower surface of the reinforcing portion 18 is located on substantially the same plane as the lower surfaces of the terminal portion 12 and the like. The reinforcing portion 18 can be formed in an L shape, for example. In order to reinforce the frame portion Nl and prevent the metal plate from tilting, instead of the reinforcing portion 18, a second portion (thick plate portion) can be provided at portions other than the corners of the frame portion Nl, or the second portion (thick plate portion) can be further provided in addition to the reinforcing portion 18.

[0081] The thickness of the terminal portion 12, the link portion 13, the magnetic core portion 14, and the support portions 151 to 156 is approximately 50 μm to 500 μm, for example, and the thickness of the wire portion 11, the connection portion 16, the magnetic core connection portion 17, and the frame portion Nl is approximately half the thickness of the terminal portion 12 and the like, for example. Note that when the reinforcing portion 18 is provided on the frame portion Nl, the thickness of the reinforcing portion 18 is the same as the thickness of the terminal portion 12 and the like.

[0082] As Figure 6(b) As shown, the product region M2 of the second metal plate 20 has a conductor portion 21, a connection portion 231, a connection portion 232, a magnetic core portion 24, and support portions 251 to 256.

[0083] The conductor portion 21 is formed in a substantially rectangular spiral (substantially 3 / 4 turns) on the inner side of the product region M2, and is connected to the frame portion N2 by a plurality of connection portions 26 (six, for example, in this case) extending from the inner side of the product region M2 to the outer side of the product region M2. The number and connection positions of the connection portions 26 can be arbitrarily determined as long as the conductor portion 21 can be stably supported by the frame portion N2, but it is preferable to arrange them near the corners of the substantially rectangular conductor portion 21.

[0084] A connection end portion 231 is formed at a start point 211 that is one end of the conductor portion 21, and a connection end portion 232 is formed at an end point 212 that is the other end. The planar shapes of the connection end portions 231 and 232 are, for example, square or rectangular. The conductor portion 21, the connection portions 26, and the frame portion N2 are thin plate portions formed to a predetermined thickness, and the connection end portions 231 and 232 are thick plate portions formed to the same thickness as the conductor portion 21 and the like. The connection end portions 231 and 232 are sometimes collectively referred to as end thick plate portions.

[0085] The connection end portion 231 is arranged on the inner side of the product region M2, and extends to the outer side of the product region M2 from the opposite side of the connection portion of the start point 211 of the conductor portion 21 and is connected to the frame portion N2. The portion extending from the connection end portion 231 is a thin plate portion the same as the connection portions 26. The connection end portion 232 is arranged on the inner side of the product region M2, and extends to the outer side of the product region M2 from the opposite side of the connection portion of the end point 212 of the conductor portion 21 and is connected to the frame portion N2. The portion extending from the connection end portion 232 is a thin plate portion the same as the connection portions 26. The side of the frame portion N2 to which the connection end portion 231 is connected is adjacent to the side of the frame portion N2 to which the connection end portion 232 is connected, and the side thereof that is substantially perpendicular to the side.

[0086] The magnetic core portion 24 is arranged separately from the conductor portion 21 on the inner side of the spiral formed by the conductor portion 21. The magnetic core portion 24 is connected to the same side of the frame portion N2 as the side to which the connection end portion 231 and the support portion 251 are connected, by a magnetic core connection portion 27 extending from the inner side of the product region M2 to the outer side of the product region M2. In other words, the magnetic core portion 24 is supported by the frame portion N2 via the magnetic core connection portion 27 provided in the region of the second metal plate 20 in which the conductor portion 21 is not arranged. The magnetic core portion 24 is a thick plate portion formed to the same thickness as the connection end portions 231 and 232, and is formed in a substantially square shape in the substantially central portion of the product region M2. The magnetic core connection portion 27 is a thin plate portion formed to the same thickness as the conductor portion 21 and the like. The magnetic core portion 24 is electrically independent from the conductor portion 21. The magnetic core portion 24 is sometimes referred to as an inner thick plate portion.

[0087] The support portions 251 to 256 are arranged inside the product area M2 and outside the spiral formed by the conductor portion 21. One side of the support portions 251 to 256 extends to the outside of the product area M2 and is connected to the frame portion N2. The support portions 251 to 256 are thick plate portions formed to have the same thickness as the connecting portion 231 and the like. The portions extending from the support portions 251 to 256 are thin plate portions like the connecting portion 26. The other side of the support portions 251 to 256 is not connected to the conductor portion 21. In other words, the support portions 251 to 256 are electrically independent from the conductor portion 21, and conduction between the support portions 251 to 256 and the conductor portion 21 is not established. The support portions 251 to 256 constitute portions for supporting the thick plate portions of another metal plate.

[0088] The support portion 251 is connected to the same side of the frame portion N2 as the side to which the connecting portion 231 is connected, and is adjacent to the connecting portion 231 at a predetermined interval. The support portion 252 is connected to the same side of the frame portion N2 as the side to which the connecting portion 232 is connected, and is adjacent to the connecting portion 232 at a predetermined interval. The support portions 253 and 254 are connected to the opposite sides of the frame portion N2 from the sides to which the connecting portions 231 are connected, and are adjacent to each other at a predetermined interval. The support portions 255 and 256 are connected to the opposite sides of the frame portion N2 from the sides to which the connecting portions 232 are connected, and are adjacent to each other at a predetermined interval.

[0089] The upper surfaces (the surfaces on the third metal plate 30 side) of the conductor portion 21, the connecting portion 26, the magnetic core connecting portion 27, and the frame portion N2 are located on substantially the same plane as the upper surfaces (the surfaces on the third metal plate 30 side) of the connecting portions 231 and 232, the magnetic core portion 24, and the support portions 251 to 256. On the other hand, the lower surfaces of the conductor portion 21, the connecting portion 26, the magnetic core connecting portion 27, and the frame portion N2 are located at positions recessed toward the third metal plate 30 side with respect to the lower surfaces of the connecting portions 231 and 232, the magnetic core portion 24, and the support portions 251 to 256.

[0090] Note that the frame portion N2 can include a first portion having the same thickness as the conductor portion 21 and the like, and a second portion having the same thickness as the connecting portions 231 and 232 and the like. For example, as the second portion, in order to strengthen the joint between adjacent metal plates and prevent tilting of the metal plates, reinforcing portions 28 can be provided at the four corners of the frame portion N2. In this case, the lower surfaces of the reinforcing portions 28 are located on substantially the same plane as the lower surfaces of the connecting portions 231 and 232 and the like. The reinforcing portions 28 can be formed, for example, in an L shape. In order to strengthen the joint between adjacent metal plates and prevent tilting of the metal plates, instead of the reinforcing portions 28, a second portion (a thick plate portion) can be provided at portions other than the corners of the frame portion N2, or the second portion (a thick plate portion) can be further provided in addition to the reinforcing portions 28.

[0091] The thicknesses of connecting portions 231, 232, magnetic core portion 24, and support portions 251-256 are, for example, the same as the thickness of terminal portion 12 of the first metal plate 10, and the thicknesses of wire portion 21, connecting portion 26, magnetic core connecting portion 27, and frame portion N2 are, for example, the same as the thickness of wire portion 11 of the first metal plate 10. It should be noted that when a reinforcing portion 28 is provided on the frame portion N2, the thickness of the reinforcing portion 28 is the same as the thickness of connecting portions 231, etc.

[0092] like Figure 3 As shown in (a), the product area M3 of the third metal plate 30 has a wire portion 31, a connecting portion 331, a connecting portion 332, a magnetic core portion 34, and support portions 351 to 356.

[0093] The conductor portion 31 is formed in a generally rectangular spiral shape (approximately 3 / 4 turn) inside the product area M3, and is connected to the frame portion N3 by a plurality of connecting portions 36 (here, for example, 6) extending from the inside to the outside of the product area M3. The number and connection position of the connecting portions 36 can be arbitrarily determined as long as the conductor portion 31 can be stably supported by the frame portion N3, but it is preferable to arrange them near the corners of the generally rectangular conductor portion 31.

[0094] A connecting end portion 331 is formed at the starting point 311, which is one end of the conductor portion 31, and a connecting portion 332 is formed at the ending point 312, which is the other end. The planar shapes of the connecting portions 331 and 332 are, for example, square or rectangular. The conductor portion 31, the connecting portion 36, and the frame portion N3 are thin plate portions formed with a predetermined thickness, while the connecting portions 331 and 332 are thick plate portions formed with the same thickness as the conductor portion 31 and other components. Sometimes, the connecting portions 331 and 332 are collectively referred to as end thick plate portions.

[0095] Connecting portion 331 is arranged inside the product area M3 and extends to the outside of the product area M3 and connects to the frame portion N3 on the opposite side of the connection portion to the starting point 311 of the guide wire portion 31. The portion extending from connecting portion 331 is a thin plate portion, the same as connecting portion 36. Connecting portion 332 is arranged inside the product area M3 and extends to the outside of the product area M3 and connects to the frame portion N3 on the opposite side of the connection portion to the ending point 312 of the guide wire portion 31. The portion extending from connecting portion 332 is a thin plate portion, the same as connecting portion 36. The side of frame portion N3 connected to connecting portion 331 is adjacent to the side of frame portion N3 connected to connecting portion 332 and is substantially perpendicular to that side.

[0096] The magnetic core portion 34 is arranged separately from the wire portion 31 on the inner side of the spiral formed by the wire portion 31. The magnetic core portion 34 is joined to the same edge of the frame portion N3 as the edge to which the joining portion 331 and the support portion 351 are connected, by a magnetic core connecting portion 37 extending from the inner side of the product region M3 to the outer side of the product region M3. In other words, the magnetic core portion 34 is supported by the frame portion N3 via the magnetic core connecting portion 37 provided in the region of the third metal plate 30 in which the wire portion 31 is not arranged. The magnetic core portion 34 is a thick plate portion formed to the same thickness as the joining portions 331 and 332, and is formed in a substantially square shape in the substantially central portion of the product region M3. The magnetic core connecting portion 37 is a thin plate portion formed to the same thickness as the wire portion 31 and the like. The magnetic core portion 34 is electrically independent from the wire portion 31. The magnetic core portion 34 is sometimes referred to as an inner thick plate portion.

