Coil device

Abstract

To provide a coil device with a high attachment stability of a terminal fitting to a flange part.SOLUTION: A coil device 1 has: a winding part 11 to which a wire 10 is wound; a core 20 that has a winding core part 21 to which the winding part 11 is provided and a flange part 22a formed on an end part in an axial direction of the winding core part 21; and a terminal tool 30a that is attached to the flange part 22a. The terminal tool 30a has: a main body part 31 that is arranged on an outer end surface 224 of the flange part 22a; a mounting part 32 that is continued to the main body part 31, and is bent toward a mounting surface 221 from the outer end surface 224; and a wire connection part 33 that is continued to the main body part 31, and is bent toward a side surface 225 from the outer end surface 224. The mounting part 32 has a plurality of mounting pieces 321 and 322 that are separated via a gap 320. The main body part 31 is adhered to the outer end surface 224 by an adhesive agent.SELECTED DRAWING: Figure 1A

Description

[Technical field]

[0001] The present invention relates to a coil device having a terminal device. [Background technology]

[0002] As shown in Patent Document 1, a coil device in which a terminal tool is provided on the flange of a core has been conventionally known. In the coil device of Patent Document 1, the terminal tool has a fitting part that fits into the flange. The fitting part has a mounting part arranged on the lower surface (mounting surface) of the flange, a connecting part arranged on the upper surface (the surface opposite to the mounting surface) of the flange, and a main body part arranged on the outer end surface of the flange. The mounting part is connected to a land pattern of a mounting board, and the connecting part is connected to a lead-out part of the coil. The lower surface and upper surface of the flange are sandwiched between the mounting part and the connecting part, and the terminal tool can be fixed to the flange by the fitting part.

[0003] However, in the coil device of Patent Document 1, when the terminal device is attached to the flange, the fitting portion may rotate around the axis of the main body, and the fitting portion may be fixed to the flange in a direction different from the desired direction. In this case, when mounting the coil device on a board, it may be difficult to position the mounting portion at a desired position on the land pattern of the board. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2005-56934 A Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a coil device in which a terminal device can be attached to a flange portion with high stability. [Means for solving the problem]

[0006] In order to achieve the above object, a coil device according to the present invention comprises: a winding portion around which the wire is wound; a core having a winding core portion on which the winding portion is provided and a flange portion formed on an axial end portion of the winding core portion; A terminal device attached to the flange portion, The terminal device has a main body portion disposed on an outer end surface of the flange portion, a mounting portion continuing with the main body portion and bending from the outer end surface toward the mounting surface of the flange portion, and a connecting wire portion continuing with the main body portion and bending from the outer end surface toward a side surface of the flange portion, the mounting portion has a plurality of mounting pieces spaced apart with gaps therebetween, The body portion is adhered to the outer end surface by an adhesive.

[0007] In the coil device according to the present invention, the terminal tool has a main body portion arranged on the outer end surface of the flange portion, and a connecting wire portion that is continuous with the main body portion and bent from the outer end surface of the flange portion toward the side surface. Therefore, the main body portion and the connecting wire portion function together as a stopper (rotation stopper), making it difficult for the terminal tool to rotate (pivot) in a plane parallel to the mounting surface. This allows the terminal tool to be fixed to the flange portion in a desired orientation, and the attachment stability of the terminal tool to the flange portion can be improved. In addition, the main body portion is bonded to the outer end surface by an adhesive. Therefore, the attachment stability of the terminal tool to the flange portion is improved. In addition, the positional deviation of the terminal tool is suppressed, and the terminal tool can be effectively prevented from rotating (pivoting) in a plane parallel to the mounting surface.

[0008] The terminal device also has a mounting section that is continuous with the main body and bends from the outer end surface of the flange toward the mounting surface. The mounting section has a plurality of mounting pieces that are spaced apart via gaps. Therefore, the area of ​​the mounting section is reduced according to the area of ​​the gap. This reduces the area of ​​the land pattern on the mounting board, and the stray capacitance of the land pattern can be reduced. In addition, when the coil device is mounted on the mounting board by solder, for example, a solder fillet can be formed over a wide area from the mounting pieces to the main body.

[0009] The wire may have a lead-out portion drawn out from the winding portion, and the connection portion may have a connection piece to which the lead-out portion is connected and a welding piece branching off from the connection piece and capable of being bent relative to the connection piece, and the welding piece may be welded while sandwiching the lead-out portion. By sandwiching the lead-out portion between the welding pieces, the lead-out portion can be fixed at a desired position on the connection portion. This makes it easier to weld the lead-out portion and prevents variation in the welding position of the lead-out portion.

[0010] The connecting portion may have a temporary crimping piece that branches off from the connecting piece and can be bent relative to the connecting piece, and the temporary crimping piece may be closer to the winding portion than the welding piece. In this case, after the pull-out portion is temporarily fixed by the temporary crimping piece, the pull-out portion can be sandwiched by the welding pieces and the welding pieces can be welded together with the pull-out portion. This makes it easier to weld the pull-out portion and further improves the accuracy of the welding position of the pull-out portion.

[0011] The wire may have a lead-out portion drawn out from the winding portion, and the connection portion may be laser welded together with the lead-out portion. In this case, the connection portion is integrated with the lead-out portion, and direct current resistance can be reduced from the connection portion to the lead-out portion.

[0012] The flange may have a side cutout formed on the side surface and accommodating at least a part of the connection wire portion, the side cutout extending toward the mounting surface. In this case, the connection wire portion is less likely to protrude outside the flange when viewed from the opposite side to the mounting surface. This makes it possible to reduce the size of the coil device and prevent breakage of the lead-out portion.

