Coil device

Abstract

Provided is a coil device in which parasitic capacitance is reduced. The coil device includes: a drum core including a first flange portion, a second flange portion, and a winding core portion; a first terminal portion provided on the first flange portion; a second terminal portion provided on the second flange portion; a first coil wound around a winding core portion first portion of the winding core portion and connected to the first terminal portion and the second terminal portion; and a second coil wound around a second winding core portion of the winding core portion and connected to the second terminal portion and the first terminal portion, in the winding core portion, a first side surface protruding portion and a second side surface protruding portion are formed on a first winding core side surface and a second winding core side surface, the first side surface protruding portion and the second side surface protruding portion being disposed between the first winding core portion and the second winding core portion. The lead-out part of the first coil is connected to the second terminal part after being engaged with the lower end of the first side surface protruding part or the upper end of the first side surface protruding part, and the lead-out part of the second coil is engaged with the first terminal part after being engaged with the upper end of the second side surface protruding part or the lower end of the second side surface protruding part.

Description

Technical Field

[0001] The present invention relates to a coil device that can be used as a DMI or the like, for example. Background Art

[0002] A coil device having two coils on a winding core portion of a core has been disclosed (Patent Document 1). In this coil device, the electromagnetic effects generated by the two coils are balanced by winding the coils around different portions of the same winding core portion.

[0003] However, in such a coil device, an unnecessary parasitic capacitance may be generated at a portion where a lead wire from one coil approaches a winding portion of the other coil, and a reduction in impedance characteristics caused by the generation of the parasitic capacitance becomes a technical problem.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2006-261572 Summary of the invention

[0007] 1. Technical issues to be resolved

[0008] The present invention has been made in view of the above-mentioned actual situation, and an object of the present invention is to provide a coil device capable of preventing the generation of parasitic capacitance.

[0009] (II) Technical solution

[0010] In order to achieve the above object, the coil device of the present invention has:

[0011] a drum core having a first flange portion and a second flange portion and a winding core portion connecting the first flange portion and the second flange portion;

[0012] a plurality of first terminal portions, which are arranged on the first flange portion; a plurality of second terminal portions, which are arranged on the second flange portion;

[0013] A first coil, which is wound multiple turns around a portion of the winding core portion on the side close to the first flange portion, namely, a first portion of the winding core portion, and one end of the first coil is connected to one of the first terminals and the other end of the first coil is connected to one of the second terminals; and

[0014] A second coil is wound with a plurality of turns on a portion of the winding core portion near the second flange portion, i.e., a second portion of the winding core portion, one end of which is connected to one of the second terminal portions, and the other end of which is connected to one of the first terminal portions.

[0015] In the core portion, a first side protrusion and a second side protrusion are formed on the first side surface of the core and the second side surface of the core, wherein the first side surface of the core and the second side surface of the core connect the upper surface of the core and the lower surface of the core, facing opposite directions to each other, and the first side protrusion and the second side protrusion are arranged between the first part of the core portion and the second part of the core portion in the first side surface of the core and the second side surface of the core,

[0016] The lead-out portion of the first coil led out from the first part of the winding core to the second terminal portion is connected to the second terminal portion after being engaged with the lower end of the first side protrusion or the upper end of the first side protrusion, wherein the lower end of the first side protrusion is located at the same position as or higher than the lower surface of the winding core, and the upper end of the first side protrusion is located at the same position as or lower than the upper surface of the winding core.

[0017] The lead-out portion of the second coil led out from the second part of the core portion to the first terminal portion is connected to the first terminal portion after engaging with the upper end of the second side protrusion or the lower end of the second side protrusion, wherein the upper end of the second side protrusion is located at the same position as or lower than the upper surface of the core, and the lower end of the second side protrusion is located at the same position as or higher than the lower surface of the core.

[0018] In such a coil device, the lead-out portion of each coil is connected to the first terminal portion or the second terminal portion on the side opposite to the winding core portion of the wound winding core portion after being engaged with the upper end or the lower end of the first side protrusion portion or the second side protrusion portion. In such a lead-out portion, for example, when the winding direction is a right spiral direction and the terminal positions are parallel, the lead-out portion can be connected to the first terminal portion or the second terminal portion by engaging with the side protrusion portion to avoid the portion directly above the winding portion of the other coils if the side protrusion portion is not present. In addition, for example, when the winding direction is a left spiral direction and the terminal positions are parallel, the lead-out portion can be connected to the first terminal portion or the second terminal portion by engaging with the side protrusion portion to avoid the portion directly above the winding portion of the other coils if the side protrusion portion is not present. In addition, the case where the winding direction is the right spiral direction and the terminal positions are crossed is the same as the case where the winding direction is the left spiral direction and the terminal positions are parallel, and the case where the winding direction is the left spiral direction and the terminal positions are crossed is the same as the case where the winding direction is the right spiral direction and the terminal positions are parallel. As a result, in the coil device, compared with the case where there is no side protrusion, the lead-out portion of each coil can be positioned away from the winding portion of other coils, thereby preventing the generation of parasitic capacitance. In addition, by locating the upper end of the side protrusion at the same position as or lower than the upper surface of the winding core, and the lower end of the side protrusion at the same position as or higher than the lower surface of the winding core, the problem of increased DC resistance (Rdc) caused by the engagement of the coil with the upper end or lower end of the side protrusion can be prevented.