[0097] The support portions 351 to 356 are arranged on the inner side of the product region M3, and on the outer side of the spiral formed by the wire portion 31. One side of the support portions 351 to 356 extends to the outer side of the product region M3 and is connected to the frame portion N3. The support portions 351 to 356 are thick plate portions formed to the same thickness as the joining portion 331 and the like. The portions extending from the support portions 351 to 356 are thin plate portions the same as the connecting portion 36. The other side of the support portions 351 to 356 is not connected to the wire portion 31. In other words, the support portions 351 to 356 are electrically independent from the wire portion 31, and conduction between the support portions 351 to 356 and the wire portion 31 is not established. The support portions 351 to 356 constitute portions for supporting thick plate portions of another metal plate.

[0098] The support portion 351 is connected to the same edge of the frame portion N3 as the edge to which the joining portion 331 is connected, and is adjacent to the joining portion 331 at a predetermined interval. The support portion 352 is connected to the same edge of the frame portion N3 as the edge to which the joining portion 332 is connected, and is adjacent to the joining portion 332 at a predetermined interval. The support portions 353 and 354 are connected to the edges of the frame portion N3 opposite the edges to which the joining portion 331 is connected, and are adjacent to each other at a predetermined interval. The support portions 355 and 356 are connected to the edges of the frame portion N3 opposite the edges to which the joining portion 332 is connected, and are adjacent to each other at a predetermined interval.

[0099] The upper surfaces (the surfaces on the fourth metal plate 40 side) of the wire portion 31, the connecting portion 36, the magnetic core connecting portion 37, and the frame portion N3 are located on substantially the same plane as the upper surfaces (the surfaces on the fourth metal plate 40 side) of the joining portion 331, the joining portion 332, the magnetic core portion 34, and the support portions 351 to 356. On the other hand, the lower surfaces of the wire portion 31, the connecting portion 36, the magnetic core connecting portion 37, and the frame portion N3 are located at positions recessed toward the fourth metal plate 40 side with respect to the lower surfaces of the joining portion 331, the joining portion 332, the magnetic core portion 34, and the support portions 351 to 356.

[0100] It should be noted that the frame portion N3 may include a first portion with the same thickness as the wire portion 31, and a second portion with the same thickness as the connecting portions 331 and 332. For example, as the second portion, to strengthen the connection with adjacent metal plates and prevent the metal plates from tilting, reinforcing portions 38 may be provided at the four corners of the frame portion N3. In this case, the lower surface of the reinforcing portion 38 is located on approximately the same plane as the lower surfaces of the connecting portions 331 and 332. The reinforcing portion 38 may, for example, be formed in an L-shape. To strengthen the connection with adjacent metal plates and prevent the metal plates from tilting, a second portion (thick plate portion) may be provided in place of the reinforcing portion 38 in the portion of the frame portion N3 other than the corners, or the second portion (thick plate portion) may be provided in addition to the reinforcing portion 38.

[0101] The thicknesses of the connecting portions 331, 332, the magnetic core portion 34, and the support portions 351-356 are, for example, the same as the thickness of the terminal portion 12 of the first metal plate 10. The thicknesses of the wire portion 31, the connecting portion 36, the magnetic core connecting portion 37, and the frame portion N3 are, for example, the same as the thickness of the wire portion 11 of the first metal plate 10. It should be noted that when a reinforcing portion 38 is provided on the frame portion N3, the thickness of the reinforcing portion 38 is the same as the thickness of the connecting portions 331, etc.

[0102] like Figure 6 As shown in (b), the product area M4 of the fourth metal plate 40 has a wire portion 41, a connecting portion 431, a connecting portion 432, a magnetic core portion 44, and support portions 451 to 456.

[0103] The conductor portion 41 is formed in a generally rectangular spiral shape (approximately 3 / 4 turn) inside the product area M4, and is connected to the frame portion N4 by a plurality of connecting portions 46 (here, for example, 6) extending from the inside to the outside of the product area M4. The number and connection position of the connecting portions 46 can be arbitrarily determined as long as the conductor portion 41 can be stably supported by the frame portion N4, but it is preferable to arrange them near the corners of the generally rectangular conductor portion 41.

[0104] A connecting end portion 431 is formed at the starting point 411, which is one end of the conductor portion 41, and a connecting portion 432 is formed at the ending point 412, which is the other end. The planar shapes of the connecting portions 431 and 432 are, for example, square or rectangular. The conductor portion 41, the connecting portion 46, and the frame portion N4 are thin plate portions formed with a predetermined thickness, while the connecting portions 431 and 432 are thick plate portions formed with the same thickness as the conductor portion 41 and other components. Sometimes, the connecting portions 431 and 432 are collectively referred to as end thick plate portions.

[0105] The link portion 431 is arranged on the inner side of the product area M4 and extends to the outer side of the product area M4 opposite the connecting portion of the start point 411 of the wire portion 41 and is connected to the frame portion N4. The portion extending from the link portion 431 is a thin plate portion like the connecting portion 46. The link portion 432 is arranged on the inner side of the product area M4 and extends to the outer side of the product area M4 opposite the connecting portion of the end point 412 of the wire portion 41 and is connected to the frame portion N4. The portion extending from the link portion 432 is a thin plate portion like the connecting portion 46. The edge of the frame portion N4 to which the link portion 431 is connected is adjacent to the edge of the frame portion N4 to which the link portion 432 is connected and is substantially perpendicular to the edge.

[0106] The magnetic core portion 44 is arranged separately from the wire portion 41 on the inner side of the spiral formed by the wire portion 41. The magnetic core portion 44 is connected to the same edge of the frame portion N4 as the edge to which the link portions 431 and 451 are connected by the magnetic core connecting portion 47 extending from the inner side of the product area M4 to the outer side of the product area M4. In other words, the magnetic core portion 44 is supported by the frame portion N4 via the magnetic core connecting portion 47 provided in the area of the fourth metal plate 40 in which the wire portion 41 is not arranged. The magnetic core portion 44 is a thick plate portion formed to the same thickness as the link portions 431 and 432 and is formed in a substantially square shape in the substantially central portion of the product area M4. The magnetic core connecting portion 47 is a thin plate portion formed to the same thickness as the wire portion 41 and the like. The magnetic core portion 44 is electrically independent from the wire portion 41. The magnetic core portion 44 is sometimes referred to as an inner side thick plate portion.

[0107] The support portions 451 to 456 are arranged on the inner side of the product area M4 and on the outer side of the spiral formed by the wire portion 41. One side of the support portions 451 to 456 extends to the outer side of the product area M4 and is connected to the frame portion N4. The support portions 451 to 456 are thick plate portions formed to the same thickness as the link portion 431 and the like. The portion extending from the support portions 451 to 456 is a thin plate portion like the connecting portion 46. The other side of the support portions 451 to 456 is not connected to the wire portion 41. In other words, the support portions 451 to 456 are electrically independent from the wire portion 41 and conduction between the support portions 451 to 456 and the wire portion 41 is not conducted. The support portions 451 to 456 constitute portions for supporting thick plate portions of another metal plate.

[0108] Support portion 451 is connected to the side of frame portion N4 that is the same as the side connected to connecting portion 431, and is adjacent to connecting portion 431 at a predetermined interval. Support portion 452 is connected to the side of frame portion N4 that is the same as the side connected to connecting portion 432, and is adjacent to connecting portion 432 at a predetermined interval. Support portions 453 and 454 are connected to the sides of frame portion N4 opposite to the side connected to connecting portion 431, and are adjacent to each other at a predetermined interval. Support portions 455 and 456 are connected to the sides of frame portion N4 opposite to the side connected to connecting portion 432, and are adjacent to each other at a predetermined interval.

[0109] The upper surfaces (surfaces on the fifth metal plate 50 side) of the conductor portion 41, the connecting portion 46, the magnetic core connecting portion 47, and the frame portion N4 are located on approximately the same plane as the upper surfaces (surfaces on the fifth metal plate 50 side) of the connecting portion 431, the connecting portion 432, the magnetic core portion 44, and the support portions 451-456. On the other hand, the lower surfaces of the conductor portion 41, the connecting portion 46, the magnetic core connecting portion 47, and the frame portion N4 are located in a recessed position relative to the lower surfaces of the connecting portion 431, the connecting portion 432, the magnetic core portion 44, and the support portions 451-456 towards the fifth metal plate 50 side.

[0110] It should be noted that the frame portion N4 may include a first portion with the same thickness as the wire portion 41, and a second portion with the same thickness as the connecting portions 431 and 432. For example, as the second portion, to strengthen the connection with adjacent metal plates and prevent the metal plates from tilting, reinforcing portions 48 may be provided at the four corners of the frame portion N4. In this case, the lower surface of the reinforcing portion 48 is located on approximately the same plane as the lower surfaces of the connecting portions 431 and 432. The reinforcing portion 48 may be formed in an L-shape, for example. To strengthen the connection with adjacent metal plates and prevent the metal plates from tilting, a second portion (thick plate portion) may be provided in place of the reinforcing portion 48 in the portion of the frame portion N4 other than the corners, or the second portion (thick plate portion) may be provided in addition to the reinforcing portion 48.

[0111] The thicknesses of the connecting portions 431, 432, the magnetic core portion 44, and the support portions 451-456 are, for example, the same as the thickness of the terminal portion 12 of the first metal plate 10. The thicknesses of the wire portion 41, the connecting portion 46, the magnetic core connecting portion 47, and the frame portion N4 are, for example, the same as the thickness of the wire portion 11 of the first metal plate 10. It should be noted that when a reinforcing portion 48 is provided on the frame portion N4, the thickness of the reinforcing portion 48 is the same as the thickness of the connecting portions 431, etc.