[0013] The flange portion has a first flange portion formed at one axial end of the winding core portion and a second flange portion formed at the other axial end of the winding core portion, the terminal device has a first terminal device attached to the first flange portion and a second terminal device attached to the second flange portion, the connecting wire portion has a first connecting wire portion provided on the first terminal device and a second connecting wire portion provided on the second terminal device, the side cutout portion has a first side cutout portion formed on a side surface of the first flange portion and accommodating at least a portion of the first connecting wire portion, and a second side cutout portion formed on a side surface of the second flange portion and accommodating at least a portion of the second connecting wire portion, and when viewed in the axial direction of the winding core portion, the first side cutout portion and the second side cutout portion may be located on the same side in a direction perpendicular to the axial direction. In this case, since the first connection part and the second connection part are located on the same side in a direction perpendicular to the axial direction of the winding core part, welding can be performed on the same side, which makes it easy to weld the pull-out part and the connection part.

[0014] In a direction perpendicular to the mounting surface, the depth of the side cutout portion may be greater than half the height of the flange portion. In this case, the arrangement space for the connecting wire portion is increased, improving the degree of freedom in arranging the connecting wire portion. Therefore, it is easier to draw the lead-out portion to a desired position of the connecting wire portion.

[0015] The flange portion may have a recess formed on the mounting surface, and at least a portion of the recess may be located inside the gap. In this case, the mounting surface is recessed between the mounting pieces (i.e., in the gap) so as to move away from the multiple mounting pieces. Therefore, for example, when the multiple mounting pieces are connected to a mounting board by solder, the solder is less likely to adhere to the mounting surface through the gap in the mounting portion. This makes it possible to prevent damage to the core.

[0016] At least one of the mounting pieces may be bonded to the mounting surface by an adhesive. In this case, the attachment stability of the terminal device to the flange is further improved. In addition, the positional deviation of the terminal device is suppressed, and the terminal device can be effectively prevented from rotating (pivoting) in a plane parallel to the mounting surface.

[0017] The terminal device may have an extended main body portion disposed on the outer end surface and extending from the main body portion toward the opposite side to the mounting portion. In this case, the adhesive area between the terminal device and the outer end surface of the flange portion increases according to the area of ​​the extended main body portion. Therefore, the attachment stability of the terminal device to the flange portion is further improved.

[0018] The coil device may further include a plate-shaped core, and the plate-shaped core may be attached to the mounting-facing surface of the flange portion opposite to the mounting surface. By attaching the plate-shaped core to the mounting-facing surface, the inductance characteristics of the coil device are improved. In addition, unlike the conventional technology, the present invention does not sandwich the mounting surface and the mounting-facing surface with terminal devices, but instead adheres the main body to the outer end surface of the flange portion. Therefore, it is not necessary to cut the mounting-facing surface and the plate-shaped core to prevent interference between the terminal device and the plate-shaped core. This increases the contact area between the mounting-facing surface and the plate-shaped core, improving the inductance characteristics of the coil device. In addition, the bonding strength between the mounting-facing surface and the plate-shaped core is increased. [Brief description of the drawings]

[0019] [Figure 1A] FIG. 1A is a perspective view of a coil device according to a first embodiment of the present invention. [Figure 1B] FIG. 1B is a side view of the coil device shown in FIG. 1A as viewed from the Y-axis direction. [Figure 1C] FIG. 1C is a side view of the coil device shown in FIG. 1A as viewed from the X-axis direction. [Figure 1D] FIG. 1D is a plan view of the coil device shown in FIG. 1A. [Figure 1E] FIG. 1E is a bottom view of the coil arrangement shown in FIG. 1A. [Figure 1F] FIG. 1F is a bottom view showing a modification of the coil device shown in FIG. 1A. [Diagram 2] FIG. 2 is a perspective view of the core shown in FIG. 1A. [Diagram 3] FIG. 3 is a perspective view of the terminal device shown in FIG. 1A. [Figure 4] FIG. 4 is a perspective view of a coil device according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the contents shown in the drawings are merely schematic and illustrative for understanding the present invention, and the appearance and dimensional ratios may differ from the actual product. In addition, the present invention is not limited to the following embodiment.

[0021] First embodiment A coil device 1 according to a first embodiment of the present invention shown in Fig. 1A functions as, for example, an inductor, and is mounted on the power supplies of various electrical devices. The coil device 1 has a wire 10, a core 20, and terminal devices 30a and 30b. In addition to these components, the coil device 1 has a plate-shaped core 40. However, the plate-shaped core 40 is not essential.

[0022] The wire 10 has a winding portion 11 in which the wire 10 is wound in a spiral shape, and drawn-out portions 12a and 12b drawn out from the winding portion 11. The wire 10 is an insulating-coated wire in which a conductive core wire such as a round wire is covered with an insulating coating. More specifically, the wire 10 is a known winding wire such as AIW (polyamideimide copper wire), UEW (polyurethane copper wire), PEW (polyester copper wire), etc. The material constituting the wire 10 is not particularly limited, but is, for example, copper, copper alloy, silver, or nickel. The diameter of the wire 10 is not particularly limited, but is, for example, 10 to 300 μm. In addition, the wire 10 does not need to have an insulating coating.

[0023] Lead-out portion 12a is drawn from one end of winding portion 11 in the winding axis direction toward terminal device 30a and is connected to terminal device 30a (connection portion 33). Lead-out portion 12b is drawn from the other end of winding portion 11 in the winding axis direction toward terminal device 30b and is connected to terminal device 30b (connection portion 33).

[0024] 2, the core 20 is a drum core and has a winding core portion 21 and flange portions 22a and 22b. The material constituting the core 20 is not particularly limited, but may be, for example, a magnetic metal or ferrite (Ni-Zn ferrite, Mn-Zn ferrite, etc.). The core 20 may be formed of a composite material containing a magnetic material and a resin.

[0025] The cross-sectional shape of the winding core 21 is a rectangle, but may be another polygon (for example, a hexagon or an octagon), a circle, an ellipse, etc. As shown in Fig. 1A, the winding core 21 is provided with a winding portion 11.

[0026] 2, flange portion 22a is formed at one axial end of winding core portion 21, and flange portion 22b is formed at the other axial end of winding core portion 21. The shape of flange portion 22a is the same as the shape of flange portion 22b, but may be different.

