Stacked coil component

Abstract

To provide a stacked coil component having a high Q value.SOLUTION: A stacked coil component 1 includes a coil form 2, a coil 3, external electrodes 41, 42, and connection conductors 51, 52. Coil conductors 31, 32 and coil conductors 36, 37 respectively constitute a connection part 3a and a connection part 3f. A plurality of coil conductors 30 constitute a plurality of connection parts (3b, 3c, 3d, 3e). In the connection parts 3a, 3f, the coil conductors 31, 37 overlap and physically connected to the coil conductors 32, 36. In the plurality of connection parts (3b, 3c, 3d, 3e), the coil conductors adjacent to each other of the plurality of coil conductors 30 are overlapped and physically connected to each other. The coil conductors 31, 37 has a path length longer than a path length of the coil conductors 32, 36. An area of the connection parts 3a, 3f when viewed from one direction is larger than the smallest area of areas of the plurality of connection part 3b, 3c, 3d, 3e when viewed from the one direction.SELECTED DRAWING: Figure 2

Description

Technical Field

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

Background Art

[0002] A multilayer coil component including a body, a coil disposed within the body, an external electrode disposed on the surface of the body, and a connection conductor disposed within the body is known (for example, Patent Document 1). The connection conductor electrically connects the coil and the external electrode to each other. The coil includes a first coil conductor located in the same layer as the connection conductor and a plurality of coil conductors arranged in one direction. The plurality of coil conductors includes a second coil conductor adjacent to the first coil conductor in one direction.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] An aspect of the present invention aims to provide a multilayer coil component capable of improving the Q value.

Means for Solving the Problems

[0005] A multilayer coil component according to one aspect of the present invention includes a base body, a coil disposed within the base body, an external electrode disposed on the surface of the base body, and a connection conductor disposed within the base body. The connection conductor electrically connects the coil and the external electrode to each other. The coil includes a first coil conductor and a plurality of coil conductors. The first coil conductor is located at an end of the coil and is included in the same layer as the connection conductor. The plurality of coil conductors includes a second coil conductor that is adjacent to the first coil conductor in one direction and is arranged in the one direction. The first coil conductor has a path length longer than the path length of the second coil conductor. The first coil conductor and the second coil conductor constitute a first connection portion that overlaps with each other and is physically connected. Adjacent coil conductors among the plurality of coil conductors constitute a plurality of second connection portions that overlap with each other and are physically connected. The area of the first connection portion viewed from one direction is larger than the smallest area among the areas of the plurality of second connection portions viewed from one direction.

[0006] The Q value of the multilayer coil component is proportional to the reciprocal of the electrical resistance. The electrical resistance of a coil having a plurality of coil conductors depends on the combined resistance of each coil conductor and the connection portions where adjacent coil conductors are connected. Since the electrical resistance of a conductor is proportional to the length of the conductor and inversely proportional to the cross-sectional area of the conductor, the electrical resistance in the plurality of coil conductors varies according to the length of the path length of the coil conductors and the area where adjacent coil conductors overlap and are physically connected. Therefore, the Q value of the multilayer coil component depends on the path length of the plurality of coil conductors constituting the coil and the area of the connection portions.

[0007] In a multilayer coil component, a plurality of inductance values are required for a given external dimension. Since the inductance value depends on the number of turns of the coil, it is difficult to determine the path length of each of the plurality of coil conductors constituting the coil to be constant. The path length of each of the plurality of coil conductors is determined so that adjacent coil conductors do not form a loop. A connection portion where a coil conductor having a path length longer than that of other coil conductors is connected to an adjacent coil conductor may have a larger area than the area of a connection portion where other coil conductors are connected.

[0008] In the above-described one aspect, since the first coil conductor is located at the end of the coil, it is adjacent to the coil conductor only in one direction and in one orientation. Since the first coil conductor is not adjacent to the coil conductor in the other orientation, the path length is determined so that a loop is not formed only between the first coil conductor and the second coil conductor. The path length of the second coil conductor is determined so that a loop is not formed between both the first coil conductor and a coil conductor adjacent to the first coil conductor in a different orientation. Since the constraint required for the path length of the first coil conductor is less than the constraint required for the path length of the second coil conductor, the path length of the first coil conductor can be extended more than the path length of the second coil conductor. As a result, the first coil conductor has a path length longer than the path length of the second coil conductor. The area of the first connection portion as viewed from one direction is larger than the smallest area among the areas of the plurality of second connection portions as viewed from one direction. Therefore, the electrical resistance of the first connection portion is smaller than the electrical resistance in the second connection portion having the smallest area among the plurality of second connection portions. As a result, the combined resistance of the first coil conductor, the first connection portion, the plurality of coil conductors, and the plurality of second connection portions in the above-described one aspect is smaller than the combined resistance in a configuration in which the first connection portion has an area equal to or smaller than the smallest area among the plurality of second connection portions. Therefore, the above-described one aspect can improve the Q value of the multilayer coil component.

[0009] A multilayer coil component according to another aspect of the present invention includes a base body, a coil disposed within the base body, an external electrode disposed on the surface of the base body, and a connection conductor disposed within the base body. The connection conductor electrically connects the coil and the external electrode to each other. The coil includes a first coil conductor and a plurality of coil conductors. The first coil conductor is located at an end of the coil and is included in the same layer as the connection conductor. The plurality of coil conductors includes a second coil conductor adjacent to the first coil conductor in one direction, and are arranged in the one direction. The first coil conductor has a path length longer than that of the second coil conductor. The first coil conductor and the second coil conductor form a first connection portion that overlaps and is physically connected to each other. Adjacent coil conductors among the plurality of coil conductors form a plurality of second connection portions that overlap and are physically connected to each other. The first connection portion has a path length longer than the shortest path length among the path lengths of the plurality of second connection portions.