[0019] In addition, for example, a plate core may be further provided. The plate core is disposed above the drum core and connects the flange upper surfaces of the first flange portion and the second flange portion to each other.

[0020] The coil device having such a plate core can form a closed magnetic circuit with a simple structure. In addition, by engaging the lead portion of each coil with the upper end or lower end of the first side protrusion or the second side protrusion, the lead portion does not need to pass through the narrow space between the plate core and the winding portion of other coils, which is also advantageous from the perspective of thinness.

[0021] In addition, for example, the second coil connection first terminal portion, which is one of the plurality of first terminal portions and to which the lead-out portion of the second coil is connected, may also be arranged at a position closer to the second side surface of the winding core than the first side surface of the winding core.

[0022] A first coil connection second terminal portion, which is one of the plurality of second terminal portions and to which the lead portion of the first coil is connected, may be arranged at a position closer to the first side surface of the winding core than to the second side surface of the winding core.

[0023] The first terminal portion or the second terminal portion connected to the lead-out portion of each coil is arranged near the first side surface of the winding core or the second side surface of the winding core formed with the first side protrusion portion or the second side protrusion portion engaged with each lead-out portion, so that the lead-out portion can be connected to the first terminal portion or the second terminal portion, avoiding directly above the winding portion of other coils.

[0024] In addition, for example, the lead portion of the first coil may be connected to the second terminal portion after being engaged with the lower end of the first side protrusion located at a position higher than the lower surface of the winding core.

[0025] The lead portion of the second coil may be connected to the first terminal portion after being engaged with an upper end of the second side surface protrusion located at a position lower than the upper surface of the winding core.

[0026] In a coil device in which the first coil and the second coil are wound in opposite directions and the terminals are arranged in parallel, by adopting such a structure, the stray capacitance can be effectively reduced.

[0027] In addition, for example, the number of turns of the second coil wound around the second portion of the winding core may be the same as the number of turns of the first coil wound around the first portion of the winding core.

[0028] Such a coil device can be suitably used as a noise filter such as a DMI or a common mode coil. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic perspective view of a coil device according to one embodiment of the present invention.

[0030] Figure 2 Observe from the front Figure 1 A front view of the main part of the coil device is shown.

[0031] Figure 3 Observed from above Figure 1 A top view of the main part of the coil device is shown.

[0032] Figure 4 Observed from below Figure 1 A bottom view of the main body portion of the coil device is shown.

[0033] Figure 5 Observed from the rear Figure 1 A rear view of the main body of the coil device is shown.

[0034] Figure 6 This is a schematic perspective view of a drum core included in a coil device according to a modified example.

[0035] Description of reference numerals:

[0036] 10: coil device; 20, 120: drum core; 22, 122: winding core; 23: first part of the winding core; 24: second part of the winding core; 22a, 122a: upper surface of the winding core; 22b, 122b: lower surface of the winding core; 22c, 122c: first side surface of the winding core; 25, 125: first side protrusion; 25a, 125a: upper end; 25b, 125b: lower end end; 22d, 122d: second side of the winding core; 26, 126: second side protrusion; 26a, 126a: upper end; 26b: lower end; 27, 127: first flange; 27a: upper surface of the flange; 27aa: central protrusion; 27ab: first concave portion of the side; 27ac: second concave portion of the side; 27b: lower surface of the flange; 28, 128: second flange; 28 a: upper surface of flange; 28aa: central convex portion; 28ab: first concave portion of side; 28ac: second concave portion of side; 28b: lower surface of flange; 30: first terminal portion; 31: first coil connected to first terminal portion; 31a: wiring portion; 31b: mounting portion; 32: second coil connected to first terminal portion; 32a: wiring portion; 32b: mounting portion; 40: second terminal portion; 41: first coil connected to second terminal portion; 41a: wiring portion; 41b: mounting portion; 42: second coil connected to second terminal portion; 42a: wiring portion; 42b: mounting portion; 50: first coil; 51: lead-out portion; 52: first coil winding portion; 53: base lead-out portion; 60: second coil; 61: lead-out portion; 62: second coil winding portion; 63: base lead-out portion; 70: core. DETAILED DESCRIPTION

[0037] Hereinafter, the coil device of the present disclosure will be described with reference to the embodiments.

[0038] As one embodiment of the coil device of the present disclosure, the overall structure of a differential mode inductor (DMI) having a function as a noise filter is described. However, the coil device of the present disclosure is not limited to a device used as a differential mode inductor (DMI), and coil devices other than DMI, such as a device used as a common mode filter, are also included in the coil device of the present disclosure.

[0039] Figure 1 FIG. 1 is a schematic three-dimensional diagram of a coil device 10 according to an embodiment of the present disclosure. Figure 1 As shown, the coil device 10 has a substantially rectangular parallelepiped shape as a whole, and includes a first coil 50, a second coil 60, a drum core 20 having a winding core portion 22 wound with the first coil 50 and the second coil 60, and a plate core 70. In addition, the coil device 10 includes a plurality of first terminal portions 30 provided on a first flange portion 27 of the drum core 20 and a plurality of second terminal portions 40 provided on a second flange portion 28.