[0027] The flange portion 22a has a mounting surface 221, a mounting facing surface 222, an inner end surface 223, an outer end surface 224, a first side surface 225, and a second side surface 226. Similarly, the flange portion 22b has a mounting surface 221, a mounting facing surface 222, an inner end surface 223, an outer end surface 224, a first side surface 225, and a second side surface 226.

[0028] The mounting surface 221 and the opposing mounting surface 222 face each other, the inner end surface 223 and the outer end surface 224 face each other, and the first side surface 225 and the second side surface 226 face each other. In the following, the axis along the direction in which the inner end surface 223 and the outer end surface 224 face each other is referred to as the X-axis. The axis along the direction in which the first side surface 225 and the second side surface 226 face each other is referred to as the Y-axis. In addition, the axis along the direction in which the mounting surface 221 and the opposing mounting surface 222 face each other is referred to as the Z-axis. The X-axis, the Y-axis, and the Z-axis are mutually orthogonal. The X-axis is an axis parallel to the axial direction of the winding core portion 21.

[0029] For each of the X-axis, Y-axis, and Z-axis, the direction toward the center of the core 20 is defined as the "inner side," and the direction away from the center of the core 20 is defined as the "outer side." Additionally, the positive side of the Z-axis is defined as the "upper side," and the negative side of the Z-axis is defined as the "lower side." However, the upper side in the Z-axis direction does not necessarily coincide with the upper side in the vertical direction. Additionally, the lower side in the Z-axis direction does not necessarily coincide with the lower side in the vertical direction.

[0030] The mounting surface 221 is a surface that is placed on a mounting board (not shown). A recess 24 is formed in the mounting surface 221. The recess 24 extends along the X-axis from one end to the other end of the mounting surface 221 in the X-axis direction. The inner wall of the recess 24 is an inclined surface, but may be a vertical surface. The recess 24 is located at the center of the mounting surface 221 in the Y-axis direction. The position of the recess 24 corresponds to the position of a gap 320 (FIG. 1A) of a terminal device 30a or 30b described later.

[0031] The mounting surface 222 is a surface on which the plate core 40 (FIG. 1A) is disposed. As shown in FIG. 1B, the plate core 40 is disposed on the mounting surface 222 of the flange portion 22a and the mounting surface 222 of the flange portion 22b. The mounting surface 222 is a flat surface. However, the shape of the mounting surface 222 may be appropriately changed depending on the shape of the contact surface 41 of the plate core 40.

[0032] The inner end surface 223 is a surface to which an axial end portion of the winding core portion 21 is connected. The shape of the inner end surface 223 is the same as the shape of the outer end surface 224. As shown in Fig. 1A, the terminal device 30a or 30b is disposed on the mounting surface 221, the outer end surface 224, and the first side surface 225.

[0033] As shown in FIG. 2, the first side surface 225 has a side cutout 23 formed therein. The first side surface 225 is cut out inward in the Y-axis direction at the side cutout 23. The side cutout 23 extends along the Z-axis toward the mounting surface 221. As shown in FIG. 1C, the upper end of the side cutout 23 is located at the center of the first side surface 225. The lower end of the side cutout 23 is located on the mounting surface 221. The depth D of the side cutout 23 in the Z-axis direction is ½ or less of the height H of the flange 22a (first side surface 225) in the Z-axis direction. Therefore, the area of ​​the first side surface 225 at the side cutout 23 is ½ or less of the area of ​​the entire first side surface 225.

[0034] 2, the side cutout portion 23 of the flange portion 22a and the side cutout portion 23 of the flange portion 22b are located on the same side in the Y axis direction (the positive Y axis direction side) as viewed in the X axis direction. However, the side cutout portion 23 of the flange portion 22a and the side cutout portion 23 of the flange portion 22b may be located on different sides in the Y axis direction as viewed in the X axis direction.

[0035] As shown in Fig. 3, the terminal devices 30a and 30b each have a main body portion 31, a mounting portion 32, and a wire connection portion 33. The terminal devices 30a and 30b each further have a main body extension portion 34. However, the main body extension portion 34 is not essential. The shape of the terminal device 30a is mirror symmetrical to the shape of the terminal device 30b.

[0036] The terminal fittings 30a and 30b are made of a conductor such as a metal. The material constituting the terminal fittings 30a and 30b is not particularly limited, but may be, for example, copper, copper alloy, silver, or nickel. A plating film may be formed on the surface of the terminal fittings 30a and 30b. The plating film may be a single layer or may be a multi-layer. The plating film is not particularly limited, but may be, for example, Cu plating, Ni plating, Sn plating, Ni-Sn plating, Cu-Ni-Sn plating, Ni-Au plating, or Au plating. The thickness of the terminal fittings 30a and 30b is not particularly limited, but may be, for example, 50 to 300 μm.

[0037] 1A, the terminal device 30a is attached to the flange portion 22a, and the terminal device 30b is attached to the flange portion 22b. The main body portion 31 has a shape that is long horizontally in the Y-axis direction. The main body portion 31 is disposed on the outer end surface 224 of the flange portion 22a or 22b. More specifically, the main body portion 31 is disposed below the center of the outer end surface 224 in the Z-axis direction (on the mounting surface 221 side).

[0038] As shown in Fig. 3, the mounting portion 32 is continuous with the main body portion 31 and is bent in an L-shape. The mounting portion 32 has mounting pieces 321 and 322. In this embodiment, the number of mounting pieces is two, but it may be three or more. The mounting pieces 321 and 322 are connected to a mounting board (not shown), for example, by solder, a conductive adhesive, or the like. The main body portion 31 may be formed with a fillet of solder, a conductive adhesive, or the like.

[0039] The mounting piece 321 and the mounting piece 322 are spaced apart in the Y-axis direction by a gap 320. The gap 320 is formed between the mounting piece 321 and the mounting piece 322 from one end to the other end in the extension direction of the mounting pieces 321 and 322.