[0010] The Q value of the multilayer coil component is proportional to the reciprocal of the electrical resistance. The electrical resistance of a coil having a plurality of coil conductors depends on the combined resistance of the connection portions where adjacent coil conductors are connected and the portions of the adjacent coil conductors that are not included in the connection portions. The electrical resistance of a conductor is proportional to the length of the conductor and inversely proportional to the thickness of the conductor. The connection portion where adjacent coil conductors overlap and are physically connected to each other has a thickness larger than the thickness of the portions of the adjacent coil conductors that are not included in the connection portion. Therefore, the connection portion where adjacent coil conductors overlap and are physically connected to each other has an electrical resistance smaller than the electrical resistance of the portions of the adjacent coil conductors that are not included in the connection portion. As a result, the Q value of the multilayer coil component depends on the path length of the connection portion where adjacent coil conductors are connected and the path length of the portions of the adjacent coil conductors that are not included in the connection portion.

[0011] For a multilayer coil component, a plurality of inductance values are required for a given external dimension. Since the inductance value depends on the number of turns of the coil, it is difficult to determine the path length of each of the plurality of coil conductors that make up the coil with certainty. The path length of each of the plurality of coil conductors is determined so that adjacent coil conductors do not form a loop. A connection portion where a coil conductor having a longer path length than other coil conductors is connected to an adjacent coil conductor may have a longer path length than the path length of a connection portion where other coil conductors are connected to each other.

[0012] In the above another aspect, since the first coil conductor is located at the end of the coil, it is adjacent to the coil conductor only in one direction in one orientation. Since the first coil conductor is not adjacent to the coil conductor in the other orientation, the path length is determined so that a loop is not formed only between the first coil conductor and the second coil conductor. The path length of the second coil conductor is determined so that a loop is not formed between the first coil conductor and a coil conductor adjacent to the first coil conductor in a different orientation. Since the constraints required for the path length of the first coil conductor are fewer than the constraints required for the path length of the second coil conductor, the path length of the first coil conductor can be extended more than the path length of the second coil conductor. As a result, the first coil conductor has a longer path length than the path length of the second coil conductor. The first connection portion has a path length longer than the shortest path length among the path lengths of the plurality of second connection portions. For example, the shortest second connection portion has the shortest path length among the path lengths of the plurality of second connection portions. Therefore, the path length of the portion not included in the first connection portion of the first coil conductor and the path length of the portion not included in the first connection portion of the second coil conductor are shorter than the path length of the portion not included in the shortest second connection portion of the adjacent coil conductors. As a result, the combined resistance of the first coil conductor, the first connection portion, the plurality of coil conductors, and the plurality of second connection portions in the above one aspect is smaller than the combined resistance in a configuration where the first connection portion has a path length equal to or less than the path length of the shortest second connection portion. Therefore, the above one aspect enables improvement of the Q value of the multilayer coil component.

Advantages of the Invention

[0013] Aspects of the present invention provide a multilayer coil component capable of improving the Q value.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Embodiments for Carrying Out the Invention

[0015] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description of the drawings, the same or corresponding elements are denoted by the same reference numerals, and redundant descriptions are omitted as appropriate.

[0016] Referring to FIGS. 1 to 4, the configuration of the multilayer coil component 1 according to the present embodiment will be described. FIG. 1 is a perspective view of the multilayer coil component according to the present embodiment. FIG. 2 is a perspective view of the coil according to the present embodiment. FIG. 3 is a plan view of the coil according to the present embodiment as viewed from the side surface 2e shown in FIG. 1. FIG. 4 is a plan view of the coil according to the present embodiment as viewed from the main surface 2b shown in FIG. 1. The multilayer coil component 1 according to the present embodiment is solder-mounted on an electronic device. The electronic device includes, for example, a circuit board or an electronic component.

[0017] As shown in FIGS. 1 and 2, the multilayer coil component 1 includes a body 2, a coil 3 disposed within the body 2, a pair of external electrodes 41, 42 disposed on the surface of the body 2, and a pair of connection conductors 51, 52 disposed within the body 2. The external electrodes 41, 42 are electrically connected to the coil 3. The body 2 has a rectangular parallelepiped shape. The rectangular parallelepiped shape includes a rectangular parallelepiped shape with chamfered corners and edges, and a rectangular parallelepiped shape with rounded corners and edges.

[0018] The body 2 has a pair of main surfaces 2a, 2b facing each other, a pair of side surfaces 2c, 2d, and a pair of side surfaces 2e, 2f. The main surfaces 2a, 2b, the side surfaces 2c, 2d, and the side surfaces 2e, 2f have a rectangular shape. The main surfaces 2a, 2b are adjacent to the side surfaces 2c, 2d and the side surfaces 2e, 2f. The side surfaces 2c, 2d and the side surfaces 2e, 2f are adjacent to each other. When the multilayer coil component 1 is solder-mounted on an electronic device, the main surface 2a faces the electronic device to be solder-mounted. The main surfaces 2a, 2b, the side surfaces 2c, 2d, and the side surfaces 2e, 2f are flat surfaces. The flat surface means a surface formed aiming at a plane and is not limited to a geometrically perfect plane. The flat surface may include curvatures and irregularities generated in the manufacturing process.

[0019] The direction D3 in which the pair of main surfaces 2a and 2b face each other is orthogonal to the main surfaces 2a and 2b respectively. The direction D1 in which the pair of side surfaces 2c and 2d face each other is orthogonal to the side surfaces 2c and 2d respectively. The direction D2 in which the pair of side surfaces 2e and 2f face each other is orthogonal to the side surfaces 2e and 2f respectively. The direction D3 is orthogonal to the direction D1 and the direction D2. The direction D1 and the direction D2 are orthogonal to each other. In the element body 2, a pair of depressions corresponding to the pair of external electrodes 41 and 42 are formed.

[0020] The external electrodes 41 and 42 have an L-shaped cross section when viewed from the direction D1. The depressions corresponding to the external electrodes 41 and 42 formed in the element body 2 have an L shape when viewed from the direction D1. The external electrode 41 includes a portion 41a and a portion 41b. The surface of the portion 41a faces the same direction as the side surface 2e, and the surface of the portion 41b faces the same direction as the main surface 2a. The portion 41a and the portion 41b are continuous along the ridge line portion between the side surface 2e and the main surface 2a. The external electrode 42 includes a portion 42a and a portion 42b. The surface of the portion 42a faces the same direction as the side surface 2f, and the surface of the portion 42b faces the same direction as the main surface 2a. The portion 42a and the portion 42b are continuous along the ridge line portion between the side surface 2f and the main surface 2a.