[0112] like Figure 3 As shown in (a), the product area M5 of the fifth metal plate 50 has a wire portion 51, a connecting portion 531, a connecting portion 532, a magnetic core portion 54, and support portions 551 to 556.

[0113] The wire portion 51 is formed in a substantially rectangular spiral (substantially 3 / 4 turns) on the inner side of the product area M5, and is connected to the frame portion N5 by a plurality of connection portions 56 (six, for example, in this case) extending from the inner side of the product area M5 to the outer side of the product area M5. The number and connection positions of the connection portions 56 can be arbitrarily determined as long as the wire portion 51 can be stably supported by the frame portion N5, but it is preferable to arrange them near the corners of the substantially rectangular wire portion 51.

[0114] A joint end portion 531 is formed at the start point 511 which is one end of the wire portion 51, and a joint portion 532 is formed at the end point 512 which is the other end. The planar shape of the joint portions 531 and 532 is, for example, a square or a rectangular shape. The wire portion 51, the connection portions 56, and the frame portion N5 are thin plate portions formed in a predetermined thickness, and the joint portions 531 and 532 are thick plate portions formed in the same thickness as the wire portion 51 and the like. The joint portions 531 and 532 are sometimes collectively referred to as end thick plate portions.

[0115] The joint portion 531 is arranged on the inner side of the product area M5, and extends to the outer side of the product area M5 and is connected to the frame portion N5 on the opposite side from the connection portion of the start point 511 of the wire portion 51. The portion extending from the joint portion 531 is a thin plate portion like the connection portions 56. The joint portion 532 is arranged on the inner side of the product area M5, and extends to the outer side of the product area M5 and is connected to the frame portion N5 on the opposite side from the connection portion of the end point 512 of the wire portion 51. The portion extending from the joint portion 532 is a thin plate portion like the connection portions 56. The edge of the frame portion N5 to which the joint portion 531 is connected is adjacent to the edge of the frame portion N5 to which the joint portion 532 is connected, and the edge is substantially perpendicular with respect to the edge.

[0116] The magnetic core portion 54 is arranged separately from the wire portion 21 on the inner side of the spiral formed by the wire portion 51. The magnetic core portion 54 is joined to the same edge of the frame portion N5 as the edge to which the joint portion 531 and the support portion 551 are connected, by a magnetic core connection portion 57 extending from the inner side of the product area M5 to the outer side of the product area M5. In other words, the magnetic core portion 54 is supported by the frame portion N5 via the magnetic core connection portion 57 provided in the region of the fifth metal plate 50 in which the wire portion 51 is not arranged. The magnetic core portion 54 is a thick plate portion formed in the same thickness as the joint portions 531 and 532, and is formed in a substantially square shape in the substantially central portion of the product area M5. The magnetic core connection portion 57 is a thin plate portion formed in the same thickness as the wire portion 51 and the like. The magnetic core portion 54 is electrically independent from the wire portion 51. The magnetic core portion 54 is sometimes referred to as an inner side thick plate portion.

[0117] The support portions 551 to 556 are arranged inside the product region M5 and outside the spiral formed by the wire portion 51. One side of the support portions 551 to 556 extends to the outside of the product region M5 and is connected to the frame portion N5. The support portions 551 to 556 are thick plate portions formed to have the same thickness as the linking portion 531 and the like. The portions extending from the support portions 551 to 556 are thin plate portions like the connecting portion 56. The other side of the support portions 551 to 556 is not connected to the wire portion 51. In other words, the support portions 551 to 556 are electrically independent from the wire portion 51, and conduction between the support portions 551 to 556 and the wire portion 51 is not established. The support portions 551 to 556 constitute portions for supporting the thick plate portions of another metal plate.

[0118] The support portion 551 is connected to the same side of the frame portion N5 as the side to which the linking portion 531 is connected, and is adjacent to the linking portion 531 at a predetermined interval. The support portion 552 is connected to the same side of the frame portion N5 as the side to which the linking portion 532 is connected, and is adjacent to the linking portion 532 at a predetermined interval. The support portions 553 and 554 are connected to the opposite sides of the frame portion N5 from the sides to which the linking portions 531 are connected, and are adjacent to each other at a predetermined interval. The support portions 555 and 556 are connected to the opposite sides of the frame portion N5 from the sides to which the linking portions 532 are connected, and are adjacent to each other at a predetermined interval.

[0119] The upper surfaces (the surfaces on the sixth metal plate 60 side) of the wire portion 51, the connecting portion 56, the magnetic core connecting portion 57, and the frame portion N5 are located on substantially the same plane as the upper surfaces (the surfaces on the sixth metal plate 60 side) of the linking portions 531 and 532, the magnetic core portion 54, and the support portions 551 to 556. On the other hand, the lower surfaces of the wire portion 51, the connecting portion 56, the magnetic core connecting portion 57, and the frame portion N5 are located at positions recessed toward the sixth metal plate 60 side with respect to the lower surfaces of the linking portions 531 and 532, the magnetic core portion 54, and the support portions 551 to 556.

[0120] Note that the frame portion N5 can include a first portion having the same thickness as the wire portion 51 and the like, and a second portion having the same thickness as the linking portions 531 and 532 and the like. For example, as the second portion, in order to strengthen the joint with an adjacent metal plate and prevent tilting of the metal plate, a reinforcing portion 58 can be provided at the four corners of the frame portion N5. In this case, the lower surface of the reinforcing portion 58 is located on substantially the same plane as the lower surfaces of the linking portions 531 and 532 and the like. The reinforcing portion 58 can be formed in an L shape, for example. In order to strengthen the joint with an adjacent metal plate and prevent tilting of the metal plate, instead of the reinforcing portion 58, a second portion (a thick plate portion) can be provided at portions other than the corners of the frame portion N5, or the second portion (a thick plate portion) can be further provided in addition to the reinforcing portion 58.

[0121] The thickness of the linking portions 531, 532, the core portion 54, and the support portions 551 to 556 is, for example, the same as the thickness of the terminal portion 12 of the first metal plate 10, and the thickness of the lead portion 51, the connecting portion 56, the core connecting portion 57, and the frame portion N5 is, for example, the same as the thickness of the lead portion 11 of the first metal plate 10. Note that when the reinforcing portion 58 is provided on the frame portion N5, the thickness of the reinforcing portion 58 is the same as the thickness of the linking portion 531 and the like.

[0122] As shown in (b), the product region M6 of the sixth metal plate 60 has a lead portion 61, a terminal portion 62, a linking portion 63, a core portion 64, and support portions 651 to 656. Figure 6

[0123] The lead portion 61 is formed in a substantially rectangular spiral (substantially 3 / 4 turns) on the inner side of the product region M6, and is connected to the frame portion N6 by a plurality of connecting portions 66 (six, for example, in this case) extending from the inner side of the product region M6 to the outer side of the product region M6. The number and the connecting positions of the connecting portions 66 can be arbitrarily determined as long as the lead portion 61 can be stably supported by the frame portion N6, but it is preferable to arrange them near the corners of the substantially rectangular lead portion 61.

[0124] The linking portion 63 is formed at a start point 611 which is one end of the lead portion 61, and the terminal portion 62 is formed at an end point 612 which is the other end. The planar shape of the terminal portion 62 and the linking portion 63 is, for example, a square or a rectangle. The lead portion 61, the connecting portions 66, and the frame portion N6 are thin plate portions formed to a predetermined thickness, and the terminal portion 62 and the linking portion 63 are thick plate portions formed to the same thickness as the components such as the lead portion 61. The terminal portion 62 and the linking portion 63 are sometimes collectively referred to as end thick plate portions.

[0125] The linking portion 63 is arranged on the inner side of the product region M6, and extends to the outer side of the product region M6 and is connected to the frame portion N6 on the opposite side from the connecting portion of the start point 611 of the lead portion 61. The portion extending from the linking portion 63 is a thin plate portion the same as the connecting portions 66. The terminal portion 62 is arranged on the inner side of the product region M6, and extends to the outer side of the product region M6 and is connected to the frame portion N6 on the opposite side from the connecting portion of the end point 612 of the lead portion 61. The portion extending from the terminal portion 62 is a thin plate portion the same as the connecting portions 66. The side of the frame portion N6 to which the terminal portion 62 is connected is adjacent to the side of the frame portion N6 to which the linking portion 63 is connected, and the side thereof which is substantially perpendicular to the side.

[0126] ​The magnetic core portion 64 is arranged separately from the wire portion 61 on the inner side of the spiral formed by the wire portion 61. The magnetic core portion 64 is joined to the same side of the frame portion N6 as the joining portion 63 and the support portion 656 are joined to, by a magnetic core connecting portion 67 extending from the inner side of the product region M6 to the outer side of the product region M6. In other words, the magnetic core portion 64 is supported by the frame portion N6 via the magnetic core connecting portion 67 provided in the region of the sixth metal plate 60 where the wire portion 61 is not arranged. The magnetic core portion 64 is a thick plate portion formed to the same thickness as the terminal portion 62 and the joining portion 63, and is formed in a substantially square shape in the substantially central portion of the product region M6. The magnetic core connecting portion 67 is a thin plate portion formed to the same thickness as the wire portion 61 and the like. The magnetic core portion 64 is electrically independent from the wire portion 61. The magnetic core portion 64 is sometimes referred to as an inner thick plate portion.