[0040] As shown in FIG. 1A and FIG. 1B, the mounting portion 32 (mounting pieces 321 and 322) is bent (curved) from the outer end surface 224 toward the mounting surface 221. As shown in FIG. 1C, a part of the mounting piece 321 is disposed on the outer end surface 224, and a part of the mounting piece 322 is disposed on the outer end surface 224. Also, as shown in FIG. 1B, a part of the mounting piece 321 is disposed on the mounting surface 221. Although detailed illustration is omitted, a part of the mounting piece 322 is disposed on the mounting surface 221. The mounting piece 321 extends along the Z axis on the outer end surface 224. On the mounting surface 221, the mounting piece 321 extends along the X axis from one end (the end on the outer end surface 224 side) of the mounting surface 221 in the X axis direction to the other side (the inner end surface 223 side). The same applies to the mounting piece 322.

[0041] The mounting piece 321 has a bent portion 323. The bent portion 323 is located between a portion of the mounting piece 321 that is arranged parallel to the outer end surface 224 (a base end portion located on the base end side of the bent portion 323) and a portion of the mounting piece 321 that is arranged parallel to the mounting surface 221 (a tip end portion located on the tip side of the bent portion 323). As shown in FIG. 1B, the bent portion 323 is located at the intersection of the outer end surface 224 and the mounting surface 221. The bent portion 323 is bent (curved) from the outer end surface 224 toward the mounting surface 221 so as to be perpendicular to each other.

[0042] 3, the mounting piece 322 has a bent portion 324. As shown in FIGS. 1C and 1E, the bent portion 324 is located between a portion of the mounting piece 322 that is arranged parallel to the outer end surface 224 (a base end portion located on the base end side of the bent portion 324) and a portion that is arranged parallel to the mounting surface 221 (a tip end portion located on the tip side of the bent portion 324). The bent portion 324 is located at an intersection between the outer end surface 224 and the mounting surface 221. The bent portion 324 is bent (curved) from the outer end surface 224 toward the mounting surface 221 so as to be perpendicular to the outer end surface 224.

[0043] At least a part of the recess 24 formed on the mounting surface 221 (in this embodiment, the entire recess 24) is located inside the gap 320, that is, between the mounting piece 321 and the mounting piece 322. In other words, the mounting pieces 321 and 322 are arranged outside the recess 24 in the Y-axis direction so as not to block the recess 24. The mounting surface 221 is recessed between the mounting piece 321 and the mounting piece 322 (that is, the gap 320) so as to move away from the mounting pieces 321 and 322. Therefore, for example, when the mounting pieces 321 and 322 are connected to a land pattern of a mounting board by solder, the solder is less likely to adhere to the mounting surface 221 through the gap 320. This makes it possible to prevent damage to the core 20.

[0044] The mounting portion 32 and the main body portion 31 are located on one side (second side surface 226 side) of the center in the Y-axis direction of the mounting surface 221. On the other hand, the connecting wire portion 33 is located on the other side (first side surface 225 side) of the center in the Y-axis direction of the mounting surface 221. Therefore, the balance of the coil device 1 is improved between the one side and the other side of the center in the Y-axis direction of the mounting surface 221, and the mounting stability of the coil device 1 can be improved.

[0045] The mounting piece 321 is located more inward than one end (end on the first side surface 225 side) of the mounting surface 221 in the Y axis direction. Therefore, a part of the mounting surface 221 is exposed from the mounting section 32 on one side in the Y axis direction. The mounting piece 322 is located more inward than the other end (end on the second side surface 226 side) of the mounting surface 221 in the Y axis direction. Therefore, a part of the mounting surface 221 is exposed from the mounting section 32 on the other side in the Y axis direction.

[0046] 3, the connecting wire portion 33 is continuous with the main body portion 31, and is bent (curved) in an L shape. The connecting wire portion 33 has a connecting wire piece 330, a temporary crimping piece 332, and a welding piece 333. As shown in FIG. 1A, the connecting wire portion 33 (connecting wire piece 330) is bent (curved) from the outer end surface 224 toward the first side surface 225.

[0047] 1A, a portion of the connecting wire piece 330 is disposed on the outer end surface 224, and a portion of the connecting wire piece 330 is disposed on the first side surface 225. The connecting wire piece 330 extends along the Y-axis at the outer end surface 224. The connecting wire piece 330 extends along the X-axis at the first side surface 225, from one end of the first side surface 225 in the X-axis direction (the end on the outer end surface 224 side) to the other side (the inner end surface 223 side).

[0048] The connecting piece 330 has a bent portion 331. The bent portion 331 is located between a portion of the connecting piece 330 that is arranged parallel to the outer end surface 224 (a base end portion located on the base end side of the bent portion 331) and a portion of the connecting piece 330 that is arranged parallel to the first side surface 225 (a tip end portion located on the tip side of the bent portion 331). The bent portion 331 is located at the intersection of the outer end surface 224 and the first side surface 225, and is bent (curved) from the outer end surface 224 toward the first side surface 225.

[0049] As shown in FIG. 1E, a gap is formed between the connecting piece 330 and the first side surface 225, and the connecting piece 330 does not abut against the first side surface 225. For example, by making the position of the gap 320 between the mounting piece 321 and the mounting piece 322 correspond to the position of the recess 24 of the mounting surface 221, a gap of a predetermined width can be formed between the connecting piece 330 and the first side surface 225. As shown in FIG. 1F, the connecting piece 330 may abut against the first side surface 225. The abutment of the connecting piece 330 against the first side surface 225 can prevent the bending portion 331 from being deformed. Although the main body portion 31 abuts against the outer end surface 224 in FIG. 1E and FIG. 1F, the main body portion 31 may not abut against the outer end surface 224.