[0040] The outer dimensions of the coil device 10 are, for example, 4.3-4.7 mm in length in the X-axis direction×2.6-3.0 mm in height in the Z-axis direction×3.0-3.4 mm in width in the Y-axis direction, but the dimensions of the coil device 10 are not limited thereto.

[0041] The drum core 20 has a first flange portion 27 and a second flange portion 28 and a winding core portion 22 connecting the first flange portion 27 and the second flange portion 28. The winding core portion 22 extends along the Y axis, the first flange portion 27 is arranged at one end side of the winding core portion 22 (the negative direction side of the Y axis), and the second flange portion 28 is arranged at the other end side of the winding core portion 22 (the positive direction side of the Y axis). That is, the winding core portion 22 connects the mutually opposing surfaces of the first flange portion 27 and the second flange portion 28 to each other. In addition, in the present disclosure, the direction from the first flange portion 27 toward the second flange portion 28 in the winding core portion 22 is sometimes referred to as the positive direction of the Y axis, and the direction toward the opposite direction is referred to as the negative direction. In addition, the direction perpendicular to the mounting surface of the coil device 10 and the direction from the mounting surface toward the winding core portion 22 and the plate core 70 is sometimes referred to as the positive direction or the upper direction of the Z axis, and the direction toward the opposite direction is referred to as the negative direction or the lower direction of the Z axis. The X axis, the Y axis, and the Z axis are perpendicular to each other.

[0042] Figure 2 Observe from the front Figure 1 The front view of the main body of the coil device 10 excluding the plate core 70 is shown. Figure 3 This is a top view of the main body of the coil device 10 as viewed from above. Figure 2 as well as Figure 3 It can be understood that the core portion 22 of the drum core 20 has a substantially rectangular shape, and the YZ cross section is substantially rectangular. The core portion 22 has: a core upper surface 22a facing upward (Z-axis positive direction); a core lower surface 22b facing downward (Z-axis negative direction); and a core first side surface 22c and a core second side surface 22d facing the side (Y-axis direction).

[0043] The first side surface 22c of the core and the second side surface 22d of the core connect the upper surface 22a of the core and the lower surface 22b of the core, and face opposite directions to each other. In addition, in the present disclosure, the direction from the first side surface 22c of the core toward the second side surface 22d of the core is sometimes referred to as the positive direction of the X-axis, and the opposite direction is referred to as the negative direction.

[0044] like Figure 2 as well as Figure 3 As shown in FIG. 2 , the first flange portion 27 and the second flange portion 28 have substantially symmetrical shapes across the winding core portion 22. Figure 1 As shown, the first flange portion 27 and the second flange portion 28 are substantially quadrilateral when viewed from the Y-axis direction, and have a substantially rectangular parallelepiped three-dimensional shape.

[0045] like Figure 3 As shown in the figure, the upper surface 27a of the first flange portion 27, which is the surface facing upward, has a central convex portion 27aa; a side first concave portion 27ab arranged on the negative side of the central convex portion 27aa in the X-axis direction; and a side second concave portion 27ac arranged on the positive side of the central convex portion 27aa in the X-axis direction. When viewed from above, the central convex portion 27aa is arranged on the extension of the winding core portion 22 and is located in the center of the X-axis direction. The central convex portion 27aa is located above the side first concave portion 27ab and the side second concave portion 27ac.

[0046] The upper surface 28a of the second flange 28, which is the surface facing upward, also has, similarly to the first flange 27, a central convex portion 28aa, a side first concave portion 28ab disposed on the negative side of the central convex portion 28aa in the X-axis direction, and a side second concave portion 28ac disposed on the positive side of the central convex portion 28aa in the X-axis direction. When viewed from above, the central convex portion 28aa is disposed on the extension of the winding core 22 and is located in the center of the X-axis direction. The central convex portion 28aa is located above the side first concave portion 28ab and the side second concave portion 28ac.

[0047] like Figure 1 As shown in FIG. 1 , the plate core 70 is disposed above the drum core 20. The plate core 70 connects the flange upper surfaces 27a and 28b of the first flange portion 27 and the second flange portion 28 in the drum core 20. Figure 1 As shown, in the coil device 10 of the embodiment, the core 70 connects the central protrusion 27 aa of the flange upper surface 27 a of the first flange 27 and the central protrusion 28 aa of the flange upper surface 28 a of the second flange 28 .

[0048] like Figure 3 As shown, the plurality of first terminal portions 30 include a first coil connection first terminal portion 31 and a second coil connection first terminal portion 32. The first coil connection first terminal portion 31 and the second coil connection first terminal portion 32 are both provided on the first flange portion 27. However, the first coil connection first terminal portion 31 is arranged at a position closer to the first side surface 22c of the winding core than the second side surface 22d of the winding core, whereas the second coil connection first terminal portion 32 is arranged at a position closer to the second side surface 22d of the winding core than the first side surface 22c of the winding core.