[0127] The support portions 651 to 656 are arranged on the inner side of the product region M6, and on the outer side of the spiral formed by the wire portion 61. One side of the support portions 651 to 656 extends to the outer side of the product region M6 and is connected to the frame portion N6. The support portions 651 to 656 are thick plate portions formed to the same thickness as the terminal portion 62 and the joining portion 63. The portions extending from the support portions 651 to 656 are thin plate portions the same as the connecting portion 66. The other side of the support portions 651 to 656 is not connected to the wire portion 61. In other words, the support portions 651 to 656 are electrically independent from the wire portion 61, and conduction between the support portions 651 to 656 and the wire portion 61 is not established. The support portions 651 to 656 constitute portions for supporting thick plate portions of another metal plate.

[0128] The support portion 651 is connected to the same side of the frame portion N6 as the terminal portion 62 is connected to, and is adjacent to the terminal portion 62 at a predetermined interval. The support portion 656 is connected to the same side of the frame portion N6 as the joining portion 63 is connected to, and is adjacent to the joining portion 63 at a predetermined interval. The support portions 654 and 655 are connected to the opposite sides of the frame portion N6 from the side to which the terminal portion 62 is connected, and are adjacent to each other at a predetermined interval. The support portions 652 and 653 are connected to the opposite sides of the frame portion N6 from the side to which the joining portion 63 is connected, and are adjacent to each other at a predetermined interval.

[0129] The upper surfaces (the surfaces opposite the fifth metal plate 50) of the wire portion 61, the connecting portion 66, the magnetic core connecting portion 67, and the frame portion N6 are located on substantially the same plane as the upper surfaces (the surfaces opposite the fifth metal plate 50) of the terminal portion 62, the joining portion 63, the magnetic core portion 64, and the support portions 651 to 656. On the other hand, the lower surfaces of the wire portion 61, the connecting portion 66, the magnetic core connecting portion 67, and the frame portion N6 are located at positions recessed toward the side opposite the fifth metal plate 50, relative to the lower surfaces of the terminal portion 62, the joining portion 63, the magnetic core portion 64, and the support portions 651 to 656.

[0130] Note that the frame portion N6 can include a first portion having the same thickness as the conductor portion 61 and the like, and a second portion having the same thickness as the terminal portion 62 and the like. For example, as the second portion, in order to make the joining with the adjacent metal plate firm and prevent the inclination of the metal plate, a reinforcing portion 68 can be provided at the four corners of the frame portion N6. In this case, the lower surface of the reinforcing portion 68 is located on substantially the same plane as the lower surface of the terminal portion 62 and the like. The reinforcing portion 68 can be formed in an L shape, for example. In order to make the joining with the adjacent metal plate firm and prevent the inclination of the metal plate, instead of the reinforcing portion 68, a second portion (thick plate portion) can be provided at portions other than the corners of the frame portion N6, or the second portion (thick plate portion) can be further provided in addition to the reinforcing portion 68.

[0131] The thickness of the terminal portion 62, the connecting portion 63, the magnetic core portion 64, and the support portions 651 to 656 is the same as the thickness of the terminal portion 12 and the like of the first metal plate 10, for example, and the thickness of the conductor portion 61, the connection portion 66, the magnetic core connection portion 67, and the frame portion N6 is the same as the thickness of the conductor portion 11 and the like of the first metal plate 10, for example. Note that when the reinforcing portion 68 is provided on the frame portion N6, the thickness of the reinforcing portion 68 is the same as the thickness of the connecting portion 63 and the like.

[0132] Figure 3 (a) is a sectional view of the coil structure 1 along Figure 4 line A-A of (a). Figure 4 (b) is a sectional view of the coil structure 1 along Figure 5 line B-B of (a). Figure 5 (a) is a sectional view of the coil structure 1 along Figure 7 line C-C of (a). Figure 3 (b) is a sectional view of the coil structure 1 along Figure 7 line D-D of (a). Figure 3 (a) is a sectional view of the coil structure 1 along Figure 8 line E-E of (a). Figure 3 (b) is a sectional view of the coil structure 1 along Figure 8 line F-F of (a). Figure 3 (a) is a sectional view of the coil structure 1 along Figure 9 line G-G of (a). Figure 3 (b) is a sectional view of the coil structure 1 along Figure 9 line H-H of (a). Figure 3 (a) is a sectional view of the coil structure 1 along Figure 10 line I-I of (a). Figure 3 (b) is a sectional view of the coil structure 1 along Figure 10 line J-J of (a).Figure 3 is a cross-sectional view of the line K-K of the coil structure 1 of Figure 11 (a). Note that in Figure 3 , the representation of a part of the symbols is omitted for convenience.

[0133] As shown in Figure 11 , and Figure 3 , in the coil structure 1, the adjacent metal plates are joined to each other. The adjacent metal plates can be joined to each other, for example, by diffusion joining. With regard to diffusion joining, since it can join the upper and lower metal plates without the aid of a material having different electrical conductivity or thermal conductivity such as solder, it is preferable from the viewpoint of being able to reduce voltage loss generated at the joint.

[0134] Specifically, the second metal plate 20 is stacked on the first metal plate 10, and the thick plate portions thereof are joined to each other. That is, the support portion 255 is joined on the terminal portion 12, the link portion 231 is stacked on the link portion 13, the support portion 256 is stacked on the support portion 151, the support portion 251 is stacked on the support portion 152, the link portion 232 is stacked on the support portion 153, the support portion 252 is stacked on the support portion 154, the support portion 253 is stacked on the support portion 155, and the support portion 254 is stacked on the support portion 156. In addition, the magnetic core portion 24 is joined on the magnetic core portion 14. Further, each of the reinforcing portions 28 is joined on each of the reinforcing portions 18.

[0135] Thus, the link portion 13 connected to the terminal 112 of the wire portion 11 and the link portion 231 connected to the terminal 211 of the wire portion 21 are conducted, and the wire portion 11 and the wire portion 21 are connected in series. In addition, since the wire portion 11 and the wire portion 21 are formed thinner than the terminal portion 12 or the link portion 231 and the like, the upper surface of the wire portion 11 does not contact the lower surface of the wire portion 21. In addition, since any one of the thick plate portions of the first metal plate 10 is necessarily disposed on the lower side of each of the thick plate portions of the second metal plate 20, the upper and lower metal plates can be easily joined to each other.

[0136] Similarly, the third metal plate 30 is stacked on the second metal plate 20, and the thick plate portions thereof are joined to each other. That is, the support portion 355 is joined on the link portion 231, the link portion 331 is stacked on the link portion 232, the support portion 356 is stacked on the support portion 251, the support portion 351 is stacked on the support portion 252, the support portion 352 is stacked on the support portion 253, the link portion 332 is stacked on the support portion 254, the support portion 353 is stacked on the support portion 255, and the support portion 354 is stacked on the support portion 256. In addition, the magnetic core portion 34 is joined on the magnetic core portion 24. Further, each of the reinforcing portions 38 is joined on each of the reinforcing portions 28.

[0137] Thus, the link portion 232 connected to the end point 212 of the conductor portion 21 and the link portion 331 connected to the start point 311 of the conductor portion 31 are in conduction, and the conductor portion 21 and the conductor portion 31 are connected in series. In addition, since the conductor portion 21 and the conductor portion 31 are formed thinner than the link portion 231 or the link portion 331 and the like, the upper surface of the conductor portion 21 does not come into contact with the lower surface of the conductor portion 31. In addition, since any one of the thick plate portions of the second metal plate 20 is necessarily arranged on the lower side of each thick plate portion of the third metal plate 30, the upper and lower metal plates can be easily joined to each other.

[0138] Likewise, the fourth metal plate 40 is stacked on the third metal plate 30, and the thick plate portions thereof are joined to each other. That is, the support portion 455 is joined on the link portion 331, the link portion 431 is stacked on the link portion 332, the support portion 456 is stacked on the support portion 351, the support portion 451 is stacked on the support portion 352, the support portion 452 is stacked on the support portion 353, the link portion 432 is stacked on the support portion 354, the support portion 453 is stacked on the support portion 355, and the support portion 454 is stacked on the support portion 356. In addition, the magnetic core portion 44 is joined on the magnetic core portion 34. In addition, each reinforcing portion 48 is joined on each reinforcing portion 38.

[0139] Thus, the link portion 332 connected to the end point 312 of the conductor portion 31 and the link portion 431 connected to the start point 411 of the conductor portion 41 are in conduction, and the conductor portion 31 and the conductor portion 41 are connected in series. In addition, since the conductor portion 31 and the conductor portion 41 are formed thinner than the link portion 331 or the link portion 431 and the like, the upper surface of the conductor portion 31 does not come into contact with the lower surface of the conductor portion 41. In addition, since any one of the thick plate portions of the third metal plate 30 is necessarily arranged on the lower side of each thick plate portion of the fourth metal plate 40, the upper and lower metal plates can be easily joined to each other.

[0140] Likewise, the fifth metal plate 50 is stacked on the fourth metal plate 40, and the thick plate portions thereof are joined to each other. That is, the support portion 556 is joined on the link portion 431, the link portion 531 is stacked on the link portion 432, the support portion 555 is stacked on the support portion 451, the support portion 551 is stacked on the support portion 452, the support portion 552 is stacked on the support portion 453, the link portion 532 is stacked on the support portion 454, the support portion 553 is stacked on the support portion 455, and the support portion 554 is stacked on the support portion 456. In addition, the magnetic core portion 54 is joined on the magnetic core portion 44. In addition, each reinforcing portion 58 is joined on each reinforcing portion 48.

[0141] Thus, the connection portion 432 connected to the terminal point 412 of the wire portion 41 and the connection portion 531 connected to the start point 511 of the wire portion 51 are conducted, and the wire portion 41 and the wire portion 51 are connected in series. In addition, since the wire portion 41 and the wire portion 51 are formed thinner than the connection portion 431 or the connection portion 531 and the like, the upper surface of the wire portion 41 does not contact the lower surface of the wire portion 51. In addition, since any one of the thick plate portions of the fourth metal plate 40 is necessarily arranged on the lower side of each of the thick plate portions of the fifth metal plate 50, the upper and lower metal plates can be easily joined to each other.