[0021] In this embodiment, the length of the external electrodes 41 and 42 in the direction D3 is longer than the length of the external electrodes 41 and 42 in the direction D2. The portions 41b and 42b are arranged so as to be exposed in the same direction as the main surface 2a. The surfaces of the portions 41b and 42b and the main surface 2a may be located on the same plane. The surfaces of the portions 41b and 42b may protrude from the main surface 2a. The portion 41a is arranged so as to be exposed in the same direction as the side surface 2e. The surface of the portion 41a and the side surface 2e may be located on the same plane. The surface of the portion 41a may protrude from the side surface 2e. The portion 42a is arranged on the side surface 2f so as to be exposed in the same direction as the side surface 2f. The surface of the portion 42a and the side surface 2f may be located on the same plane. The surface of the portion 42a may protrude from the side surface 2f. In this embodiment, the length of the portions 41a and 42a in the direction D3 is longer than the length of the portions 41b and 42b in the direction D2.

[0022] As shown in FIGS. 2 to 4, the coil 3 includes coil conductors 31 and 37 and a plurality of coil conductors 30. The coil conductors 31 and 37 and the plurality of coil conductors 30 are electrically connected to each other. The number of turns of the coil 3 is 2.5 turns. The coil conductors 31 and 37 and each coil conductor 30 constitute a part of the annular orbit in the coil 3. The coil conductors 31 and 37 and each coil conductor 30 exhibit, for example, a shape in which a part of the loop is interrupted. The coil conductors 31 and 37 and each coil conductor 30 have a path length and a thickness, respectively.

[0023] The coil conductors 31 and 37 are located at the ends of the coil 3. In this embodiment, the coil conductor 31 is located at one end of the coil 3 in the direction D1, and the coil conductor 37 is located at the other end of the coil 3 in the direction D1. The coil conductor 31 is included in the same layer as the connection conductor 51, and the coil conductor 37 is included in the same layer as the connection conductor 52. The plurality of coil conductors 30 are arranged side by side in the direction D1. The plurality of coil conductors 30 include coil conductors 32, 33, 34, 35, and 36 that are arranged in that order along the direction D1. The coil conductor 32 is adjacent to the coil conductor 31 in the direction D1, and the coil conductor 36 is adjacent to the coil conductor 37 in the direction D1. The coil conductors 32 and 36 are adjacent to the coil conductors 31 and 37 in the direction D1. The coil conductors 31 and 37 are defined as the first coil conductors. The coil conductors 32 and 36 are defined as the second coil conductors.

[0024] The widths of the coil conductors 31 and 37 and each coil conductor 30 in the direction orthogonal to the path are equal to each other. The thicknesses of the coil conductors 31 and 37 and each coil conductor 30 are equal to each other. In this specification, "equal" does not necessarily mean only that the values match. Even if there are slight differences, manufacturing errors, or measurement errors within a preset range included in the values, the values may be considered equal. Each layer of the coil conductors 31 and 37 and each coil conductor 32 to 36 corresponds to each layer constituting the laminated coil component 1. Each layer of the coil conductors 31 and 37 and each coil conductor 32 to 36 extends along a plane intersecting the direction D1 in which the coil conductors 31 and 37 and each coil conductor 32 to 36 are arranged. In this embodiment, each layer of the coil conductors 31 and 37 and each coil conductor 32 to 36 extends along the directions D2 and D3.

[0025] The coil conductors 31, 37 and each of the coil conductors 32 to 36 include a first end corresponding to one end in a shape where a part of the loop is interrupted, and a second end corresponding to the other end in a shape where a part of the loop is interrupted. The coil conductors 31, 37 and each of the coil conductors 32 to 36 extend along the path from the first end to the second end in their respective layers of the coil conductors 31, 37 and each of the coil conductors 32 to 36. The length of the path from the first end to the second end of the coil conductors 31, 37 and each of the coil conductors 32 to 36 is referred to as the path length of the coil conductors 31, 37 and each of the coil conductors 32 to 36.

[0026] The connection conductor 51 electrically connects the coil 3 and the external electrode 41 to each other. The coil 3 and the external electrode 41 are physically connected to each other via the connection conductor 51. The connection conductor 51 is continuous with the coil conductor 31 in the same layer as the coil conductor 31. The connection conductor 51 extends between the first end of the coil conductor 31 and the portion 41a of the external electrode 41. The thickness of the connection conductor 51 is equal to the thickness of the coil conductor 31. The connection conductor 52 electrically connects the coil 3 and the external electrode 42 to each other. The coil 3 and the external electrode 42 are physically connected to each other via the connection conductor 52. The connection conductor 52 is continuous with the coil conductor 37 in the same layer as the coil conductor 37. The connection conductor 52 extends between the second end of the coil conductor 37 and the portion 42a of the external electrode 42. The thickness of the connection conductor 52 is equal to the thickness of the coil conductor 37. The respective thicknesses of the connection conductor 51 and the connection conductor 52 are equal to each other.

[0027] FIG. 5 is an exploded view showing the configuration of the multilayer coil component 1 according to the present embodiment. In the present embodiment, the stacking direction of the multilayer coil component 1 is along the direction D1. FIG. 5 shows a plurality of layers constituting the multilayer coil component 1 as viewed from the direction D1. The plurality of layers constituting the multilayer coil component 1 include the layer constituting the base body 2, the layer constituting the coil 3, the layers constituting the external electrodes 41 and 42, and the layers constituting the connection conductors 51 and 52. The thicknesses of the plurality of layers are equal to each other. Hereinafter, with reference to FIG. 5, the base body 2, the coil 3, the external electrodes 41 and 42, and the connection conductors 51 and 52 will be described.

[0028] The base body 2 is composed of a plurality of stacked insulator layers 20. In the present embodiment, the number of the plurality of insulator layers 20 is "9". FIG. 5 shows seven insulator layers 20 with one insulator layer 20 located at each end in the direction D1 omitted. In the actual base body 2, each insulator layer 20 is integrated to such an extent that the boundary between each insulator layer 20 cannot be visually recognized. Each insulator layer 20 is made of, for example, a non-magnetic material. The non-magnetic material includes, for example, a glass ceramic material or a dielectric material. In the present embodiment, each insulator layer 20 is composed of a sintered body of a green sheet containing a non-magnetic material. Each insulator layer 20 may be made of a magnetic material.