[0050] 1B and 1C, at least a part of the connecting wire portion 33 is accommodated in the side cutout portion 23. More specifically, a part of the connecting wire piece 330 (a part from the bent portion 331 to the tip side) is accommodated in the side cutout portion 23. A part of the crimping piece 332 and a part of the welding piece 333 are also accommodated in the side cutout portion 23. In this embodiment, the connecting wire portion 33 of the terminal device 30a and the connecting wire portion 33 of the terminal device 30b are both arranged on the same side in the Y-axis direction, so that welding can be performed on the same side. Therefore, welding of the drawing portion 12a or 12b and the connecting wire portion 33 is easy.

[0051] As shown in FIG. 1C, when viewed from the X-axis direction, the connecting wire piece 330 does not protrude outward in the Y-axis direction from the end of one side (first side surface 225 side) of the mounting surface 222 in the Y-axis direction. Therefore, when viewed from the opposite side to the mounting surface 221, the connecting wire piece 330 is hidden by the mounting surface 222 at the position of the side cutout portion 23. Also, as shown in FIG. 1D, when viewed from the opposite side to the mounting surface 221, the connecting wire piece 330 is hidden by the plate-shaped core 40 at the position of the side cutout portion 23. In this way, since the connecting wire piece 330 does not protrude outward from the outer edge of the plate-shaped core 40, the coil device 1 can be made smaller. Also, disconnection of the lead-out portion 12a connected to the connecting wire piece 330 can be prevented.

[0052] As shown in FIG. 3, the welding piece 333 branches off from the connecting piece 330 and is configured to be bent relative to the connecting piece 330. In FIG. 3, the state of the welding piece 333 of the terminal device 30b before bending is shown by a solid line, and the state after bending is shown by a two-dot chain line. The welding piece 333 is bent upward (toward the mounting facing surface 222 in FIG. 2) from the lower end of the connecting piece 330. The tip of the welding piece 333 is formed wide, but the shape of the welding piece 333 is not particularly limited. In the bent state of the welding piece 333, the tip of the welding piece 333 (the portion on the tip side from the bending position) faces the connecting piece 330.

[0053] 1B, the weld piece 333 of the terminal device 30a is welded while sandwiching the drawn-out portion 12a. The drawn-out portion 12a is located between the connecting wire piece 330 and the weld piece 333, and is sandwiched between the connecting wire piece 330 and the weld piece 333. The weld piece 333 of the terminal device 30b is welded while sandwiching the drawn-out portion 12b. The drawn-out portion 12b is located between the connecting wire piece 330 and the weld piece 333, and is sandwiched between the connecting wire piece 330 and the weld piece 333.

[0054] The drawn-out portion 12a is laser-welded together with the connecting portion 33. Since the drawn-out portion 12a melts together with the welding piece 333 and / or the connecting piece 330, a welding ball 50 is formed in the connecting portion 33. The drawn-out portion 12b is laser-welded together with the connecting portion 33. Since the drawn-out portion 12b melts together with the welding piece 333 and / or the connecting piece 330, a welding ball 50 is formed in the connecting portion 33. As an example, the welding ball 50 is formed at the tip of the welding piece 333. In this way, the welding ball 50 integrates the connecting portion 33 with the drawn-out portion 12a or 12b, and therefore the direct current resistance can be reduced from the connecting portion 33 to the drawn-out portion 12a or 12b.

[0055] Furthermore, by clamping the drawn-out portion 12a or 12b with the welding pieces 333, the drawn-out portion 12a or 12b can be fixed at a desired position of the connection portion 33. This makes it easier to weld the drawn-out portion 12a or 12b and prevents variation in the welding position of the drawn-out portion 12a or 12b.

[0056] In addition, the lead-out portions 12a and 12b may be connected to the connection portion 33 (connection piece 330 and / or weld piece 333) by, for example, solder, conductive adhesive, thermocompression bonding, ultrasonic bonding, resistance brazing, ultraviolet curing resin bonding, etc.

[0057] As shown in Fig. 3, the temporary crimping piece 332 branches off from the connecting wire piece 330 and is configured to be bendable relative to the connecting wire piece 330. In Fig. 3, the state of the temporary crimping piece 332 of the terminal device 30b before bending is shown by a solid line, and the state after bending is shown by a two-dot chain line. The temporary crimping piece 332 is bent downward (toward the mounting surface 221 in Fig. 2) from the upper end of the connecting wire piece 330. In the bent state of the temporary crimping piece 332, the tip portion of the temporary crimping piece 332 (the portion on the tip side from the bending position) faces the connecting wire piece 330.

[0058] 1B, the temporary crimping piece 332 of the terminal device 30a sandwiches the lead-out portion 12a. The lead-out portion 12a is located between the connecting wire piece 330 and the temporary crimping piece 332, and is sandwiched between the connecting wire piece 330 and the temporary crimping piece 332. The temporary crimping piece 332 of the terminal device 30b sandwiches the lead-out portion 12b. The lead-out portion 12b is located between the connecting wire piece 330 and the temporary crimping piece 332, and is sandwiched between the connecting wire piece 330 and the temporary crimping piece 332.

[0059] The temporary crimping piece 332 and the welded piece 333 are disposed at different positions along the X-axis. The temporary crimping piece 332 is closer to the winding portion 11 than the welded piece 333. More specifically, the welded piece 333 is located on the outer end surface 224 side, whereas the temporary crimping piece 332 is located on the inner end surface 223 side. In this embodiment, the drawn-out portion 12a can be sandwiched by the temporary crimping piece 332 before being sandwiched by the welded piece 333. Then, after the drawn-out portion 12a is temporarily fixed by the temporary crimping piece 332, the drawn-out portion 12a can be sandwiched by the welded piece 333 and the welded piece 333 can be welded together with the drawn-out portion 12a. This facilitates welding of the drawn-out portion 12a and improves the accuracy of the welding position of the drawn-out portion 12a.

[0060] The size of the welding piece 333 is larger than the size of the temporary crimping piece 332. This ensures a contact area between the drawn-out portion 12a and the welding piece 333, and allows the drawn-out portion 12a to be stably sandwiched by the welding piece 333. Furthermore, when the drawn-out portion 12a is welded together with the welding piece 333 and / or the connecting piece 330, a melting range is ensured, making it easier to ensure conduction between the drawn-out portion 12a and the connecting portion 33.