[0142] Similarly, the sixth metal plate 60 is stacked on the fifth metal plate 50, and the thick plate portions thereof are joined to each other. That is, the support portion 655 is joined on the connection portion 531, the connection portion 63 is stacked on the connection portion 532, the support portion 654 is stacked on the support portion 551, the support portion 656 is stacked on the support portion 552, the support portion 651 is stacked on the support portion 553, the terminal portion 62 is stacked on the support portion 554, the support portion 652 is stacked on the support portion 555, and the support portion 653 is stacked on the support portion 556. In addition, the magnetic core portion 64 is joined on the magnetic core portion 54. In addition, each of the reinforcing portions 68 is joined on each of the reinforcing portions 58.

[0143] Thus, the connection portion 532 connected to the terminal point 512 of the wire portion 51 and the connection portion 63 connected to the start point 611 of the wire portion 61 are conducted, and the wire portion 51 and the wire portion 61 are connected in series. In addition, since the wire portion 51 and the wire portion 61 are formed thinner than the terminal portion 62 or the connection portion 63 and the like, the upper surface of the wire portion 51 does not contact the lower surface of the wire portion 61. In addition, since any one of the thick plate portions of the fifth metal plate 50 is necessarily arranged on the lower side of each of the thick plate portions of the sixth metal plate 60, the upper and lower metal plates can be easily joined to each other.

[0144] With the above structure, in the coil structure 1, the terminal point 112 of the wire portion 11 and the start point 211 of the wire portion 21, the terminal point 212 of the wire portion 21 and the start point 311 of the wire portion 31, the terminal point 312 of the wire portion 31 and the start point 411 of the wire portion 41, the terminal point 412 of the wire portion 41 and the start point 511 of the wire portion 51, and the terminal point 512 of the wire portion 51 and the start point 611 of the wire portion 61 are sequentially connected. Thus, one spiral coil is formed from the start point 111 of the wire portion 11 to the terminal point 612 of the wire portion 61. In addition, in the coil structure 1, the magnetic core portions 14, 24, 34, 44, 54, and 64 are sequentially stacked, and thus the magnetic core C is formed inside the one spiral coil.

[0145] Figure 12 and Figure 3 are diagrams showing manufacturing steps of the coil structure according to the first embodiment. Note that,Figures 7-12 and Figures 1-6 is a sectional view corresponding to line B-B of Figures 7-12 (a) and shows only one product region.

[0146] First, in the process shown in Figure 13 (a), a plate-shaped metal 100 having a constant thickness and a planar shape as shown in Figure 14 (a) is prepared. The plate-shaped metal 100 is a component that eventually becomes the first metal plate 10 and is formed of, for example, copper, a copper alloy, a 42 alloy, an Fe-Ni alloy, or the like. The thickness of the plate-shaped metal 100 can be, for example, about 50 μm to 500 μm. A plurality of product regions are defined in the plate-shaped metal 100. Further, a resist layer 310 is formed on the entire upper surface of the plate-shaped metal 100, and a resist layer 320 is formed on the entire lower surface of the plate-shaped metal 100. The resist layers 310 and 320 can be formed by, for example, laminating a photosensitive dry film resist.

[0147] Next, in the process shown in Figure 13 (b), the resist layer 310 is subjected to exposure and development to form an opening portion 310x that selectively exposes the upper surface of the plate-shaped metal 100. In addition, the resist layer 320 is subjected to exposure and development to form an opening portion 320x that selectively exposes the lower surface of the plate-shaped metal 100.

[0148] Next, in the process shown in Figure 14 (c), the plate-shaped metal 100 exposed in the opening portion 310x is subjected to semi-etching from the upper surface side, and the plate-shaped metal 100 exposed in the opening portion 320x is subjected to semi-etching from the lower surface side. Thus, the plate-shaped metal 100 is patterned to form the first metal plate 10 having the lead portion 11, the terminal portion 12, and the like.

[0149] Note that, in the plate-shaped metal 100, a region in which the resist layers 310 and 320 overlap in a plan view maintains the original thickness since it is not etched, and this portion becomes a thick plate portion. In addition, a region in which neither of the resist layers 310 and 320 is formed in a plan view is semi-etched from both surfaces and is penetrated. In addition, a region in which only the resist layer 310 is formed in a plan view is semi-etched only from the lower surface side and becomes a thin plate portion having a thickness of about half the original thickness. In the case where the plate-shaped metal 100 is copper, ferric chloride solution can be used in the semi-etching, for example.

[0150] Next, in the process shown in Figure 3 (a), a plate-shaped metal 100 having a constant thickness and a planar shape as shown in Figure 13 (a) is prepared. The plate-shaped metal 100 is a component that eventually becomes the first metal plate 10 and is formed of, for example, copper, a copper alloy, a 42 alloy, an Fe-Ni alloy, or the like. The thickness of the plate-shaped metal 100 can be, for example, about 50 μm to 500 μm. A plurality of product regions are defined in the plate-shaped metal 100. Further, a resist layer 310 is formed on the entire upper surface of the plate-shaped metal 100, and a resist layer 320 is formed on the entire lower surface of the plate-shaped metal 100. The resist layers 310 and 320 can be formed by, for example, laminating a photosensitive dry film resist. Figure 3(c) The same method is used to produce 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. The planar shape of each metal plate is as shown in Figure 13 (b) The cross-sectional shape of each metal plate is as shown in Figure 13 (b). Figure 14

[0151] Next, in the process shown in Figure 13 (b), the respective metal plates are stacked and the thick plate portions of the adjacent metal plates are joined to each other. Specifically, the respective metal plates are stacked in the order shown in Figure 13 (b) to form a stack, and the stack is subjected to pressurization and heating in the up-down direction under a vacuum atmosphere to perform diffusion joining. Thus, the thick plate portions of the adjacent metal plates are directly joined to each other, thereby completing the coil structure 1. At the time of performing diffusion joining, since any one of the thick plate portions of the lower layer is necessarily arranged on the lower side of each thick plate portion except for the lowermost layer, the joining of the thick plate portions can be performed collectively. Note that it is preferable to make the materials of the respective metal plates the same, so that the adjacent metals can be well joined to each other by diffusion joining.

[0152] Although the coil structure 1 is completed by the above process, the inductor 2 can be produced by continuing the process of Figure 3 .

[0153] In the process shown in Figure 5 (a), the encapsulation resin 150 is formed in the coil structure 1 shown in Figures 6-12 (b). As the insulating resin constituting the encapsulation resin 150, a thermosetting resin or a thermoplastic resin such as an epoxy-based resin, a polyimide-based resin, a phenol-based resin, an acrylic-based resin, or the like can be used. Note that, regarding the formation of the encapsulation resin 150, it is performed in such a manner that a part of the end plate portion on the one end side of the series-connected lead portion of the coil structure 1 and a part of the end plate portion on the other end side of the series-connected lead portion are exposed.

[0154] That is, the encapsulation resin 150 is formed in such a manner that the lower surface of the one end of the series-connected lead portion of the coil structure 1, that is, the terminal portion 12 is exposed. In addition, the encapsulation resin 150 is formed in such a manner that the lower surface of the support portion 154 stacked on the other end of the series-connected lead portion of the coil structure 1, that is, the terminal portion 62 is exposed.

[0155] After the encapsulation resin 150 is formed, it is preferable to polish or blast the lower surface of the encapsulation resin 150 to remove the resin burrs on the lower surfaces of the terminal portion 12 or the support portion 154, or the like. In order to form the encapsulation resin 150, a low-pressure molding method such as transfer molding or compression molding can be used, for example.​

[0156] Next, in the process shown in Figure 14 (b), the structure shown in Figure 14 (a) is cut at the positions of the cutting lines L using a cutting blade or the like to singulate it, thereby manufacturing the inductor 2. The structure shown in Figure 15 (a) can be singulated by pressing or etching. Note that the cutting lines L are positions corresponding to the broken lines showing the product regions M of Figure 15 (b). By cutting, the side surfaces of the terminal portions 12, the support portions 255, 353, 452, 551, and 654, and the like are exposed from one side surface of the packaging resin 150. In addition, the side surfaces of the support portions 154, 252, 351, 456, 554, and the terminal portions 62, and the like are exposed from the other side surface of the packaging resin 150. The inductors 2 are manufactured from each of the product regions M. Figure 14 (a) and Figure 15 (b). The planar shape of the inductor 2 is, for example, a rectangular shape such as a square or a rectangle.

[0157] The side surface and the lower surface of the terminal portion 12, the side surface of the support portion 255, the side surface of the support portion 353, the side surface of the support portion 452, the side surface of the support portion 551, and the side surface of the support portion 654, which are exposed from the packaging resin 150, become external connection terminals 1A. In addition, the side surface and the lower surface of the support portion 154, the side surface of the support portion 252, the side surface of the support portion 351, the side surface of the support portion 456, the side surface of the support portion 554, and the side surface of the terminal portion 62, which are exposed from the packaging resin 150, become external connection terminals 1B.

[0158] Note that Figure 15 (b) is a view of Figure 15 (a) viewed from the lower surface side. In other words, Figure 1 (b) is a view obtained by turning over upside down Figure 16 (a) by 180 degrees in the paper front-rear direction. The planar shape of the inductor 2 can be, for example, approximately 3 mm x 3 mm of a substantially rectangular shape. The thickness of the inductor 2 can be, for example, approximately 1.0 mm.

[0159] Figure 16 is a cross-sectional view for explaining a mounting method of the inductor according to the first embodiment, Figure 16 (a) shows an H cross section of Figure 16 (b) shows an I cross section of Figure 16 (b) in an upside-down manner. In Figure 16 (a) and Figure 17 (a) and Figure 17In (b), the inductor 2 is mounted on the substrate 200. Specifically, a pad 210 is formed on one surface of the substrate 200, and a part of the upper surface of the pad 210 is exposed within an opening portion 220x of a solder resist layer 220. The upper surface of the pad 210 exposed within the opening portion 220x is electrically connected to the external connection terminals IA and IB of the inductor 2 by solder 230.