[0049] Figure 5 1 is a rear view of the main body of the coil device 10 as viewed from the back. Figure 2 and as a rear view Figure 5As shown, the first coil connection first terminal portion 31 and the second coil connection first terminal portion 32 have: a connection portion 31a, 32a provided on the flange portion upper surface 27a of the first flange portion 27; a mounting portion 31b, 32b provided on the flange portion lower surface 27b of the first flange portion 27; and a connection portion that connects the connection portion 31a, 32a and the mounting portion 31b, 32b and is arranged on the end surface of the first flange portion 27. Figure 3 As shown, the connection portion 31a of the first coil connected to the first terminal portion 31 is configured in the side first recess 27ab close to the first side surface 22c of the winding core, and the connection portion 32a of the second coil connected to the first terminal portion 32 is configured in the side second recess 27ac close to the second side surface 22d of the winding core.

[0050] like Figure 3 As shown, the plurality of second terminal portions 40 include a first coil connection second terminal portion 41 and a second coil connection second terminal portion 42. The first coil connection second terminal portion 41 and the second coil connection second terminal portion 42 are both provided on the second flange portion 28. However, the first coil connection second terminal portion 41 is arranged at a position closer to the first side surface 22c of the winding core than the second side surface 22d of the winding core, whereas the second coil connection second terminal portion 42 is arranged at a position closer to the second side surface 22d of the winding core than the first side surface 22c of the winding core.

[0051] As the main view Figure 2 and as a rear view Figure 5 As shown, the first coil connection second terminal portion 41 and the second coil connection second terminal portion 42 have: a connection portion 41a, 42a provided on the flange portion upper surface 28a of the second flange portion 28; a mounting portion 41b, 42b provided on the flange portion lower surface 28b of the second flange portion 28; and a connection portion that connects the connection portion 41a, 42a and the mounting portion 41b, 42b and is arranged on the end surface of the second flange portion 28. Figure 3 As shown, the connection portion 41a of the first coil connected to the second terminal portion 41 is configured in the side first recess 28ab close to the first side surface 22c of the winding core, and the connection portion 42a of the second coil connected to the second terminal portion 42 is configured in the side second recess 28ac close to the second side surface 22d of the winding core.

[0052] like Figure 2 As shown, the first coil connection first terminal portion 31 provided on the first flange portion 27 and the first coil connection second terminal portion 41 provided on the second flange portion 28 are arranged approximately symmetrically with respect to the symmetry axis extending in the Z-axis direction at the center of the winding core portion 22. Figure 5As shown, the second coil connecting first terminal portion 32 provided on the first flange portion 27 and the second coil connecting second terminal portion 42 provided on the second flange portion 28 are arranged substantially symmetrically with respect to a symmetry axis extending in the Z-axis direction at the center of the winding core portion 22 .

[0053] like Figure 2 as well as Figure 3 As shown, the coil device 10 includes two coils, a first coil 50 and a second coil 60. The first coil 50 and the second coil 60 are formed of coated electric wires or the like, and the first coil 50 and the second coil 60 are insulated from each other.

[0054] like Figure 2 As shown, one end of the first coil 50 is connected to the first coil connection first terminal portion 31 which is one of the first terminal portions 30, and the other end is connected to the first coil connection second terminal portion 41 which is one of the second terminal portions 40. In addition, the first coil 50 has a first coil winding portion 52 wound with a plurality of turns on a portion of the winding core portion 22 on the side close to the first flange portion 27, that is, the winding core portion first portion 23.

[0055] The first coil 50 has, in addition to the first coil winding portion 52, a lead portion 51 of the first coil 50 that is led out from the winding core first portion 23 to the first coil connection second terminal portion 41, and a base lead portion 53 of the first coil 50 that is led out from the winding core first portion 23 to the first coil connection first terminal portion 31. An end of the base lead portion 53 that is also an end of one side of the first coil 50 is connected to the connection portion 31a of the first coil connection first terminal portion 31. In addition, an end of the lead portion 51 that is also an end of the other side of the first coil 50 is connected to the connection portion 41a of the first coil connection second terminal portion 41.

[0056] like Figure 1 As shown, the connection portion 31a of the first coil connected to the first terminal portion 31 and the connection portion 41a of the first coil connected to the second terminal portion 41 are arranged in the gap between the lower surface of the plate core 70 and the flange upper surface 27a, 28a of the first flange portion 27 or the second flange portion 28.

[0057] like Figure 5 As shown, one end of the second coil 60 is connected to the second coil connection second terminal portion 42 which is one of the second terminal portions 40, and the other end is connected to the second coil connection first terminal portion 32 which is one of the first terminal portions 30. In addition, the second coil 60 has a second coil winding portion 62 wound with a plurality of turns on a portion of the winding core portion 22 on the side close to the second flange portion 28, that is, the winding core portion second portion 24.

[0058] The second coil 60 has, in addition to the second coil winding portion 62, a lead portion 61 of the second coil 60 that is led out from the winding core second portion 24 to the second coil connection first terminal portion 32, and a base lead portion 63 of the second coil 60 that is led out from the winding core second portion 24 to the second coil connection second terminal portion 42. An end of the base lead portion 63, which is also an end of one side of the second coil 60, is connected to the connection portion 42a of the second coil connection second terminal portion 42. In addition, an end of the lead portion 61, which is also an end of the other side of the second coil 60, is connected to the connection portion 32a of the second coil connection first terminal portion 32.

[0059] according to Figure 1 It can be understood that the connection portion 32a of the second coil connected to the first terminal portion 32 and the connection portion 42a of the second coil connected to the second terminal portion 42 are arranged in the gap between the lower surface of the core 70 and the upper surface 27a, 28a of the flange portion of the first flange portion 27 or the second flange portion 28 in the same manner as the connection portions 31a, 41a.