[0029] The external electrodes 41 and 42 are respectively composed of a plurality of stacked electrode layers 410 and 420. In the present embodiment, the number of each of the plurality of electrode layers 410 and 420 is "7". In the actual external electrode 41, each electrode layer 410 is integrated to such an extent that the boundary between each electrode layer 410 cannot be visually recognized. In the actual external electrode 42, each electrode layer 420 is integrated to such an extent that the boundary between each electrode layer 420 cannot be visually recognized. Each of the electrode layers 410 and 420 is provided in a defect formed in the corresponding insulator layer 20. A pair of depressions corresponding to the external electrodes 41 and 42 are obtained by the defects formed in each insulator layer 20. Each of the electrode layers 410 and 420 is made of, for example, a conductive material. The conductive material includes, for example, Ag or Pd. In the present embodiment, each of the electrode layers 410 and 420 is composed of a sintered body of a conductive paste containing a powder of a conductive material.

[0030] The connection conductors 51 and 52 are respectively composed of electrode layers 510 and 520. The electrode layer 510 is continuous with the coil conductor layer 310, and the electrode layer 520 is continuous with the coil conductor layer 370. Each of the electrode layers 510 and 520 is provided in a defect formed in the corresponding insulator layer 20. Each of the electrode layers 510 and 520 is made of, for example, the same material as each of the electrode layers 410 and 420. Each of the electrode layers 510 and 520 is composed of, for example, a sintered body of a conductive paste.

[0031] The coil 3 is composed of a plurality of coil conductor layers. The coil conductor 31 is composed of the coil conductor layer 310. The coil conductor 32 is composed of the coil conductor layer 320. The coil conductor 33 is composed of the coil conductor layer 330. The coil conductor 34 is composed of the coil conductor layer 340. The coil conductor 35 is composed of the coil conductor layer 350. The coil conductor 36 is composed of the coil conductor layer 360. The coil conductor 37 is composed of the coil conductor layer 370. Each of the coil conductor layers 310 to 370 is provided in a defective portion formed in the corresponding insulator layer 20. Each of the coil conductor layers 310 to 370 is composed of, for example, the same material as each of the electrode layers 410 and 420. Each of the coil conductor layers 310 to 370 is composed of, for example, a sintered body of a conductive paste.

[0032] Hereinafter, the coil 3 will be described with reference to FIGS. 2 and 5 to 11. As shown in FIG. 5, the coil conductor layers 310 to 370 respectively correspond to the coil conductor 31, the coil conductors 32 to 36, and the coil conductor 37 viewed from the direction D1. FIG. 6 is a view showing adjacent coil conductors 31 and 32. FIG. 7 is a view showing adjacent coil conductors 32 and 33. FIG. 8 is a view showing adjacent coil conductors 33 and 34. FIG. 9 is a view showing adjacent coil conductors 34 and 35. FIG. 10 is a view showing adjacent coil conductors 35 and 36. FIG. 11 is a view showing adjacent coil conductors 36 and 37.

[0033] As viewed from direction D1, the coil 3 has a pentagonal shape. The pentagon is line-symmetric in direction D2 with respect to the center line along direction D3. The pentagon includes a first side located closest to the main surface 2b, a second side located closest to the side surface 2f, third and fourth sides located closest to the main surface 2a, and a fifth side located closest to the side surface 2e. The first side and the second side are connected at a first vertex, the second side and the third side are connected at a second vertex, the third side and the fourth side are connected at a third vertex, the fourth side and the fifth side are connected at a fourth vertex, and the fifth side and the first side are connected at a fifth vertex. The second side and the fifth side are line-symmetric to each other, and the third side and the fourth side are line-symmetric to each other with respect to the center line passing through the third vertex between the third side and the fourth side. The first side is longer than each of the second side and the fifth side. Each of the second side and the fifth side is longer than each of the third side and the fourth side.

[0034] As shown in FIG. 6, the path of the coil conductor 31 includes a part of the fifth side, the first side, the second side, the third side, the fourth side, and another part of the fifth side. The coil conductor 31 extends along the path from the end 31a to the end 31b. The path of the coil conductor 31 is illustrated by a two-dot chain line connecting the end 31a and the end 31b. The path length of the coil conductor 31 is 1 / 2 turn or more. The path of the coil conductor 32 includes a part of the first side, the second side, the third side, the fourth side, and a part of the fifth side. The coil conductor 32 extends along the path from the end 32a to the end 32b. The path of the coil conductor 32 is illustrated by a two-dot chain line connecting the end 32a and the end 32b. The path length of the coil conductor 32 is 1 / 2 turn or more. The coil conductor 31 and the coil conductor 32 are adjacent to each other in the direction D1. The coil conductor 31 and the coil conductor 32 form a connection part 3a that overlaps and is physically connected to each other. In the connection part 3a, a part including the end 31b of the coil conductor 31 and a part including the end 32a of the coil conductor 32 overlap in the direction D1. In the present embodiment, in the connection part 3a, a part including the end 31b of the coil conductor 31 and the whole of the coil conductor 32 overlap in the direction D1. In one example, in the connection part 3a, the end 31b of the coil conductor 31 and the end 32b of the coil conductor 32 overlap in the direction D1. The connection part 3a includes the whole of the coil conductor 32. The area of the connection part 3a seen from the direction D1 includes the area Sa. The path of the connection part 3a includes a part of the first side, the second side, the third side, the fourth side, and a part of the fifth side. The path of the connection part 3a is the same as the path of the coil conductor 32. The path of the connection part 3a is illustrated by a two-dot chain line connecting the end 32a and the end 31b. Seen from the direction D1, the connection part 3a curves between the first side and the second side, between the second side and the third side, between the third side and the fourth side, and between the fourth side and the fifth side. The connection part 3a is defined as the first connection part.