[0061] 1E, a portion of the welding piece 333 is accommodated in the side cutout 23, and a remaining portion of the welding piece 333 is exposed from the side cutout 23. However, the entirety of the welding piece 333 may be accommodated in the side cutout 23. Also, a portion of the temporary crimping piece 332 is accommodated in the side cutout 23, and a remaining portion of the temporary crimping piece 332 is exposed from the side cutout 23. However, the entirety of the temporary crimping piece 332 may be accommodated in the side cutout 23.

[0062] 1B and 1C, at least a portion of the welding ball 50 is housed in the side cutout 23. In this embodiment, a portion of the welding ball 50 is housed in the side cutout 23, and the remaining portion of the welding ball 50 is exposed from the side cutout 23. However, the entire welding ball 50 may be housed in the side cutout 23. This reduces the dimension of the coil device 1 in the Y-axis direction, and the coil device 1 can be made more compact.

[0063] As shown in FIG. 1D, at least a part of the welding ball 50 is hidden by the plate-shaped core 40 when viewed from the opposite side to the mounting surface 221 (FIG. 2). As shown by the two-dot chain line in FIG. 1D, the welding ball 50 may be formed further inside the welding piece 333 in the X-axis direction. For example, 30% or more of the area of ​​the welding ball 50 may be hidden by the plate-shaped core 40 when viewed from the Z-axis direction. Although detailed illustration is omitted, when the plate-shaped core 40 is not disposed on the core 20 (FIG. 2), at least a part of the welding ball 50 is hidden by the flange 22a or 22b (mounting facing surface 222) when viewed from the opposite side to the mounting surface 221. In this embodiment, a part of the welding ball 50 is hidden by the plate-shaped core 40 and the flange 22a, but the entire welding ball 50 may be hidden by the plate-shaped core 40 and the flange 22a. Similarly, a portion of the weld ball 50 is hidden by the plate core 40 and the flange portion 22b, but the entire weld ball 50 may be hidden by the plate core 40 and the flange portion 22b.

[0064] This makes it possible to prevent at least a part of the welding beads 50 from being exposed outside the outer edges of the flanges 22a and 22b when viewed from the opposite side to the mounting surface 221. As a result, the dimensions of the coil device 1 are reduced, and the coil device 1 can be made more compact.

[0065] 1B, the height position of the upper end portion of the temporary crimping piece 332 (the bent portion of the temporary crimping piece 332) is substantially equal to the height position of the lower end portion of the winding core portion 21. In this embodiment, the height position of the upper end portion of the temporary crimping piece 332 is spaced downward from the height position of the lower end portion of the winding core portion 21 by a distance L. However, the distance L may be five times or less the diameter of the wire 10, or may be two times or less the diameter of the wire 10. The height position of the upper end portion of the temporary crimping piece 332 may be equal to the height position of the lower end portion of the winding core portion 21. In other words, L may be 0.

[0066] This allows the pull-out portion 12a to be pulled straight along the X-axis from the lower end of the winding core 21 toward the upper end of the temporary crimping piece 332. Also, the pull-out portion 12a can be crimped at the upper end of the temporary crimping piece 332 (near the bent portion of the temporary crimping piece 332), preventing the pull-out portion 12a from shifting in position or falling off. Also, the pull-out portion 12a can be pulled from the lower end of the winding core 21 to the upper end of the temporary crimping piece 332 without bending it excessively, preventing breakage of the wire 10.

[0067] 1C, the extended main body portion 34 is disposed on the outer end surface 224, and extends from the main body portion 31 toward the opposite side to the mounting surface 221. The extended main body portion 34 extends to the center of the outer end surface 224 in the Z-axis direction. However, the length of the extended main body portion 34 in the Z-axis direction is not particularly limited, and the extended main body portion 34 may extend further upward than the center of the outer end surface 224 in the Z-axis direction.

[0068] In this embodiment, the adhesion area between the terminal device 30a and the outer end surface 224 can be increased according to the area of ​​the expanded main body portion 34. Therefore, the attachment stability of the terminal device 30a to the outer end surface 224 is improved.

[0069] As shown in FIG. 1C, the main body portion 31 is adhered to the outer end surface 224 by the adhesive 60. In FIG. 1C, the adhesive 60 is indicated by a two-dot chain line, but the range of the adhesive 60 is not limited to the area indicated by the two-dot chain line. The adhesive 60 is attached to at least a part of the main body portion 31. The adhesive 60 may be attached to a part of the main body portion 31, or may be attached to the entire main body portion 31. The adhesive 60 may also be attached to a plurality of locations (for example, two locations) of the main body portion 31. For example, the adhesive 60 may be attached to a first region on one side of the main body portion 31 in the Y-axis direction and a second region (a region different from the first region) on the other side of the main body portion 31 in the Y-axis direction. The adhesive 60 may also be attached to at least a part of the extended main body portion 34.

[0070] As shown in Fig. 1E, the mounting piece 321 is adhered to the mounting surface 221 by the adhesive 60. Furthermore, the mounting piece 322 is adhered to the mounting surface 221 by the adhesive 60. In Fig. 1E, the adhesive 60 is indicated by a two-dot chain line, but the range of the adhesive 60 is not limited to the area indicated by the two-dot chain line. In this embodiment, both the mounting pieces 321 and 322 are adhered to the mounting surface 221 by the adhesive 60, but only one of the mounting pieces 321 and 322 may be adhered to the mounting surface 221 by the adhesive 60.

[0071] As shown in Fig. 1A, the plate core 40 has a rectangular parallelepiped shape (flat shape). The plate core 40 may be made of the same material as the core 20, or may be made of a material different from that of the core 20. The plate core 40 is adhered to the mounting surface 222 (Fig. 2) of the core 20 by, for example, an adhesive. By attaching the plate core 40 to the mounting surface 222, the inductance characteristics of the coil device 1 are improved.