[0060] Figure 4 Observed from below Figure 1 FIG. 1 is a bottom view of the main body of the coil device 10 except the plate core 70. Figure 2~Figure 5 As shown, a first side protrusion 25 is formed on the first side surface 22c of the core 22 and is disposed between the first part 23 of the core and the second part 24 of the core. In addition, a second side protrusion 26 is formed on the second side surface 22d of the core 22 and is disposed between the first part 23 of the core and the second part 24 of the core.

[0061] like Figure 2~Figure 4 As shown, in the first side surface 22c of the core, the first side protrusion 25 protrudes toward the negative direction of the X-axis relative to the surface of the portion constituting the core first portion 23 and the core second portion 24. The upper end 25a of the first side protrusion 25 is located at the same position as or lower than the core upper surface 22a, and the lower end 25b of the first side protrusion 25 is located at the same position as or higher than the core lower surface 22b.

[0062] In addition, if Figure 3~Figure 5 As shown, in the second side surface 22d of the core, the second side protrusion 26 protrudes toward the positive direction of the X-axis relative to the surface of the portion constituting the core first portion 23 and the core second portion 24. The upper end 26a of the second side protrusion 26 is located at the same position as or lower than the core upper surface 22a, and the lower end 26b of the second side protrusion 26 is located at the same position as or higher than the core lower surface 22b.

[0063] like Figure 2 As shown, the lead portion 51 of the first coil 50 led out from the first winding core portion 23 to the first coil connection second terminal portion 41 is connected to the first coil connection second terminal portion 41 after being engaged with the lower end 25b of the first side protrusion 25 after being led out from the first winding core portion 23. Figure 5 As shown, the lead-out portion 61 of the second coil 60 led out from the second portion 24 of the winding core to the second coil connection first terminal portion 32 is engaged with the upper end 26a of the second side protrusion 26 after being led out from the second portion 24 of the winding core and connected to the second coil connection first terminal portion 32.

[0064] according to Figure 2 as well as Figure 3 It can be understood that the first coil winding portion 52 of the first coil 50 is wound around the first portion 23 of the winding core in a right spiral direction (in a right-handed inwardly advancing form). Figure 3 as well as Figure 5 It can be understood that the second coil winding portion 62 of the second coil 60 is wound along the left spiral direction (in the form of left-handed rotation and inward advancement) on the second portion 24 of the winding core. Since the first coil 50 is in the right spiral direction, the lead-out portion 51 of the first coil 50 is connected to the first coil connection second terminal portion 41 after being engaged with the lower end 25b of the first side protrusion 25. In contrast, since the second coil 60 is in the left spiral direction, the lead-out portion 61 of the second coil 60 is connected to the second coil connection first terminal portion 32 after being engaged with the upper end 26a of the second side protrusion 26.

[0065] However, the winding direction of the first coil winding portion 52 of the first coil 50 is not limited to the right spiral direction, and the first coil winding portion 52 of the first coil 50 can also be wound on the first part 23 of the winding core in the left spiral direction. In this case, the lead-out portion 51 of the first coil 50 can be connected to the first coil connection second terminal portion 41 after being engaged with the upper end 25a of the first side protrusion 25 after being led out from the first part 23 of the winding core. Regardless of whether the first coil 50 is right-handed or left-handed, it is preferred that the first coil connection first terminal portion 31 and the first coil connection second terminal portion 41 to which the end of the first coil 50 is connected are arranged on the same side relative to the X-axis direction, that is, the side close to the first side surface 22c of the winding core.

[0066] In the coil device 10, the lower end 25b of the first side protrusion 25 is located at a position higher than the lower surface 22b of the winding core (see Figure 2). Therefore, the lead-out portion 51 of the first coil 50 is connected to the first coil connecting second terminal portion 41 after being engaged with the lower end 25b of the first side protrusion 25 located at a position higher than the lower surface 22b of the winding core. However, the lower end 25b of the first side protrusion 25 is not limited to being located at a position higher than the lower surface 22b of the winding core, and may also be Figure 6 As shown in the modified drum core 120, the lower end 125b of the first side protrusion 125 is at the same height as the core lower surface 122b. The upper end 125a of the first side protrusion 125 can be at the same height as the core upper surface 122a.

[0067] In addition, the winding direction of the second coil winding portion 62 of the second coil 60 is not limited to the left spiral direction, and the second coil winding portion 62 of the second coil 60 can also be wound on the second part 24 of the winding core along the right spiral direction. In this case, the lead-out portion 61 of the second coil 60 can be connected to the second coil connection first terminal portion 32 after being engaged with the lower end 26b of the second side protrusion 26 after being led out from the second part 24 of the winding core. Regardless of whether the second coil 60 is right-handed or left-handed, it is preferred that the second coil connection first terminal portion 32 and the second coil connection second terminal portion 42 to which the end of the first coil 50 is connected are arranged on the same side relative to the X-axis direction, that is, the side close to the second side surface 22d of the winding core.

