Coil device

Abstract

The invention provides a coil device which can effectively prevent poor insulation and disconnection of a lead part of a lead wire and is excellent in reliability. A coil device is provided with: a core; a winding part of the wire; and a base plate part on which a terminal is mounted, the terminal being connected to a lead part of the wire led out from the winding part. A core (2) is provided on a first surface of one side of the base plate portion, a wiring portion of a terminal is disposed on a second surface of the other side opposite to the first surface, and a base-side passage is formed in the base plate portion, the base-side passage allowing a lead portion of a lead wire from a winding portion to pass therethrough and guide the lead wire to the wiring portion.

Description

Technical Field

[0001] The present invention relates to a coil device used in various electronic devices. Background Art

[0002] A coil device is known, for example, as shown in Patent Document 1. In this coil device, the end (lead portion) of the helically wound wire is prevented from being located on the base. To this end, a protrusion is provided on the side of the base so that the coil end passes from below toward the terminal.

[0003] However, in the coil device constructed in this way, in order to connect the wire outside the side surface of the base plate portion, the lead portion of the wire abuts against the outer peripheral edge of the base plate portion, and the insulation coating of the lead portion of the wire is easily damaged, and the lead portion of the wire may be poorly insulated or broken.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2010-182733 Summary of the invention

[0007] 1. Technical issues to be resolved

[0008] The present invention has been made in view of the above-mentioned current situation, and an object of the present invention is to provide a coil device which can effectively prevent insulation failure and wire breakage of a lead wire portion of a conducting wire and has excellent reliability.

[0009] (II) Technical solution

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

[0011] a core having a winding core portion;

[0012] a winding portion of the conductive wire, which is spirally arranged around the winding core portion; and

[0013] a base plate portion on which a terminal is mounted, the terminal being connected to a lead portion of the wire led out from the winding portion,

[0014] The core having the winding core portion is provided on one first surface of the base plate portion.

[0015] A connection portion of the terminal is arranged on the other second surface of the base plate portion located on the side opposite to the first surface.

[0016] The base plate portion has a base-side passage formed therein, the base-side passage allowing the lead portion of the conductive wire from the winding portion to pass therethrough and guide the lead portion toward the connecting portion.

[0017] In the coil device of one aspect of the present invention, since a base side passage is formed in the base plate portion, and the base side passage allows the lead portion of the wire from the winding portion to pass through and guide it to the connection portion, the lead portion of the wire becomes less likely to abut against the outer peripheral edge of the base plate portion. Therefore, the insulation coating of the lead portion of the wire is less likely to be damaged, and poor insulation and disconnection of the lead portion of the wire can be effectively prevented, thereby improving the reliability of the coil device.

[0018] Preferably, the base side passage formed in the base plate portion is a cutout-shaped recess or through hole penetrating the first surface and the second surface. With such a configuration, when the lead portion of the wire passes through the base plate portion and is guided through the cutout-shaped recess or through hole, the lead portion of the wire becomes less likely to abut against the outer peripheral edge of the base plate portion.

[0019] Preferably, the inner peripheral edge of the base side passage extends to the vicinity of the winding core. With such a configuration, when the lead portion of the wire is guided from the winding portion of the wire arranged around the winding core to the connection portion located on the second surface of the base plate, the lead portion of the wire is less likely to abut against the outer peripheral edge of the base plate.

[0020] The core may also have a flange portion magnetically connected to the winding core portion. Preferably, the flange portion is arranged on the base plate portion and has a core-side passage connected to the base-side passage. With such a configuration, the lead portion of the wire can be easily guided from the winding portion of the wire arranged on the winding core portion to the connection portion located on the second surface of the base plate portion through the core-side passage and the base-side passage in sequence.

[0021] Therefore, the lead wire portion of the conductor becomes less likely to abut against the outer peripheral edge of the base plate portion, and also becomes less likely to abut against the outer peripheral edge of the flange portion of the core. As a result, the insulation coating of the lead wire portion of the conductor becomes less likely to be damaged, and poor insulation and disconnection of the lead wire portion of the conductor can be further effectively prevented, and the reliability of the coil device is further improved.

[0022] The base plate portion may also have a convex portion, which surrounds at least a portion of the core including the flange portion in a manner protruding from the first surface of the base plate portion. The convex portion can position the core relative to the base plate portion and can improve the insulation between the core arranged on the first surface and the connection portion of the terminal arranged on the second surface.

[0023] The core side passage may also include at least one pair of core side passages. Preferably, one of the pair of core side passages and the other are located on opposite sides of each other around the winding core portion. By configuring in this way, it is possible to implement a method of using the pair of core side passages such as passing the lead portion of the wire constituting the coil on the primary side through one of the pair of core side passages and passing the lead portion of the wire constituting the coil on the secondary side through the other, and it is easy to make the terminals to which the lead portions of the wires that require high insulation are respectively connected be located on opposite sides of each other around the winding core portion.