[0072] Next, a method for manufacturing the coil device 1 will be described. First, the wire 10, the core 20, the terminal fittings 30a and 30b, and the plate-shaped core 40 shown in FIG. 1A are prepared. The length of the core 20 in the X-axis direction is not particularly limited, but is, for example, 1 to 6 mm. The length of the core 20 in the Y-axis direction is not particularly limited, but is, for example, 0.5 to 4 mm. The length of the core 20 in the Z-axis direction is not particularly limited, but is, for example, 0.5 to 3 mm.

[0073] Next, the terminal device 30a is adhered to the flange portion 22a, and the terminal device 30b is adhered to the flange portion 22b. More specifically, as shown in Fig. 1C and Fig. 1E, the main body portion 31 is adhered to the outer end surface 224 by an adhesive 60. Furthermore, as necessary, the mounting pieces 321 and 322 are adhered to the mounting surface 221. Note that after the winding portion 11 is formed on the winding core portion 21, the terminal device 30a may be adhered to the flange portion 22a, and the terminal device 30b may be adhered to the flange portion 22b.

[0074] Next, the wire 10 is wound around the winding core 21 to form the winding portion 11 on the winding core 21. Next, as shown in FIG. 1B , the wire 10 is drawn out from one end of the winding portion 11 in the X-axis direction toward the connection portion 33 of the terminal device 30a. Then, the temporary crimping piece 332 is bent, and the wire 10 is sandwiched by the temporary crimping piece 332. Thereafter, the wire 10 is further drawn out toward the outer end surface 224 of the flange portion 22a, and the welding piece 333 is bent, and the wire 10 is sandwiched by the welding piece 333.

[0075] Moreover, the wire 10 is drawn out from the other end in the X-axis direction of the winding portion 11 toward the connection portion 33 of the terminal device 30b. Then, the temporary crimping piece 332 is bent, and the wire 10 is sandwiched by the temporary crimping piece 332. Thereafter, the wire 10 is further drawn out toward the outer end surface 224 of the flange portion 22b, and the welding piece 333 is bent, and the wire 10 is sandwiched by the welding piece 333.

[0076] Next, the lead-out portion 12a is fused together with the weld piece 333 and / or the connecting wire piece 330 of the terminal device 30a by, for example, laser welding. As a result, a weld ball 50 is formed in the connecting wire portion 33, and the lead-out portion 12a is integrated with the connecting wire portion 33. In addition, the lead-out portion 12b is fused together with the weld piece 333 and / or the connecting wire piece 330 of the terminal device 30b. As a result, a weld ball 50 is formed in the connecting wire portion 33, and the lead-out portion 12b is integrated with the connecting wire portion 33.

[0077] Next, the plate core 40 is adhered to the mounting facing surfaces 222 of the flange portions 22a and 22b by an adhesive. In this manner, the coil device 1 shown in FIG. 1A can be manufactured.

[0078] 1A, in this embodiment, the terminal device 30a has a main body 31 disposed on the outer end surface 224, and a connecting wire portion 33 that is continuous with the main body 31 and bends from the outer end surface 224 toward the first side surface 225. Therefore, the main body 31 and the connecting wire portion 33 function together as a stopper (rotation stopper), making it difficult for the terminal device 30a to rotate (pivot) in a plane parallel to the mounting surface 221. As a result, the terminal device 30a is fixed to the flange portion 22a in a desired orientation, and the attachment stability of the terminal device 30a to the flange portion 22a can be improved.

[0079] 1C, the main body 31 is bonded to the outer end surface 224 by the adhesive 60. This improves the attachment stability of the terminal device 30a to the flange portion 22a. Furthermore, the positional deviation of the terminal device 30a is suppressed, and the terminal device 30a can be effectively prevented from rotating (pivoting) in a plane parallel to the mounting surface 221.

[0080] 1A, the terminal device 30a has a mounting portion 32 that is continuous with the main body portion 31 and bent from the outer end surface 224 toward the mounting surface 221. The mounting portion 32 has mounting pieces 321 and 322 that are spaced apart via a gap 320. Therefore, the area of ​​the mounting portion 32 is reduced according to the area of ​​the gap 320. This reduces the area of ​​the land pattern on the mounting board, and the stray capacitance of the land pattern can be reduced. In addition, when the coil device 1 is mounted on the mounting board by solder, for example, a solder fillet can be formed over a wide range from the mounting pieces 321 and 322 to the main body portion 31.

[0081] In addition, in this embodiment, unlike the conventional technology, the mounting surface 221 and the mounting facing surface 222 are not sandwiched by the terminal tool 30a, and the main body 31 is bonded to the outer end surface 224. Therefore, it is not necessary to cut the mounting facing surface 222 and the plate core 40 to prevent interference between the terminal tool 30a and the plate core 40. This increases the contact area between the mounting facing surface 222 and the plate core 40, improving the inductance characteristics of the coil device 1. In addition, the bonding strength between the mounting facing surface 222 and the plate core 40 is increased.

[0082] 1E, the mounting pieces 321 and 322 are adhered to the mounting surface 221 by the adhesive 60. This further improves the attachment stability of the terminal device 30a to the flange portion 22a. Moreover, the positional deviation of the terminal device 30a is suppressed, and the terminal device 30a can be effectively prevented from rotating (pivoting) in a plane parallel to the mounting surface 221.

[0083] Second embodiment The coil device 1A of the second embodiment shown in Fig. 4 has a similar configuration to the coil device 1 of the first embodiment, except for the following points. The same reference numerals are used to designate parts that overlap with the coil device 1 of the first embodiment, and detailed descriptions thereof will be omitted.

[0084] The coil device 1A includes a core 20A having a flange portion 22aA and a terminal device 30aA. In the flange portion 22a of the first embodiment, the side cutout portion 23 is formed on a first side surface 225, whereas in the flange portion 22aA of the present embodiment, the side cutout portion 23 is formed on a second side surface 226.