[0068] In the coil device 10, the upper end 25a of the second side protrusion 26 is located at a position lower than the core upper surface 22a (see Figure 5 ). Therefore, the lead-out portion 61 of the second coil 60 is connected to the second coil connection first terminal portion 32 after being engaged with the upper end 26a of the second side protrusion 26 located at a position lower than the core upper surface 22a. However, the upper end 26a of the second side protrusion 26 is not limited to being located at a position lower than the core upper surface 22a, but may also be located at a position lower than the core upper surface 22a. Figure 6 As shown in the drum core 120 of the modified example, the upper end 126a of the second side protrusion 126 is at the same height as the core upper surface 122a. The lower end of the second side protrusion 126 can also be at the same height as the core lower surface 122b.

[0069] In the coil device 10, the number of turns of the second coil 60 wound on the second part 24 of the winding core is the same as the number of turns of the first coil 50 wound on the first part 23 of the winding core. Such a coil device 10 can be suitable for use as a noise filter such as a DMI and a common mode coil. However, the number of turns of the first coil 50 and the second coil 60 may be different from each other. In addition, the same number of turns of the first coil 50 and the second coil 60 refers to the case where the difference in the number of turns of the first coil 50 and the second coil 60 is less than 1 turn.

[0070] like Figures 1 to 5 As shown, the coil device 10 is connected to the second terminal portion 41 or the first terminal portion 32 on the opposite side of the first portion 23 or the second portion 24 of the winding core 22 after the lead-out portion 51, 61 of each coil 50, 60 is engaged with the lower end 25b of the first side protrusion 25 or the upper end 26a of the second side protrusion 26. Thus, with respect to the lead-out portion 51 of the first coil 50 whose winding direction is the right spiral direction, it is possible to make it as if there is no first side protrusion 25. Figure 3 As shown by the double dotted line, the lead-out portion passes through the portion directly above the second coil winding portion 62 of the second coil 60, and by engaging with the lower end 25b of the first side protrusion 25, avoids the portion directly above the second coil winding portion 62 and is connected to the first coil connecting second terminal portion 41.

[0071] Thus, by preventing the lead-out portion 51 of the first coil 50 from passing directly above the second coil winding portion 62 of the second coil 60, the generation of parasitic capacitance in the coil device 10 can be reduced. This is because there is a plate core 70 on the upper side of the second coil winding portion 62, and if the lead-out portion 51 passes through such a narrow space, the lead-out portion 51 has to be close to the second coil winding portion 62. On the other hand, if Figure 3 As shown, with respect to the side (the negative direction side of the X-axis) of the second coil winding portion 62, there is more space in terms of the configuration space of the first coil connecting the first terminal portion 31 and the first coil connecting the second terminal portion 41. Therefore, by passing the lead portion 51 of the first coil 50 through the side of the second coil winding portion 62, the distance between the lead portion 51 and the second coil winding portion 62 can be increased, thereby reducing the generation of parasitic capacitance.

[0072] like Figure 3 As shown, from the perspective of reducing the generation of parasitic capacitance, it is preferred that when the main body of the coil device 10 is observed from above, the lead-out portion 51 of the first coil 50 does not overlap with the second coil winding portion 62, and the lead-out portion 61 of the second coil 60 does not overlap with the first coil winding portion 52.

[0073] In addition, the lead-out portion 61 of the second coil 60 whose winding direction is the left helical direction can be made to be as if there is no second side protrusion 26. Figure 5 As shown by the double dotted line 65, the lead-out portion passes through the side portion of the first coil winding portion 52 of the first coil 50, engages with the upper end 26a of the second side protrusion 26 to avoid passing through the vicinity of the first coil winding portion 52 as much as possible, and is connected to the second coil connecting first terminal portion 32.

[0074] Thus, by avoiding the lead-out portion 61 of the second coil 60 from passing near the side of the first coil winding portion 52 of the first coil 50 as much as possible, the generation of parasitic capacitance in the coil device 10 can be reduced. However, since the space on the side of the first coil winding portion 52 is more abundant than the space above, even if the second side protrusion 26 is not present, the problem is less than that of the case where the first side protrusion 25 is not present. For example, the height difference between the upper end 26a of the second side protrusion 26 and the upper surface 22a of the winding core can be less than 1. Figure 5 The case shown is large.

[0075] In addition, by positioning the lower end 25b of the first side protrusion 25 at the same position as or higher than the core lower surface 22b, and positioning the upper end 26a of the second side protrusion 26 at the same position as or lower than the core upper surface 22a, it is possible to prevent the problem of a DC resistance (Rdc) increasing due to the engagement of the first coil 50 and the second coil 60 with the upper end or the lower end of the side protrusions 25 and 26. This is because, assuming that the lower end 25b of the first side protrusion 25 is lower than the core lower surface 22b, and the upper end 26a of the second side protrusion 26 is higher than the core upper surface 22a, a portion of the first coil 50 and the second coil 60 is separated from the core 22 near the engagement position with these protrusions, and the portion of the first coil 50 and the second coil 60 that contributes less to the performance of the coil device 10 increases.

[0076] In addition, the coil device 10 can form a closed magnetic circuit with a simple structure by having a plate core 70, and because the lead-out portions 51, 61 do not pass between the plate core 70 and the first coil winding portion 52 or the second coil winding portion 62, the gap between the plate core 70 and the first coil winding portion 52 and the second coil winding portion 62 can be narrowed and thinned.