[0035] As shown in FIG. 7, the path of the coil conductor 33 includes a part of the second side, the third side, the fourth side, the fifth side, and a part of the first side. The coil conductor 33 extends along the path from the end 33a to the end 33b. The path of the coil conductor 33 is illustrated by a two-dot chain line connecting the end 33a and the end 33b. The path length of the coil conductor 33 is 1 / 2 turn or more. The coil conductor 32 and the coil conductor 33 are adjacent to each other in the direction D1. The coil conductor 32 and the coil conductor 33 form a connection part 3b that overlaps and is physically connected to each other. In the connection part 3b, a part including the end 32b of the coil conductor 32 and a part including the end 33a of the coil conductor 33 overlap in the direction D1. The area of the connection part 3b seen from the direction D1 includes the area Sb. The path of the connecting portion 3b includes a part of the second side, the third side, the fourth side, and a part of the fifth side. The path of the connecting portion 3b is illustrated by a two-dot chain line connecting the end 33a and the end 32b. When viewed from the direction D1, the connecting portion 3b curves between the second side and the third side, between the third side and the fourth side, and between the fourth side and the fifth side. The connecting portion 3b is defined as the second connecting portion.

[0036] As shown in FIG. 8, the path of the coil conductor 34 includes a part of the fifth side, the first side, and a part of the second side. The coil conductor 34 extends along the path from the end 34a to the end 34b. The path of the coil conductor 34 is illustrated by a two-dot chain line connecting the end 34a and the end 34b. The path length of the coil conductor 34 is 1 / 2 turn or less. The coil conductor 33 and the coil conductor 34 are adjacent to each other in the direction D1. The coil conductor 33 and the coil conductor 34 constitute a connecting portion 3c that overlaps and is physically connected to each other. In the connecting portion 3c, the portion including the end 33b of the coil conductor 33 and the portion including the end 34a of the coil conductor 34 overlap in the direction D1. The area of the connecting portion 3c when viewed from the direction D1 includes the area Sc. The path of the connecting portion 3c includes a part of the fifth side and a part of the first side. The path of the connecting portion 3c is illustrated by a two-dot chain line connecting the end 34a and the end 33b. When viewed from the direction D1, the connecting portion 3c curves between the fifth side and the first side. The connecting portion 3c is defined as the second connecting portion.

[0037] As shown in FIG. 9, the path of the coil conductor 35 includes a part of the first side, the second side, the third side, the fourth side, and a part of the fifth side. The coil conductor 35 extends along the path from the end 35a to the end 35b. The path of the coil conductor 35 is illustrated by a two-dot chain line connecting the end 35a and the end 35b. The path length of the coil conductor 35 is 1 / 2 turn or more. The coil conductor 35 and the coil conductor 32 have the same shape. The coil conductor 34 and the coil conductor 35 are adjacent to each other in the direction D1. The coil conductor 34 and the coil conductor 35 form a connection part 3d that overlaps and is physically connected to each other. In the connection part 3d, the part including the end 34b of the coil conductor 34 and the part including the end 35a of the coil conductor 35 overlap in the direction D1. The area of the connection part 3d viewed from the direction D1 includes the area Sd. The path of the connection part 3d includes a part of the first side and a part of the second side. The path of the connection part 3d is illustrated by a two-dot chain line connecting the end 35a and the end 34b. Viewed from the direction D1, the connection part 3d curves between the first side and the second side. The connection part 3d is defined as the second connection part.

[0038] As shown in FIG. 10, the path of the coil conductor 36 includes a part of the second side, the third side, the fourth side, the fifth side, and a part of the first side. The coil conductor 36 extends along the path from the end 36a to the end 36b. The path of the coil conductor 36 is illustrated by a two-dot chain line connecting the end 36a and the end 36b. The path length of the coil conductor 36 is 1 / 2 turn or more. The coil conductor 36 and the coil conductor 33 have the same shape. The coil conductor 35 and the coil conductor 36 are adjacent to each other in the direction D1. The coil conductor 35 and the coil conductor 36 form a connection part 3e that overlaps and is physically connected to each other. In the connection part 3e, the part including the end 35b of the coil conductor 35 and the part including the end 36a of the coil conductor 36 overlap in the direction D1. The area of the connection part 3e viewed from the direction D1 includes the area Se. The connection part 3e and the connection part 3b have the same shape. The path of the connection part 3e includes a part of the second side, the third side, the fourth side, and a part of the fifth side. The path of the connection part 3e is illustrated by a two-dot chain line connecting the end 36a and the end 35b. Viewed from the direction D1, the connection part 3e curves between the second side and the third side, between the third side and the fourth side, and between the fourth side and the fifth side. The connection part 3e is defined as the second connection part.

[0039] As shown in FIG. 11, the path of the coil conductor 37 includes a part of the second side, the third side, the fourth side, the fifth side, the first side, and another part of the second side. The coil conductor 37 extends along the path from end 37a to end 37b. The path of the coil conductor 37 is illustrated by a two-dot chain line connecting end 37a and end 37b. The path length of the coil conductor 31 is equal to or more than 1 / 2 turn. The coil conductor 36 and the coil conductor 37 are adjacent to each other in the direction D1. The coil conductor 36 and the coil conductor 37 form a connection part 3f that overlaps and is physically connected to each other. In the connection part 3f, the part including the end 36b of the coil conductor 36 and the part including the end 37a of the coil conductor 37 overlap in the direction D1. In the present embodiment, in the connection part 3f, the part including the end 37a of the coil conductor 37 and the whole of the coil conductor 36 overlap in the direction D1. In one example, in the connection part 3f, the end 36a of the coil conductor 36 and the end 37a of the coil conductor 37 overlap in the direction D1. The connection part 3f includes the whole of the coil conductor 36. The area of the connection part 3f viewed from the direction D1 includes the area Sf. The path of the connection part 3f includes a part of the second side, the third side, the fourth side, the fifth side, and a part of the first side. The path of the connection part 3f is the same as the path of the coil conductor 36. The path of the connection part 3f is illustrated by a two-dot chain line connecting end 37a and end 36b. Viewed from the direction D1, the connection part 3f curves between the second side and the third side, between the third side and the fourth side, between the fourth side and the fifth side, and between the fifth side and the first side. The connection part 3f is defined as the first connection part.