[0024] The coil device may also include a housing that accommodates the core and the winding portion of the wire in a manner that covers at least the winding portion of the wire disposed around the winding core. Preferably, the interior of the housing is filled with a heat dissipating resin until at least a portion of the winding portion of the wire is impregnated with the heat dissipating resin.

[0025] By filling with heat-dissipating resin, the heat generated by the winding part of the core and the winding part of the wire can be efficiently transferred to the housing via the heat-dissipating resin, and the coil device can be effectively cooled. In addition, the winding part of the wire and the core can be effectively protected by the heat-dissipating resin and the housing. When the housing is made of metal, the heat dissipation is further improved, but the housing can also be made of resin (preferably a resin with excellent heat dissipation), in which case the insulation is improved.

[0026] The heat dissipating resin may be filled in the housing so as to cover the connection portion of the terminal disposed on the second surface of the base plate portion. With this configuration, the connection portion is covered with the heat dissipating resin, thereby effectively protecting the connection portion.

[0027] The terminal may also include: the wiring portion; a connecting portion having the wiring portion formed at one end; and an external connecting portion formed at the other end of the connecting portion. Preferably, the connecting portion is fixed to a fixing protrusion formed by protruding from the second surface of the base plate portion, and the top of the fixing protrusion and the external connecting portion of the terminal extend from the heat dissipating resin. By extending the external connecting portion of the terminal from the heat dissipating resin, installation of the coil device becomes easy. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1A It is a schematic perspective view of a coil device according to an embodiment of the present invention.

[0029] Figure 1B Mapping from another point of view Figure 1A A schematic perspective view of the coil device shown.

[0030] Figure 2A yes Figure 1A A schematic exploded perspective view of the coil device shown.

[0031] Figure 2B It is a schematic exploded perspective view of a coil device according to another embodiment of the present invention.

[0032] Figure 3 Yes Figure 2A A schematic exploded perspective view showing the terminal and terminal block further exploded.

[0033] Figure 4 It is along Figure 1A A cross-sectional view of the main parts of the coil device shown in III-III.

[0034] Figure 5 It means manufacturing Figure 1A A schematic perspective view of a process of the coil device shown.

[0035] Figure 6 Yes means Figure 2A A schematic perspective view showing the relationship between the lower core of the coil device shown and the terminal block.

[0036] Description of reference numerals:

[0037] 1, 1A: coil device; 2, 2A: core; 21, 21A: first core; 21a: flange; 21b: side leg; 21c: middle leg (winding core); 21c1: middle leg (winding core); 22, 22A: second core; 22a: flange; 22b, 22b1: side leg; 22c: middle leg (winding core); 24: first recess (core side passage); 24a: recessed bottom end; 24b: recessed side end; 25: second recess (core side passage); 25a: recessed bottom end; 25b: recessed side end; 3: coil body (winding portion of the conductor); 31~34: conductor; 31a~34a, 31b~3 4b: lead portion; 35: coil core assembly; 4a, 4b: terminals; 41a, 41b: wiring portion; 42: connecting portion; 43: external connection portion; 5: terminal block; 50: base plate portion; 50a: first surface; 50b: second surface; 51: first recess (base side passage); 51a: first recess bottom end; 51b: first recess side end; 52: second recess (base side passage); 52a: second recess bottom end; 52b: second recess side end; 53: frame-shaped protrusion; 54: reinforcing rib; 55: fixing protrusion; 6: housing; 60: bottom plate; 61: side plate; 62: opening end; 63: heat dissipating resin. DETAILED DESCRIPTION

[0038] The following describes the embodiments with reference to the accompanying drawings. In addition, the contents shown in the drawings are only schematic and exemplary, and the appearance, dimensional ratio, etc. may be different from the actual object. In addition, the present invention is not limited to the following embodiments.

[0039] First embodiment

[0040] Figure 1A The coil device 1 of the embodiment shown is used as a transformer, for example, for a charger, a power supply circuit of various electrical devices, etc. The coil device 1 has: a core 2, a coil body (a winding portion of a wire) 3, terminals 4a, 4b, a terminal block 5, and a housing 6. In addition, in the drawings of the specification, the X-axis, the Y-axis, and the Z-axis are perpendicular to each other, and the Z-axis is parallel to the height direction of the coil device 1 (the winding direction of the coil). In the following description, for each of the X-axis, the Y-axis, and the Z-axis, the direction toward the center of the coil device 1 is referred to as the inside, and the direction away from the center of the coil device 1 is referred to as the outside.