[0077] In addition, if Figure 3As shown, the lead-out portion 51 of the first coil 50 is engaged with the first side protrusion 25, which is formed on the first side surface 22c of the winding core on the side of the first coil connected to the second terminal portion 41 connected to the end of the lead-out portion 51. On the other hand, the lead-out portion 61 of the second coil 60 is engaged with the second side protrusion 26, which is formed on the second side surface 22d of the winding core on the side of the second coil connected to the first terminal portion 32 connected to the end of the lead-out portion 61. That is, the first coil connected to the second terminal portion 41 or the second coil connected to the first terminal portion 32 connected to the lead-out portions 51 and 61 and the first side protrusion 25 or the second side protrusion 26 engaged with the lead-out portions 51 and 61 are arranged on the same side with respect to the winding center axis as the reference. Thus, it is possible to avoid that each lead-out portion 51 and 61 passes directly above the winding portion of other coils different from the coils of the lead-out portions 51 and 61, and effectively prevent the generation of parasitic capacitance.

[0078] (Method of Manufacturing Coil Device 10)

[0079] Next, a method for manufacturing the coil device 10 according to one embodiment of the present invention will be described in detail.

[0080] In manufacturing the coil device 10, first, the drum core 20, the plate core 70, the conductors (covered conductors) that become the first coil 50 and the second coil 60, the plurality of first terminal portions 30, and the plurality of second terminal portions 40 are prepared. The drum core 20 and the plate core 70 are respectively composed of different magnetic parts, but preferably, they are made of the same material, but they may also be composed of different magnetic materials.

[0081] As the magnetic material, for example, a magnetic material with relatively high magnetic permeability, such as Ni-Zn ferrite, Mn-Zn ferrite or metal magnetic body, etc. can be exemplified, and the powder of these magnetic materials is molded and sintered to produce the drum core and the plate core 70. In the drum core 20, the winding core portion 22, the first side protrusion portion 25, the second side protrusion portion 26, the first flange portion 27 and the second flange portion 28 are integrally formed.

[0082] Next, the first coil connection first terminal portion 31 and the second coil connection first terminal portion 32 constituting the plurality of first terminal portions 30 are mounted on the first flange portion 27. In addition, the first coil connection second terminal portion 41 and the second coil connection second terminal portion 42 constituting the plurality of second terminal portions 40 are mounted on the second flange portion 28. At this time, a non-conductive adhesive may be interposed between the terminal portion and the flange portion for bonding.

[0083] The first terminal portion 30 and the second terminal portion 40 are formed by bending a strip-shaped metal plate mainly composed of copper alloy such as phosphor bronze and brass, phosphorus, copper, tin, iron, zinc, etc. Figure 1 In addition, in each terminal portion 31, 32, 41, 42, a known plating layer such as nickel or tin may be formed on the surface of the side opposite to the side facing the flange portion. In addition, the terminal is not limited to a metal plate, and a metal paste may be applied to the flange portion and sintered to form it.

[0084] Then, if Figure 1 As shown, the first coil winding portion 52 of the first coil 50 is formed by winding the conductive wire as the raw material of the first coil 50 with a predetermined number of turns around the first winding core portion 23. In addition, with respect to one end of the first coil 50, the end of the base lead portion 53 led out from the first coil winding portion 52 is fixed to the connection portion 31a of the first coil connection first terminal portion 31. In addition, with respect to the other end of the first coil 50, a part of the lead portion 51 is engaged with the lower end 25b of the first side protrusion 25, and the end of the lead portion 51 is fixed to the connection portion 41a of the first coil connection second terminal portion 41.

[0085] As for the second coil 60, similarly to the first coil 50, the conductive wire as the raw material of the second coil 60 is wound around the second winding core portion 24 with a predetermined number of turns, thereby forming the second coil winding portion 62 of the second coil 60. In addition, as for one end of the second coil 60, the end of the base lead portion 63 led out from the second coil winding portion 62 is fixed to the connection portion 42a of the second coil connection second terminal portion 42. In addition, as for the other end of the second coil 60, a part of the lead portion 61 is engaged with the upper end 26a of the second side protrusion 26, and the end of the lead portion 61 is fixed to the connection portion 32a of the second coil connection first terminal portion 32.

[0086] When forming the first coil 50 and the second coil 60, the winding of the wire can be performed by a known method such as winding with an automatic winding device or manual winding. In addition, the formation of the first coil winding portion 52 and the second coil winding portion 62 can be performed before the end of the wire is fixed to the terminal, or after either end of the wire is fixed to the terminal, and the formation order is not particularly limited.

[0087] The method for connecting the ends of the first coil 50 and the second coil 60 to the connection portions 31a, 32a, 41a, 42a of the terminals is not particularly limited, and for example, laser welding, thermocompression bonding, soldering, etc. may be used.

[0088] Finally, the plate core 70 is fixed to the drum core 20 on which the first coil 50 and the second coil 60 are formed, thereby obtaining the coil device 10 .