[0160] In this way, in the coil structure 1, the respective metal plates are laminated, and the magnetic core portions (inner thick plate portions) of the adjacent metal plates are joined to each other to form the magnetic core C. By arranging the magnetic core C inside one spiral coil, it is possible to increase the magnetic flux, and it is possible to increase the induced electromotive force. That is, by packaging the coil structure 1 with the packaging resin 150 in a manner that the external connection terminals IA and IB are exposed, it is possible to realize a small inductor 2 that can obtain a large induced electromotive force.

[0161] In addition, in the coil structure 1, the magnetic core connecting portions are provided in regions of the respective metal plates in which the wire portions are not arranged, to support the magnetic core portions arranged inside the wire portions. By providing this structure, it is possible to provide both the wire portions and the magnetic core portions on one metal plate, and thus, by laminating the respective metal plates, it is possible to easily arrange the magnetic core C inside one spiral coil, the magnetic core C being formed by laminating the magnetic core portions of the respective metal plates.

[0162] In addition, in the coil structure 1, the respective metal plates include: a spiral wire portion; end thick plate portions formed at both ends of the wire portion to be thicker than the wire portion; and inner thick plate portions formed to have the same thickness as the end thick plate portions, and arranged inside the spiral formed by the wire portion so as to be separated from the wire portion. Further, the respective metal plates are laminated, one of the end thick plate portions of the adjacent metal plates are joined to each other, to form one spiral coil in which the wire portions of the respective metal plates are connected in series. In this structure, by increasing the number of laminated metal plates, it is possible to easily increase the number of turns of the coil. Thus, it is possible to further increase the induced electromotive force of the inductor 2 using the coil structure 1.

[0163] In addition, in the coil structure 1, at the lower side of each thick plate portion of one metal plate, any one of the thick plate portions of another metal plate located at the lower layer is arranged. In other words, the support portion of one of the adjacent metal plates is joined to the end thick plate portion or the support portion of the other of the adjacent metal plates. Thus, it is possible to easily join the upper and lower metal plates to each other.

[0164] For example, when it is assumed that a portion of the thick plate portion of another metal plate that is not arranged in the lower layer exists on the lower side of each thick plate portion of one metal plate, since the thick plate portion that is not supported and is in a state of being in the air is generated in a case where heat and pressure are applied from above and below to join each metal plate, it is difficult to perform joining at the portion. In contrast, in the coil structure 1, as described above, any one of the thick plate portions of another metal plate that is arranged in the lower layer exists on the lower side of each thick plate portion of one metal plate. Therefore, each metal plate can be easily joined by diffusion joining or the like.

[0165] In addition, in the coil structure 1, the end thick plate portion on the one end side of the series-connected wire portion and the support portion of another metal plate laminated with the end thick plate portion on the one end side constitute one external connection terminal. In addition, the end thick plate portion on the other end side of the series-connected wire portion and the support portion of another metal plate laminated with the end thick plate portion on the other end side constitute another external connection terminal. Specifically, the five support portions laminated on the upper side of the terminal portion of the metal plate that is the lowermost layer constitute the external connection terminal 1A, and the five support portions laminated on the lower side of the terminal portion of the metal plate that is the uppermost layer constitute the external connection terminal 1B.

[0166] That is, the support portions 255, 353, 452, 551, and 654 are laminated in order from the lower to the upper side of the terminal portion 12, thereby constituting the external connection terminal 1A. In addition, on the lower side of the terminal portion 62, the support portions 554, 456, 351, 252, and 154 are laminated in order from the upper to the lower side, thereby constituting the external connection terminal 1B. Since each thick plate portion that constitutes the external connection terminal 1A is in conduction with each other, connection with the outside can be performed at any layer of the external connection terminal 1A. Similarly, since each thick plate portion that constitutes the external connection terminal 1B is in conduction with each other, connection with the outside can be performed at any layer of the external connection terminal 1B.

[0167] In the above description, for convenience, the wire portion 11 side is taken as the starting point and the wire portion 61 side is taken as the end point, but the coil structure 1 is non-polar, and the current can 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.

[0168] Note that the coil structure 1 can be shipped as a product, and the inductor 2 can be shipped as a product. In addition, any one or more 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 can be shipped as a lead frame. That is, a lead frame can be shipped, the lead frame including: a spiral lead wire portion; end portion thick plate portions formed at both ends of the lead wire portion to be thicker than the lead wire portion; and an inner side thick plate portion formed to have the same thickness as the end portion thick plate portions and arranged on the inner side of the spiral formed by the lead wire portion to be separated from the lead wire portion, the inner side thick plate portion constituting a magnetic core.

[0169] <Modification 1 of the 1st embodiment>

[0170] In Modification 1 of the 1st embodiment, an example in which the lead wire portion, the end portion thick plate portion, and the inner side thick plate portion to be the magnetic core portion of each metal plate are formed in the same pattern is shown. Note that in Modification 3 of the 1st embodiment, the description of the same constituent portions as those of the above-described embodiment can be omitted.

[0171] Figure 16 is a plan view showing a coil structure according to Modification 1 of the 1st embodiment, Figure 17 (a) is an overall view, Figure 16 (b) is Figure 17 is an enlarged view of the vicinity of one product region M of (a).

[0172] Figure 17 The coil structure 3 shown is a structure in which two metal plates are laminated, and the upper and lower adjacent metal plates are joined to each other. In the present embodiment, a coil structure 3 of a three-layer structure in which a first metal plate 70, a second metal plate 80, and a third metal plate 90 are sequentially laminated is shown, but the coil structure 3 shown can also be a two-layer structure.

[0173] In a plan view, the coil structure 3 has a plurality of product regions M arranged in a vertical and horizontal direction. Each product region M is a region that constitutes an inductor after resin packaging of the entire coil structure 3 and singulation. Around each product region M, a frame portion N in a frame shape that supports each product region M from the periphery side is formed, and adjacent frame portions N are integrally formed with each other to be connected to each other. In the present embodiment, the lengths of each side of the frame portion N are equal. Note that in the present embodiment, the frame portion N is formed in a frame shape, but the shape of the frame portion N is not limited to this. For example, the frame portion N can be formed in a rectangular frame shape, a circular frame shape, or a polygonal frame shape. Figure 18 (a) has 18 (3 rows x 6 columns) product regions M arranged as one example, but is not limited thereto.

[0174] Figure 18 and Figure 18 are plan views showing the vicinity of the product region of each metal plate before lamination. Specifically,Figure 18 (a) is a plan view of the first metal plate 70. Figure 18 (b) is a plan view of the second metal plate 80. Figure 18 is a plan view of the third metal plate 90.

[0175] Note that the first metal plate 70, the second metal plate 80, and the third metal plate 90 are each a planar shape identical to Figure 19 (a), Figure 20 (a) ~ Figure 19 shows a portion (a vicinity of one product region) of each metal plate corresponding to Figure 19 (b). In addition, in Figure 20 (a) ~ Figure 18 , a gray portion indicates a thin plate portion, and a satin pattern portion indicates a thick plate portion formed thicker than the thin plate portion and protruding downward relative to the thin plate portion. The thin plate portion is integrally formed with the thick plate portion.

[0176] In Figure 19 and Figure 20 , among the product regions M, the product region of the first metal plate 70 is set to M7, the product region of the second metal plate 80 is set to M8, and the product region of the third metal plate 90 is set to M9. In addition, in Figure 18 and Figure 19 , among the frame portions N, the frame portion of the first metal plate 70 is set to N7, the frame portion of the second metal plate 80 is set to N8, and the frame portion of the third metal plate 90 is set to N9.

[0177] Figure 20 is a cross-sectional view of the first metal plate 70 along lines A-A to lines I-I of Figure 19 (a). Specifically, Figure 20 (a) is a cross-sectional view of the first metal plate 70 along line A-A of Figure 19 (a). Figure 20 (b) is a cross-sectional view of the first metal plate 70 along line B-B of Figure 21 (a). Figure 19 (c) is a cross-sectional view of the first metal plate 70 along line C-C of Figure 21 (a). Figure 19 (d) is a cross-sectional view of the first metal plate 70 along line D-D of Figure 21 (a). Figure 19 (e) is a cross-sectional view of the first metal plate 70 along line E-E of Figure 21 (a). Figure 19 (f) is a cross-sectional view of the first metal plate 70 along line F-F of Figure 21 (a). Figure 19 (g) is a cross-sectional view of the first metal plate 70 along line G-G of Figure 21 (a). Figure 19(h) is a cross-sectional view of the first metal plate 70 along Figure 21 (a) taken along line H-H. Figure 19 (i) is a cross-sectional view of the first metal plate 70 along Figure 21 (a) taken along line I-I.

[0178] As shown in Figure 19 (a) and Figure 21 , the product region M7 of the first metal plate 70 has a conductor portion 71, a terminal portion 72, a connecting portion 73, a core portion 74, and support portions 751 and 752.

[0179] The conductor portion 71 is formed in a substantially rectangular spiral (substantially 3 / 4 turns) on the inner side of the product region M7, and is connected to the frame portion N7 by a plurality of connection portions 76 extending from the inner side of the product region M7 to the outer side of the product region M7. The number and connection positions of the connection portions 76 can be arbitrarily determined as long as the conductor portion 71 can be stably supported by the frame portion N7, but it is preferable to arrange them near the corners of the substantially rectangular conductor portion 71.