[0040] As described above, the connection parts 3a and 3f are defined as the first connection parts, and the connection parts 3b, 3c, 3d, and 3e are defined as a plurality of second connection parts. In this specification, "overlap" is not limited to a configuration in which the outer shapes of the overlapping parts coincide with each other. The parts including the ends 31b to 36b of the coil conductors 31 to 36 and the parts including the ends 32a to 37a of the coil conductors 32 to 37 may include parts that do not overlap in the direction D1. The parts including the ends 31b to 36b of the coil conductors 31 to 36 and the parts including the ends 32a to 37a of the coil conductors 32 to 37 may include parts that are not included in the connection parts 3a to 3f. The area Sa of the connection part 3a and the area Sf of the connection part 3f may be equal to each other. The area Sb of the connection part 3b and the area Se of the connection part 3e may be equal to each other. The area Sc of the connection part 3c and the area Sd of the connection part 3d may be equal to each other. The areas Sc and Sd are the smallest among the areas Sb, Sc, Sd, and Se. The areas Sa and Sf are larger than the areas Sc and Sd. The areas Sa and Sf are larger than any of the areas Sb, Sc, Sd, and Se. The path lengths of the connection parts 3a and 3f may be equal to each other. The path lengths of the connection parts 3b and 3e may be equal to each other. The path lengths of the connection parts 3c and 3d may be equal to each other. The path lengths of the connection parts 3c and 3d are the smallest among the path lengths of the connection parts 3b, 3c, 3d, and 3e. The path lengths of the connection parts 3a and 3f are larger than the path lengths of the connection parts 3c and 3d. The path lengths of the connection parts 3a and 3f are larger than any of the path lengths of the connection parts 3b, 3c, 3d, and 3e.

[0041] As described above, in the laminated coil component 1, since the coil conductors 31 and 37 are located at the ends of the coil 3, they are adjacent to the coil conductor only in one direction in the direction D1. Since the coil conductors 31 and 37 are not adjacent to the coil conductor in the other direction, the path length is determined so that a loop is not formed only between the coil conductors 32 and 36. The path lengths of the coil conductors 32 and 36 are determined so that a loop is not formed between both the coil conductors 31 and 37 and the coil conductors 33 and 35. Since the constraints required for the path lengths of the coil conductors 31 and 37 are fewer than the constraints required for the path lengths of the coil conductors 32 and 36, the path lengths of the coil conductors 31 and 37 can be extended more than the path lengths of the coil conductors 32 and 36. As a result, the coil conductors 31 and 37 have a longer path length than the path lengths of the coil conductors 32 and 36. The areas Sa and Sf of the connection portions 3a and 3f are larger than the smallest areas Sc and Sd among the areas Sb, Sc, Sd, and Se of the plurality of connection portions 3b, 3c, 3d, and 3e. Therefore, the electrical resistance of the connection portions 3a and 3f is smaller than the electrical resistance in the connection portions 3c and 3d having the smallest area. As a result, the combined resistance of the coil conductors 31 and 37, the connection portions 3a and 3f, the plurality of coil conductors 30, and the plurality of connection portions 3b, 3c, 3d, and 3e in the above one aspect is smaller than the combined resistance in a configuration where the connection portions 3a and 3f have an area equal to or smaller than the area of the connection portions 3c and 3d. Therefore, the multilayer coil component 1 can improve the Q value of the multilayer coil component.

[0042] In the multilayer coil component 1, the area of the connection portions 3a and 3f as viewed from the direction D1 is larger than any of the areas of the plurality of connection portions 3b, 3c, 3d, and 3e as viewed from one direction. In a configuration where the connection portions 3a and 3f have an area larger than any of the areas of the plurality of connection portions 3b, 3c, 3d, and 3e, the electrical resistance of the connection portions 3a and 3f is smaller than any of the electrical resistances of the plurality of connection portions 3b, 3c, 3d, and 3e. Therefore, the multilayer coil component 1 can further improve the Q value of the multilayer coil component.

[0043] In the multilayer coil component 1, since the coil conductors 31 and 37 are located at the ends of the coil 3, they are adjacent to the coil conductor in only one direction in the direction D1. Since the coil conductors 31 and 37 are not adjacent to the coil conductor in the other direction, the path length is determined so that a loop is not formed only between the coil conductors 32 and 36. The path length of the coil conductors 32 and 36 is determined so that a loop is not formed between both the coil conductors 31 and 37 and the coil conductors 33 and 35. Since the constraints on the path length of the coil conductors 31 and 37 are fewer than the constraints on the path length of the coil conductors 32 and 36, the path length of the coil conductors 31 and 37 can be extended more than the path length of the coil conductors 32 and 36. As a result, the coil conductors 31 and 37 have a path length longer than the path length of the coil conductors 32 and 36. The connection parts 3a and 3f have a path length longer than the shortest path length among the path lengths of the plurality of connection parts 3b, 3c, 3d, and 3e. In the multilayer coil component 1, the connection parts 3c and 3d have the shortest path length among the plurality of connection parts 3b, 3c, 3d, and 3e. Therefore, the path length of the portions of the coil conductors 31 and 37 that are not included in the connection parts 3a and 3f and the path length of the portions of the coil conductors 32 and 36 that are not included in the connection parts 3a and 3f are shorter than the path length of the portions of the adjacent coil conductors 33, 34, and 35 that are not included in the connection parts 3c and 3d. As a result, the combined resistance of the coil conductors 31 and 37, the connection parts 3a and 3f, the plurality of coil conductors 30, and the plurality of connection parts 3b, 3c, 3d, and 3e in the above one aspect is smaller than the combined resistance in a configuration where the connection parts 3a and 3f have a path length equal to or less than the path length of the connection parts 3c and 3d. Therefore, the above one aspect can improve the Q value of the multilayer coil component.