[0085] In addition, in the terminal device 30a of the first embodiment, the connecting wire portion 33 is adjacent to the mounting piece 321, whereas in the terminal device 30aA of the present embodiment, the connecting wire portion 33 is adjacent to the mounting piece 322. The connecting wire portion 33 (connecting wire piece 330) is continuous with the main body portion 31, and is bent (curved) from the outer end face 224 toward the second side surface 226.

[0086] In this embodiment, the same effect as in the first embodiment can be obtained. In addition, in this embodiment, the side cutout portion 23 of the flange portion 22aA and the side cutout portion 23 of the flange portion 22b are located on different sides in the Y axis direction as viewed from the X axis direction. Also, the connection portion 33 of the terminal device 30aA and the connection portion 33 of the terminal device 30b are located on different sides in the Y axis direction as viewed from the X axis direction. Therefore, the balance of the coil device 1A is improved in the Y axis direction, and the mounting stability of the coil device 1A to the mounting board is improved.

[0087] The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present invention.

[0088] In each of the above embodiments, the coil device 1 is applied to an inductor, but the coil device 1 may be applied to other electronic components (for example, a transformer).

[0089] In each of the above embodiments, the plate core 40 may be omitted from the coil device 1 shown in FIG. 1A.

[0090] 1E, the mounting pieces 321 and 322 are adhered to the mounting surface 221 by the adhesive 60. However, the mounting pieces 321 and 322 do not have to be adhered to the mounting surface 221 by the adhesive 60.

[0091] 1C, the depth D of the side cutout 23 in the Z-axis direction is equal to or less than ½ of the height H of the flange 22a (first side surface 225) in the Z-axis direction. However, the depth D of the side cutout 23 in the Z-axis direction may be greater than ½ of the height H of the flange 22a in the Z-axis direction. In this case, the arrangement space for the connecting wire portion 33 is increased, improving the degree of freedom in arranging the connecting wire portion 33. Therefore, it becomes easier to draw out the lead-out portion 12a to a desired position of the connecting wire portion 33.

[0092] As shown in FIG. 1E, in each of the above embodiments, the entire recess 24 is located inside the gap 320, but a portion of the recess 24 may be located inside the gap 320. [Explanation of symbols]

[0093] 1,1A…Coil device 10…Wire 11...Winding section 12a, 12b…Drawer part 20,20A…Core 21…Coil 22a, 22b, 22aA…Trim part 221...Mounting surface 222…Mounting surface 223…Inner end surface 224...Outer end surface 225…1st side 226…Second side 23…Side cutout 24…Recess 30a,30b,30aA…terminal fitting 31…Main body 32…Mounting section 320…Gap 321, 322…Mounting piece 323,324…Bend 33...Connection section 330...Connection piece 331…Bend 332...Temporary rivet piece 333…Welding piece 34…Extended main body 40…Plate core 41...Abutment surface 50…Welding ball 60…Adhesive

Claims

1. a winding portion around which the wire is wound; a core having a winding core portion on which the winding portion is provided and a flange portion formed on an axial end portion of the winding core portion; A terminal device attached to the flange portion, The terminal device has a main body portion disposed on an outer end surface of the flange portion, a mounting portion continuing with the main body portion and bending from the outer end surface toward the mounting surface of the flange portion, and a connecting wire portion continuing with the main body portion and bending from the outer end surface toward a side surface of the flange portion, the mounting portion has a plurality of mounting pieces spaced apart with gaps therebetween, The coil device wherein the main body is adhered to the outer end surface by an adhesive.

2. The wire has a lead-out portion led out from the winding portion, the connecting wire portion includes a connecting wire piece to which the lead-out portion is connected, and a welding piece branched from the connecting wire piece and bendable relative to the connecting wire piece, The coil device according to claim 1 , wherein the weld pieces are welded while sandwiching the lead portion.

3. The connecting wire portion has a temporary crimping piece that branches off from the connecting wire piece and can be bent relative to the connecting wire piece, The coil device according to claim 2 , wherein the temporary crimping piece is closer to the winding portion than the welded piece is.

4. The wire has a lead-out portion led out from the winding portion, 4. The coil device according to claim 1, wherein the connection portion is laser welded to the lead-out portion.

5. the flange portion has a side cutout portion formed on the side surface and accommodating at least a portion of the connection portion, The coil device according to any one of claims 1 to 3, wherein the side cutout portion extends toward the mounting surface.

6. the flange portion includes a first flange portion formed at one axial end of the winding core portion and a second flange portion formed at the other axial end of the winding core portion, The terminal device includes a first terminal device attached to the first flange portion and a second terminal device attached to the second flange portion, the connecting wire portion includes a first connecting wire portion provided on the first terminal device and a second connecting wire portion provided on the second terminal device, the side cutout portion includes a first side cutout portion formed on a side surface of the first flange portion and accommodating at least a portion of the first connecting wire portion, and a second side cutout portion formed on a side surface of the second flange portion and accommodating at least a portion of the second connecting wire portion, The coil device according to claim 5 , wherein, as viewed in the axial direction of the winding core portion, the first side cutout portion and the second side cutout portion are located on the same side in a direction perpendicular to the axial direction.

7. The coil device according to claim 5 , wherein a depth of the side cutout portion in a direction perpendicular to the mounting surface is greater than half a height of the flange portion.

8. The flange portion has a recess formed on the mounting surface, The coil device according to any one of claims 1 to 3, wherein at least a portion of the recess is located inside the gap.

9. 4. The coil device according to claim 1, wherein at least one of the plurality of mounting pieces is adhered to the mounting surface by an adhesive.

10. The coil device according to any one of claims 1 to 3, wherein the terminal device is disposed on the outer end surface and has an extended main body portion extending from the main body portion toward an opposite side to the mounting portion.

11. Further comprising a plate-shaped core, 4. The coil device according to claim 1, wherein the plate-shaped core is attached to a mounting-facing surface of the flange portion opposite the mounting surface.

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