[0180] The terminal portion 72 is formed at a starting point 711 which is one end of the conductor portion 71, and the connecting portion 73 is formed at an ending point 712 which is the other end. The planar shape of the terminal portion 72 and the connecting portion 73 is, for example, a square or a rectangle. The conductor portion 71, the connection portions 76, and the frame portion N7 are thin plate portions formed to a predetermined thickness, and the terminal portion 72 and the connecting portion 73 are thick plate portions formed to the same thickness as the conductor portion 71 and the like. The terminal portion 72 and the connecting portion 73 are sometimes collectively referred to as end thick plate portions.

[0181] The terminal portion 72 is arranged on the inner side of the product region M7, and extends to the outer side of the product region M7 and is connected to the frame portion N7 on the opposite side of the connection portion of the starting point 711 of the conductor portion 71. The portion extending from the terminal portion 72 is a thin plate portion the same as the connection portions 76. The connecting portion 73 is arranged on the inner side of the product region M7, and extends to the outer side of the product region M7 and is connected to the frame portion N7 on the opposite side of the connection portion of the ending point 712 of the conductor portion 71. The portion extending from the connecting portion 73 is a thin plate portion the same as the connection portions 76. The edge of the frame portion N7 to which the connecting portion 73 is connected is adjacent to the edge of the frame portion N7 to which the terminal portion 72 is connected, and is a substantially perpendicular edge with respect to the edge.

[0182] The magnetic core portion 74 is arranged separately from the wire portion 71 on the inner side of the spiral formed by the wire portion 71. The magnetic core portion 74 is joined to the same side of the frame portion N7 as the side to which the joining portion 73 is connected, by a magnetic core connecting portion 77 extending from the inner side of the product region M7 to the outer side of the product region M7. In other words, the magnetic core portion 74 is supported by the frame portion N7 via the magnetic core connecting portion 77 provided in the region of the first metal plate 70 in which the wire portion 71 is not arranged. The magnetic core portion 74 is a thick plate portion formed to the same thickness as the terminal portion 72 and the joining portion 73, and is formed in a substantially square shape in the substantially central portion of the product region M7. The magnetic core connecting portion 77 is a thin plate portion formed to the same thickness as the wire portion 71 and the like. The magnetic core portion 74 is electrically independent from the wire portion 71. The magnetic core portion 74 is sometimes referred to as an inner thick plate portion.

[0183] The support portions 751 and 752 are arranged on the inner side of the product region M7, and extend to the outer side of the product region M7 on one side and are connected to the frame portion N7. The portions extending from the support portions 751 and 752 are thin plate portions the same as the connecting portion 76. The other sides of the support portions 751 and 752 are not connected to the wire portion 71. In other words, the support portions 751 and 752 are not electrically conducted with the wire portion 71. The support portions 751 and 752 constitute portions for supporting the thick plate portions of the other metal plate.

[0184] The support portion 751 is connected to the side of the frame portion N7 opposite the side to which the terminal portion 72 is connected. The support portion 752 is connected to the side of the frame portion N7 opposite the side to which the joining portion 73 is connected.

[0185] The upper surfaces (the surfaces on the second metal plate 80 side) of the wire portion 71, the connecting portion 76, the magnetic core connecting portion 77, and the frame portion N7 are located on substantially the same plane as the upper surfaces (the surfaces on the second metal plate 80 side) of the terminal portion 72, the joining portion 73, the magnetic core portion 74, and the support portions 751 and 752. On the other hand, the lower surfaces of the wire portion 71, the connecting portion 76, the magnetic core connecting portion 77, and the frame portion N7 are located in positions recessed toward the second metal plate 80 side with respect to the lower surfaces of the terminal portion 72, the joining portion 73, the magnetic core portion 74, and the support portions 751 and 752.

[0186] Note that the frame portion N7 can include a first portion having a thickness equal to that of the lead portion 71, and a second portion having a thickness equal to that of the terminal portion 72. For example, as the second portion, a reinforcing portion 78 can be provided at the four corners of the frame portion N7 in order to reinforce the frame portion N7 and prevent the metal plate from tilting. In this case, the lower surface of the reinforcing portion 78 is located on substantially the same plane as the lower surface of the terminal portion 72. The reinforcing portion 78 can be formed in an L shape, for example. Instead of the reinforcing portion 78, a second portion (thick plate portion) can be provided at portions other than the corners of the frame portion N7 in order to reinforce the frame portion N7 and prevent the metal plate from tilting, or the second portion (thick plate portion) can be further provided in addition to the reinforcing portion 78.

[0187] The thickness of the terminal portion 72, the connecting portion 73, the magnetic core portion 74, and the support portions 751 and 752 is about 50 μm to 500 μm, for example, and the thickness of the lead portion 71, the connecting portion 76, the magnetic core connecting portion 77, and the frame portion N7 is about half the thickness of the terminal portion 72, for example. Note that when the reinforcing portion 78 is provided on the frame portion N7, the thickness of the reinforcing portion 78 is equal to the thickness of the terminal portion 72.

[0188] As shown in Figure 19 (b), the product region M8 of the second metal plate 80 has a lead portion 81, a connecting portion 831, a connecting portion 832, a magnetic core portion 84, and support portions 851 and 852. The connecting portion 831 is formed at a starting point 811 which is one end of the lead portion 81, and the connecting portion 832 is formed at a terminal point 812 which is the other end.

[0189] The lead portion 81, the connecting portions 831 and 832, the magnetic core portion 84, and the support portions 851 and 852 of the second metal plate 80 are formed in the same pattern as the lead portion 71, the terminal portion 72, the connecting portion 73, the magnetic core portion 74, and the support portions 751 and 752 of the first metal plate 70. When the first metal plate 70 shown in Figure 19 (a) is rotated by 90 degrees in the clockwise direction, it overlaps Figure 21 (b) in a plan view. The thickness of the lead portion 81, the connecting portions 831 and 832, the magnetic core portion 84, and the support portions 851 and 852 of the second metal plate 80 is also equal to the thickness of the lead portion 71, the terminal portion 72, the connecting portion 73, the magnetic core portion 74, and the support portions 751 and 752 of the first metal plate 70.

[0190] As shown in Figure 19 (b), the product region M8 of the second metal plate 80 has a lead portion 81, a connecting portion 831, a connecting portion 832, a magnetic core portion 84, and support portions 851 and 852. The connecting portion 831 is formed at a starting point 811 which is one end of the lead portion 81, and the connecting portion 832 is formed at a terminal point 812 which is the other end.

[0189] The lead portion 81, the connecting portions 831 and 832, the magnetic core portion 84, and the support portions 851 and 852 of the second metal plate 80 are formed in the same pattern as the lead portion 71, the terminal portion 72, the connecting portion 73, the magnetic core portion 74, and the support portions 751 and 752 of the first metal plate 70. When the first metal plate 70 shown in Figure 19 (a) is rotated by 90 degrees in the clockwise direction, it overlaps Figure 21 (b) in a plan view. The thickness of the lead portion 81, the connecting portions 831 and 832, the magnetic core portion 84, and the support portions 851 and 852 of the second metal plate 80 is also equal to the thickness of the lead portion 71, the terminal portion 72, the connecting portion 73, the magnetic core portion 74, and the support portions 751 and 752 of the first metal plate 70.

[0190] As shown in Figure 19 (b), the product region M8 of the second metal plate 80 has a lead portion 81, a connecting portion 831, a connecting portion 832, a magnetic core portion 84, and support portions 851 and 852. The connecting portion 831 is formed at a starting point 811 which is one end of the lead portion 81, and the connecting portion 832 is formed at a terminal point 812 which is the other end.

[0191] The conductor portion 91, the terminal portion 92, the connecting portion 93, the magnetic core portion 94, and the support portions 951 and 952 of the third metal plate 90 are formed in the same pattern as the conductor portion 71, the terminal portion 72, the connecting portion 73, the magnetic core portion 74, and the support portions 751 and 752 of the first metal plate 70. When the first metal plate 70 shown in (a) is rotated 180 degrees in the clockwise direction, it overlaps the third metal plate 90 shown in (a) in the plan view. The thicknesses of the conductor portion 91, the terminal portion 92, the connecting portion 93, the magnetic core portion 94, and the support portions 951 and 952 of the third metal plate 90 are also the same as the thicknesses of the conductor portion 71, the terminal portion 72, the connecting portion 73, the magnetic core portion 74, and the support portions 751 and 752 of the first metal plate 70. Figure 19 Figure 19

[0192] As described above, since the first metal plate 70, the second metal plate 80, and the third metal plate 90 are formed in the same pattern, the metal plates are stacked while being rotated 90 degrees each to form the coil structure 3.

[0193] Figure 20 (a) is a cross-sectional view of the coil structure 3 along the line A-A of (a). Figure 19 (a) is a cross-sectional view of the coil structure 3 along the line B-B of (a). Figure 20 (a) is a cross-sectional view of the coil structure 3 along the line C-C of (a). Figure 22 (a) is a cross-sectional view of the coil structure 3 along the line D-D of (a). Figure 19 (a) is a cross-sectional view of the coil structure 3 along the line E-E of (a). Figure 22 (a) is a cross-sectional view of the coil structure 3 along the line F-F of (a). Figure 19 (a) is a cross-sectional view of the coil structure 3 along the line G-G of (a). Figure 23 (a) is a cross-sectional view of the coil structure 3 along the line H-H of (a). Figure 19 (a) is a cross-sectional view of the coil structure 3 along the line I-I of (a). Note that, in (b), the representation of a part of the symbols is omitted for convenience. Figure 23 Figure 19 (a) is a cross-sectional view of the coil structure 3 along the line J-J of (a). Figure 24 (a) is a cross-sectional view of the coil structure 3 along the line K-K of (a). Figure 19 (a) is a cross-sectional view of the coil structure 3 along the line L-L of (a). Figure 24 (a) is a cross-sectional view of the coil structure 3 along the line M-M of (a). Figure 19 (a) is a cross-sectional view of the coil structure 3 along the line N-N of (a). Figure 25 (a) is a cross-sectional view of the coil structure 3 along the line O-O of (a). Figure 19 (a) is a cross-sectional view of the coil structure 3 along the line P-P of (a). Figure 25 (a) is a cross-sectional view of the coil structure 3 along the line Q-Q of (a). Note that, in (b), the representation of a part of the symbols is omitted for convenience. Figure 19

[0194] (a) is a cross-sectional view of the coil structure 3 along the line R-R of (a). Figure 26 (a) is a cross-sectional view of the coil structure 3 along the line S-S of (a). Figure 19 ​​​​As shown, in the coil structure 3, the adjacent metal plates are joined to each other. The adjacent metal plates can be joined to each other, for example, by diffusion joining.