[0044] The path length of the connection parts 3a and 3f is longer than any of the path lengths of the plurality of connection parts 3b, 3c, 3d, and 3e. In a configuration where the connection parts 3a and 3f have a path length longer than any of the path lengths of the plurality of connection parts 3b, 3c, 3d, and 3e, the path length of the portions of the coil conductors 31 and 37 that are not included in the connection parts 3a and 3f and the path length of the portions of the coil conductors 32 and 36 that are not included in the connection parts 3a and 3f are shorter than any of the path lengths of the portions of the adjacent coil conductors of the plurality of coil conductors 30 that are not included in the connection parts 3b, 3c, 3d, and 3e. Therefore, the multilayer coil component 1 can further improve the Q value of the multilayer coil component.

[0045] The coil conductors 31 and 37 have a path length longer than any of the path lengths of the plurality of coil conductors 30. A configuration in which the path length of the coil conductors 31 and 37 is longer than any of the path lengths of the plurality of coil conductors 30 makes it easy to secure the area of the connection parts 3a and 3f and also makes it easy to secure the path length of the connection parts 3a and 3f.

[0046] The connection part 3a includes the entire coil conductor 32, and the connection part 3f includes the entire coil conductor 36. The configuration in which the connection portions 3a and 3f include the entire coil conductors 32 and 36 facilitates securing the area of the connection portions 3a and 3f and also facilitates securing the path length of the connection portions 3a and 3f.

[0047] The connection portions 3a and 3f are curved when viewed from the direction D1. Since the impedance becomes discontinuous at the curved portion of the coil conductor, loss due to reflection of high-frequency current can occur at the curved portion of the coil conductor. The configuration in which the connection portions 3a and 3f are curved when viewed from the direction D1 has a thickness in the direction D1 as compared with the configuration in which the coil conductor is curved when viewed from the direction D1, and thus loss is less likely to occur.

[0048] FIG. 12 is an exploded view showing the configuration of a multilayer coil component according to a modified example of the present embodiment. The multilayer coil component according to the modified example includes a coil 6 instead of the coil 3. Hereinafter, the coil 6 will be described with reference to FIG. 12. Hereinafter, the differences between the above-described embodiment and this modified example will be mainly described. The coil 6 includes coil conductors 61 and 67 and a plurality of coil conductors 62 to 66. As shown in FIG. 12, the coil conductor layers 610 to 670 respectively correspond to the coil conductor 61, the coil conductors 62 to 66, and the coil conductor 67 when viewed from the direction D1.

[0049] When viewed from the direction D1, the coil 6 has a circular shape. The number of turns of the coil 6 is 2.5 turns. The coil conductors 61 and 67 and each of the coil conductors 62 to 66 constitute a part of an annular orbit in the coil 6. The coil conductors 61 and 67 and each of the coil conductors 62 to 66 have, for example, an arc shape. The coil conductors 61 and 67 and each of the coil conductors 62 to 66 have equal thicknesses to each other. The coil conductors 61 and 67 are located at the ends of the coil 6. The coil conductor 61 is located at one end of the coil 6 in the direction D1, and the coil conductor 67 is located at the other end of the coil 6 in the direction D1. The coil conductor 61 is included in the same layer as the connection conductor 51, and the coil conductor 67 is included in the same layer as the connection conductor 52. The plurality of coil conductors 62, 63, 64, 65, and 66 are arranged in sequence along the direction D1. The coil conductor 62 is adjacent to the coil conductor 61 in the direction D1, and the coil conductor 66 is adjacent to the coil conductor 67 in the direction D1.

[0050] The path lengths of the coil conductors 61 to 63 are 1 / 2 turn or more. The path length of the coil conductor 64 is 1 / 2 turn or less. The path lengths of the coil conductors 65 and 67 are 1 / 2 turn or more. The path lengths of the coil conductors 61 and 67 may be equal to each other. The path lengths of the coil conductors 62, 66, 65, and 66 may be equal to each other. The coil conductor 61 has a longer path length than the coil conductor 62. The coil conductor 67 has a longer path length than the coil conductor 66. The coil conductors 61 and 67 have a longer path length than any of the path lengths of the plurality of coil conductors 62 to 66. The coil conductor 64 has the shortest path length among the path lengths of the plurality of coil conductors 62 to 66.

[0051] As shown in FIG. 12, the coil 6 includes connection portions 6a, 6b, 6c, 6d, 6e, and 6f. When viewed from the direction D1, the connection portions 6a, 6b, 6c, 6d, 6e, and 6f are curved. When viewed from the direction D1, the connection portions 6a, 6b, 6c, 6d, 6e, and 6f exhibit, for example, an arc shape. In the connection portion 6a, the coil conductor 61 and the coil conductor 62 overlap and are physically connected. The connection portion 6a includes the entire coil conductor 62. In the connection portion 6b, the adjacent coil conductors 62 and 63 overlap and are physically connected. In the connection portion 6c, the adjacent coil conductors 63 and 64 overlap and are physically connected. In the connection portion 6d, the adjacent coil conductors 64 and 65 overlap and are physically connected. In the connection portion 6e, the adjacent coil conductors 65 and 66 overlap and are physically connected. In the connection part 6f, the coil conductor 66 and the coil conductor 67 overlap and are physically connected. The connection part 6f includes the entire coil conductor 66.

[0052] The connection parts 6a and 6f are defined as the first connection parts, and the connection parts 6b, 6c, 6d, and 6e are defined as a plurality of second connection parts. The areas of the connection parts 6a and 6f may be equal to each other. The areas of the connection parts 6b and 6e may be equal to each other. The areas of the connection parts 6c and 6d may be equal to each other. The area of the connection parts 6c and 6d is the smallest among the areas of the connection parts 6b, 6c, 6d, and 6e. The area of the connection parts 6a and 6f is larger than the area of the connection parts 6c and 6d. The area of the connection parts 6a and 6f is larger than any of the areas of the connection parts 6b, 6c, 6d, and 6e. The path lengths of the connection parts 6a and 6f may be equal to each other. The path lengths of the connection parts 6b and 6e may be equal to each other. The path lengths of the connection parts 6c and 6d may be equal to each other. The path length of the connection parts 6c and 6d is the smallest among the path lengths of the connection parts 6b, 6c, 6d, and 6e. The path length of the connection parts 6a and 6f is larger than the path length of the connection parts 6c and 6d. The path length of the connection parts 6a and 6f is larger than any of the path lengths of the connection parts 6b, 6c, 6d, and 6e.