[0089] As described above, the coil device 10 of the present disclosure is connected to the first coil connection second terminal portion 41 or the second coil connection first terminal portion 32 on the side opposite to the first portion 23 or the second portion 24 of the wound winding core portion 22 after the lead portions 51, 61 of each coil 50, 60 are engaged with the lower end 25b of the first side protrusion 25 or the upper end 26a of the second side protrusion 26. By engaging the lead portions 51, 61 with the lower end 25b of the first side protrusion 25 or the upper end 26a of the second side protrusion 26, the distance between the lead portions 51, 61 and the winding portions 52, 62 of the other coils can be increased compared to the case where these first side protrusions 25 and the second side protrusions 26 are not present, thereby reducing the parasitic capacitance generated in the coil device 10. Since the coil device 10 can reduce the generation of parasitic capacitance, the reduction of impedance characteristics associated with the generation of parasitic capacitance can also be appropriately prevented.

[0090] The coil device of the present disclosure is described above by enumerating the embodiments, but the coil device of the present disclosure is not limited to the coil device 10 shown in the embodiments. The technical scope of the coil device of the present disclosure certainly includes coil devices of various other embodiments and modified examples. For example, the coil device 10 may also have coils other than the first coil 50 and the second coil 60, and the first terminal portion 30 and the second terminal portion 40 may also include three or more terminal portions, respectively.

[0091] In addition, the coil device 10 may be a device without the plate core 70. In addition, the shape of the drum core 20 is not limited to Figure 1~Figure 5 Shape shown. Figure 6 1 is a perspective view of a drum core 120 according to a modified example. Figure 1 The drum core 20 shown in the above-mentioned figures similarly has a first flange portion 127, a second flange portion 128, a winding core portion 122, etc. A first side protrusion 125 is formed on the first side surface 122c of the winding core of the winding core portion 122, and a second side protrusion 126 is formed on the second side surface 122d of the winding core of the winding core portion 122.

[0092] The upper ends 125a, 126a and the lower ends 125b of the first side protrusion 125 and the second side protrusion 126 of the drum core 120 are at the same height as the core upper surface 122a and the core lower surface 122b, respectively. Figure 6 The drum core 120 shown replaces Figure 1 The coil device of the drum core 20 shown in FIG. 1 also has the same effect as the coil device 10 of the first embodiment. However, from the perspective of suppressing the DC resistance of the coil device, it is more preferable to Figure 1As shown in the drum core 20, the upper ends 25a and 26a of the first side protrusion 25 and the second side protrusion 26 are located lower than the core upper surface 22a, and the lower ends 25b and 26b are located higher than the core lower surface 22b.

Claims

1. A coil device, comprising: a drum core having a first flange portion and a second flange portion and a winding core portion connecting the first flange portion and the second flange portion; a plurality of first terminal portions, which are arranged on the first flange portion; a plurality of second terminal portions, which are arranged on the second flange portion; A first coil, which is wound multiple turns around a portion of the winding core portion on one side close to the first flange portion, namely, a first portion of the winding core portion, and one end of the first coil is connected to one of the first terminals and the other end of the first coil is connected to one of the second terminals; as well as A second coil is wound with a plurality of turns on a portion of the winding core portion near the second flange portion, i.e., a second portion of the winding core portion, one end of which is connected to one of the second terminal portions, and the other end of which is connected to one of the first terminal portions. In the core portion, a first side protrusion and a second side protrusion are formed on the first side surface of the core and the second side surface of the core, wherein the first side surface of the core and the second side surface of the core connect the upper surface of the core and the lower surface of the core, facing opposite directions to each other, and the first side protrusion and the second side protrusion are arranged between the first part of the core portion and the second part of the core portion in the first side surface of the core and the second side surface of the core, The lead-out portion of the first coil led out from the first part of the winding core to the second terminal portion is connected to the second terminal portion after being engaged with the lower end of the first side protrusion or the upper end of the first side protrusion, wherein the lower end of the first side protrusion is located at the same position as or higher than the lower surface of the winding core, and the upper end of the first side protrusion is located at the same position as or lower than the upper surface of the winding core. The lead-out portion of the second coil led out from the second part of the core portion to the first terminal portion is connected to the first terminal portion after engaging with the upper end of the second side protrusion or the lower end of the second side protrusion, wherein the upper end of the second side protrusion is located at the same position as or lower than the upper surface of the core, and the lower end of the second side protrusion is located at the same position as or higher than the lower surface of the core.

2. The coil device according to claim 1, characterized in that A core plate is further provided. The core plate is disposed above the drum core and connects the flange upper surfaces of the first flange portion and the second flange portion to each other.

3. The coil device according to claim 1, characterized in that A second coil connection first terminal portion, which is one of the plurality of first terminals and to which the lead-out portion of the second coil is connected, is arranged at a position closer to the second side surface of the winding core than to the first side surface of the winding core. A first coil connection second terminal portion, which is one of the plurality of second terminal portions and to which the lead portion of the first coil is connected, is arranged at a position closer to the first side surface of the winding core than to the second side surface of the winding core.

4. The coil device according to claim 1, characterized in that The lead portion of the first coil is connected to the second terminal portion after being engaged with the lower end of the first side protrusion located at a position higher than the lower surface of the winding core. The lead portion of the second coil is connected to the first terminal portion after being engaged with the upper end of the second side surface protrusion located at a position lower than the upper surface of the winding core.

5. The coil device according to claim 1, characterized in that The number of turns of the second coil wound around the second portion of the winding core is the same as the number of turns of the first coil wound around the first portion of the winding core.

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