[0195] Specifically, the second metal plate 80 is stacked on the first metal plate 70, and the thick plate portions thereof are joined to each other. That is, the support portion 851 is joined on the terminal portion 72, the link portion 93 is stacked on the link portion 831, the support portion 952 is stacked on the support portion 851, and the terminal portion 92 is stacked on the support portion 852. In addition, the magnetic core portion 94 is joined on the magnetic core portion 84. In addition, each of the reinforcing portions 98 is joined on each of the reinforcing portions 88.

[0196] Thus, the link portion 832 connected to the terminal point 812 of the wire portion 81 and the link portion 93 connected to the start point 911 of the wire portion 91 are conducted, and the wire portion 81 and the wire portion 91 are connected in series. In addition, since the wire portion 81 and the wire portion 91 are formed thinner than the terminal portion 72 or the link portion 831 and the like, the upper surface of the wire portion 81 does not contact the lower surface of the wire portion 91. In addition, since any one of the thick plate portions of the second metal plate 80 is necessarily arranged on the lower side of each of the thick plate portions of the third metal plate 90, the metal plates can be easily joined to each other.

[0197] Similarly, the third metal plate 90 is stacked on the second metal plate 80, and the thick plate portions thereof are joined to each other. That is, the support portion 951 is joined on the link portion 831, the link portion 93 is stacked on the link portion 832, the support portion 952 is stacked on the support portion 851, and the terminal portion 92 is stacked on the support portion 852. In addition, the magnetic core portion 94 is joined on the magnetic core portion 84. In addition, each of the reinforcing portions 98 is joined on each of the reinforcing portions 88.

[0198] Thus, the link portion 832 connected to the terminal point 812 of the wire portion 81 and the link portion 93 connected to the start point 911 of the wire portion 91 are conducted, and the wire portion 81 and the wire portion 91 are connected in series. In addition, since the wire portion 81 and the wire portion 91 are formed thinner than the terminal portion 72 or the link portion 831 and the like, the upper surface of the wire portion 81 does not contact the lower surface of the wire portion 91. In addition, since any one of the thick plate portions of the second metal plate 80 is necessarily arranged on the lower side of each of the thick plate portions of the third metal plate 90, the metal plates can be easily joined to each other.

[0199] With the above structure, in the coil structure 3, the terminal point 712 of the wire portion 71 and the start point 811 of the wire portion 81, and the terminal point 812 of the wire portion 81 and the start point 911 of the wire portion 91 are sequentially connected. Thus, one spiral coil is formed from the start point 711 of the wire portion 71 to the terminal point 912 of the wire portion 91. In addition, in the coil structure 3, the magnetic core portions 74, 84, and 94 are sequentially stacked, thereby forming the magnetic core C inside the one spiral coil.

[0200] Also, as with the first embodiment, the inductor 4 of the surface mounting type shown in FIG. 1 is manufactured by covering the coil structure 3 with the encapsulation resin 150 in a manner such that the portion to be an external connection terminal is exposed. Figures 22-26 The planar shape of the inductor 4 is, for example, a rectangular shape such as a square or a long rectangle.

[0201] The side surface and the lower surface of the terminal portion 72 exposed from the encapsulation resin 150, the side surface of the support portion 851, and the side surface of the support portion 952 become the external connection terminals 1A. Also, the side surface and the lower surface of the support portion 752 exposed from the encapsulation resin 150, the side surface of the support portion 852, and the side surface of the terminal portion 92 become the external connection terminals 1B.

[0202] Note that, Figures 18-21 (b) is a view of Figures 22-26 (a) viewed from the lower surface side. In other words, Figure 27 (b) is a view of Figure 27 (a) upside down by rotating 180 degrees in the paper front-rear direction. The planar shape of the inductor 4 can be, for example, approximately 3 mm x 3 mm of a substantially rectangular shape. The thickness of the inductor 4 can be, for example, approximately 1.0 mm.

[0203] Figure 27 is a cross-sectional view for explaining a mounting method of the inductor according to the modified example 1 of the first embodiment, Figure 27 (a) shows Figure 27 J cross section of Figure 28 (b) shows Figure 28 K cross section of Figure 27 (a) and Figure 28 Figure 27 Figure 28 Figure 28 (b), the inductor 4 is mounted on the substrate 200. Specifically, a pad 210 is formed on one surface of the substrate 200, and a portion of the upper surface of the pad 210 is exposed within an opening portion 220x of a solder resist layer 220. The upper surface of the pad 210 exposed within the opening portion 220x is electrically connected to the external connection terminals 1A and 1B of the inductor 4 by solder 230.

[0204] In this way, in the coil structure 3, the wire portion, the end thick plate portion, and the inner thick plate portion of each metal plate are formed in the same pattern, and the metal plates are stacked while being rotated 90 degrees each. With this structure, a 2-layer or 3-layer coil structure can be easily formed. As for other effects, the same as the first embodiment.

[0205] Although the above-described preferred embodiments and the like are described in detail, the embodiments and the like are not limited to the above-described embodiments and the like, and various modifications and substitutions can be made to the embodiments and the like without departing from the scope recited in the claims.

[0206] For example, the planar shape of the lead portion and the frame portion of each metal plate is not limited to a substantially rectangular shape, and can be a circular shape, an elliptical shape, or another more complex shape.

Claims

1. A coil structure in which a plurality of metal plates are stacked, wherein each of the metal plates includes: a spiral-shaped conductor portion; an end portion thick plate portion formed thicker than the conductor portion at both ends of the conductor portion; and an inner side thick plate portion formed to the same thickness as the end portion thick plate portion and arranged apart from the conductor portion on an inner side of a spiral formed by the conductor portion, the plurality of metal plates are stacked, one of the end portion thick plate portions of adjacent metal plates are joined to each other, a spiral-shaped coil in which the conductor portions of the respective metal plates are connected in series is formed, and the inner side thick plate portions of adjacent metal plates are joined to each other to form a magnetic core.

2. The coil structure according to claim 1, wherein each of the metal plates includes a support portion formed to the same thickness as the end portion thick plate portion and arranged on an outer side of the spiral formed by the conductor portion, the support portion is electrically independent of the conductor portion, and the support portion of one of the adjacent metal plates is joined to the end portion thick plate portion or the support portion of the other of the adjacent metal plates.

3. The coil structure according to claim 2, wherein the end portion thick plate portion on one end side of the conductor portions connected in series and the support portion of another metal plate stacked with the end portion thick plate portion on one end side, and the end portion thick plate portion on the other end side of the conductor portions connected in series and the support portion of another metal plate stacked with the end portion thick plate portion on the other end side constitute external connection terminals.

4. The coil structure according to any one of claims 1 to 3, comprising: a plurality of product regions arranged in a plan view and constituting inductors when singulated; and frame portions supporting each of the product regions from a peripheral side, the conductor portion, the end portion thick plate portion, and the inner side thick plate portion of each of the metal plates are formed in each of the product regions.

5. The coil structure according to claim 4, wherein the inner side thick plate portion is supported by the frame portion via a connection portion formed to the same thickness as the conductor portion.

6. The coil structure according to claim 4, wherein the frame portion is formed in a frame shape in which each side is equal in length, the conductor portion, the end portion thick plate portion, and the inner side thick plate portion of each of the metal plates are formed in the same pattern, and the metal plates are stacked while each of the metal plates is rotated by 90 degrees.

7. The coil structure according to claim 4, wherein the frame portion includes a first portion having the same thickness as the conductor portion, and a second portion having the same thickness as the end portion thick plate portion and the inner side thick plate portion.

8. An inductor comprising: the coil structure according to any one of claims 1 to 7; and a packaging resin covering the coil structure in a manner in which a part of the end portion thick plate portion on one end side of the conductor portions connected in series and a part of the end portion thick plate portion on the other end side of the conductor portions connected in series are exposed.

9. A lead frame comprising: a spiral-shaped conductor portion; ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ an end thick plate portion formed thicker than the wire portion at both ends of the wire portion; an inner thick plate portion formed to the same thickness as the end thick plate portion and arranged separately from the wire portion on the inner side of the spiral formed by the wire portion, the inner thick plate portion constituting a magnetic core; and a frame portion connected directly or indirectly to the wire portion, the end thick plate portion, and the inner thick plate portion, wherein a part of the end thick plate portion on one end side of the wire portion and a part of the end thick plate portion on the other end side of the wire portion are exposed from the packaging resin, the inner thick plate portion is connected to the frame portion via a magnetic core connection portion having the same thickness as the wire portion.

10. A method for manufacturing a coil structure in which a plurality of metal plates are stacked, the method comprising: a step of patterning a metal plate to form a plurality of metal plates including a spiral wire portion, an end thick plate portion formed thicker than the wire portion at both ends of the wire portion, and an inner thick plate portion formed to the same thickness as the end thick plate portion and arranged separately from the wire portion on the inner side of the spiral formed by the wire portion; and a step of stacking the metal plates, wherein in the stacking step, the metal plates are stacked in a manner such that one of the end thick plate portions of adjacent metal plates are joined to each other, a spiral coil in which the wire portions of the metal plates are connected in series is formed, and the inner thick plate portions of adjacent metal plates are joined to each other to form a magnetic core.

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