[0053] As described above, the present invention has been described in detail based on its embodiments. However, the present invention is not limited to the above embodiments. The present invention can be variously modified without departing from its gist. The present invention may be, for example, a combination of the above-described embodiments and modified examples.

[0054] The coil 3 may include only the coil conductor 31 and the coil conductor 32. The coil 3 may include only the coil conductor 37 and the coil conductor 36. In the present embodiment, since the coil 3 includes the coil conductors 31 and 37 and the coil conductors 32 and 36, and two connection parts 3a and 3f are formed, the multilayer coil component 1 can further improve the Q value of the multilayer coil component. The path length may be the minimum length from the end face of the first end to the end face of the second end of the coil conductors 31 and 37 and each of the coil conductors 32 to 36. For example, the path length may be the inner circumference from the end face of the first end to the end face of the second end of the coil conductors 31 and 37 and each of the coil conductors 32 to 36. The connecting portion 3a does not necessarily include the entire coil conductor 32. The connecting portion 3f does not necessarily include the entire coil conductor 36.

[0055] As can be understood from the description of the above-described embodiments and modifications, this specification includes the disclosure of the following aspects. (Appendix 1) A base body, a coil disposed within the base body, an external electrode disposed on the surface of the base body, a connection conductor disposed within the base body and electrically connecting the coil and the external electrode to each other, The coil a first coil conductor located at an end of the coil and included in the same layer as the connection conductor, including a second coil conductor adjacent to the first coil conductor in one direction, and a plurality of coil conductors arranged in the one direction, The first coil conductor has a path length longer than that of the second coil conductor, The first coil conductor and the second coil conductor form a first connection portion that overlaps and is physically connected to each other, Among the plurality of coil conductors, adjacent coil conductors form a plurality of second connection portions that overlap and are physically connected to each other, The area of the first connection portion as viewed from the one direction is larger than the smallest area among the areas of the plurality of second connection portions as viewed from the one direction, A multilayer coil component. (Appendix 2) The area of the first connection portion as viewed from the one direction is larger than any of the areas of the plurality of second connection portions as viewed from the one direction, The multilayer coil component according to Appendix 1. (Appendix 3) A base body, A coil disposed within the element body, an external electrode disposed on the surface of the element body, and a connection conductor disposed within the element body and electrically connecting the coil and the external electrode. The coil includes a first coil conductor located at an end of the coil and included in the same layer as the connection conductor, and a plurality of coil conductors including a second coil conductor adjacent to the first coil conductor in one direction and arranged in the one direction. The first coil conductor has a path length longer than that of the second coil conductor. The first coil conductor and the second coil conductor form a first connection portion that overlaps and is physically connected to each other. Among the plurality of coil conductors, adjacent coil conductors form a plurality of second connection portions that overlap and are physically connected to each other. The first connection portion has a path length longer than the shortest path length among the path lengths of the plurality of second connection portions. A multilayer coil component. (Appendix 4) The path length of the first connection portion is longer than any of the path lengths of the plurality of second connection portions. The multilayer coil component according to Appendix 3. (Appendix 5) The first coil conductor has a path length longer than any of the path lengths of the plurality of coil conductors. The multilayer coil component according to any one of Appendices 1 to 4. (Appendix 6) The first connection portion includes the entire second coil conductor. The multilayer coil component according to any one of Appendices 1 to 5. (Appendix 7) The first connection portion is curved when viewed from the one direction. The multilayer coil component according to any one of Appendices 1 to 6.

Explanation of Reference Numerals

[0056] 1…Stacked coil component, 2…Element body, 3, 6…Coil, 31, 32, 33, 34, 35, 36, 37…Coil conductor, 30…Plurality of coil conductors, 41, 42…External electrode, 51, 52…Connection conductor, 61, 62, 63, 64, 65, 66, 67…Coil conductor, 3a, 3f, 6a, 6f…Connection part, 3b, 3c, 3d, 3e, 6b, 6c, 6d, 6e…Connection part, D1, D2, D3…Direction.

Claims

1. A base body, a coil disposed within the base body, an external electrode disposed on the surface of the base body, and a connection conductor disposed within the base body for electrically connecting the coil and the external electrode to each other, wherein the coil includes a first coil conductor located at an end of the coil and included in the same layer as the connection conductor, and a plurality of coil conductors arranged in the one direction, including a second coil conductor adjacent to the first coil conductor in the one direction, the first coil conductor has a path length longer than that of the second coil conductor, the first coil conductor and the second coil conductor form a first connection portion that overlaps and is physically connected to each other, adjacent coil conductors among the plurality of coil conductors form a plurality of second connection portions that overlap and are physically connected to each other, an area of the first connection portion viewed from the one direction is larger than a smallest area among areas of the plurality of second connection portions viewed from the one direction, a multilayer coil component.

2. The area of the first connection portion viewed from the one direction is larger than any of the areas of the plurality of second connection portions viewed from the one direction, The multilayer coil component according to Claim 1.

3. A base body, a coil disposed within the base body, an external electrode disposed on the surface of the base body, and a connection conductor disposed within the base body for electrically connecting the coil and the external electrode to each other, wherein the coil includes a first coil conductor located at an end of the coil and included in the same layer as the connection conductor, and a plurality of coil conductors arranged in the one direction, including a second coil conductor adjacent to the first coil conductor in the one direction, the first coil conductor has a path length longer than that of the second coil conductor, the first coil conductor and the second coil conductor form a first connection portion that overlaps and is physically connected to each other, adjacent coil conductors among the plurality of coil conductors form a plurality of second connection portions that overlap and are physically connected to each other, the first connection portion has a path length longer than a shortest path length among path lengths of the plurality of second connection portions, a multilayer coil component.

4. The path length of the first connection portion is longer than any of the path lengths of the plurality of second connection portions, The multilayer coil component according to Claim 3.

5. The first coil conductor has a path length longer than any of the path lengths of the plurality of coil conductors, The multilayer coil component according to any one of Claims 1 to 4.

6. The first connection portion includes the entire second coil conductor. The multilayer coil component according to any one of claims 1 to 4.

7. The first connection portion is curved when viewed from the one direction. The multilayer coil component according to any one of claims 1 to 4.

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