[0041] like Figure 2A As shown, the core 2 is composed of a first core 21 arranged on the lower side along the Z axis and a second core 22 arranged on the upper side along the Z axis of the first core 21. The first core 21 and the second core 22 are respectively composed of E-type cores, which have a substantially E-shaped cross-section parallel to the plane containing the Z axis and the X axis, but the first core 21 and the second core 22 may also be cores of different types.

[0042] For example, one core may be an E-type core and the other core may be an I-type core. In the present embodiment, the core 2 is composed of a combination of two-part cores 21 and 22, but is not limited to two-part, and may be composed of a combination of three-part, or four-part or more-part cores.

[0043] In this embodiment, if Figure 6 As shown, the first core 21 has: a flange portion 21a serving as a bottom surface parallel to a plane including an X-axis and a Y-axis; a middle leg portion (winding core portion) 21c extending from the center of the flange portion 21a toward the upper side along the Z-axis; and a pair of side leg portions 21b extending from both ends of the flange portion 21a along the X-axis toward the upper side along the Z-axis.

[0044] In addition, if Figure 2A As shown, the second core 22 has: a flange portion 22a serving as an upper surface parallel to a plane including the X-axis and the Y-axis; a middle leg portion 22c extending downward along the Z-axis from the center of the flange portion 22a; and a pair of side leg portions 22b extending downward along the Z-axis from both ends of the flange portion 22a along the X-axis. In addition, in the present embodiment, the cross-section of the middle leg portions 21c and 22c perpendicular to the Z-axis is circular, but may also be, for example, elliptical, polygonal, or other shapes.

[0045] In this embodiment, a pair of first and second recesses 24 and 25 are formed in the flange 21a of the first core 21 close to the terminal block 5. The second core 22 has the same structure as the first core 21 except that the recesses 24 and 25 are not formed.

[0046] like Figure 6 As shown in the figure, the first recess 24 and the second recess 25 are located on opposite sides of the middle leg 21c along the Y axis, and are formed to be recessed from the outer peripheral edge of the flange 21a along the Y axis toward the middle leg 21c in a cut-out shape. The flange 21a is penetrated by each recess 24 and 25 in such a way that the surface of the flange 21a along the Z axis is connected to the surface of the other side. As described later, each recess 24 and 25 constitutes a Figure 2A The core-side passages through which the lead portions 31a to 34a and 31b to 34b of the wires 31 to 34 shown in FIG.

[0047] like Figure 6 As shown, the recess 24 is formed in a manner extending in the radial direction of the middle leg 21c toward the middle leg 21c. The depth D1 of the recess 24 along the Y axis from the open end to the recessed bottom end 24a is determined in a manner that the gap D2 between the recessed bottom end 24a and the middle leg 21c is greater than 0, and the gap D2 is preferably less than 1 mm. By reducing the gap D2, for example, the lead portions 31a and 31b of the innermost circumferential side of the wire 31 arranged around the middle leg 21c can be easily passed through the recess 24, and the possibility of the lead portions 31a and 31b contacting the first core 21 is reduced.

[0048] The distance between the pair of concave side ends 24b of the concave portion 24, i.e., the width W1 of the concave portion 24 along the X-axis is smaller than, for example, the width W2 of the flange portion 21a excluding the side leg portion 21b along the X-axis, and preferably smaller than the width W3 of the middle leg portion along the X-axis. Figure 2A The wire diameters of the conductors 31 to 34 shown are large, preferably 1.5 times or more of the wire diameters of the conductors 31 to 34. The width W1 and depth D1 of the recess 24 are determined so that the conductors 31 to 34 passing through the recess 24 can easily enter the recess 24 and the magnetic properties of the first core 21 are not reduced.

[0049] In addition, the shape of the concave bottom end 24a is a flat surface in the present embodiment, but is not limited thereto and may also be a curved surface. The concave bottom end 24a and the concave side end 24b are continuous, and the corner edge where each end 24a, 24b intersects with the upper surface or the lower surface of the flange portion 21a is preferably processed into a curved surface or a conical surface. By configuring in this way, even if it is assumed that the lead portions 31a, 31b, 33a, 33b of the wires 31 and 33 passing through the concave portion 24 come into contact with the first core 21, damage to these wires 31 and 33 can be minimized.

[0050] The shapes and sizes of the concave bottom end 25a and the concave side end 25b of the concave portion 25 are determined similarly to the concave bottom end 24a and the concave side end 24b of the concave portion 24, and are preferably the same shape and the same size, but the shapes do not necessarily have to be the same and the sizes may be different.

[0051] The cores 21 and 22 are not particularly limited as long as they are cores having magnetic bodies, and are made of, for example, ferrite, metal magnetic bodies, or resin containing magnetic powder. Figure 6 The front end of the middle leg portion 21c is shown Figure 2A The front ends of the middle leg portion 22c shown in the figure are butted together to form the winding core, and the front ends of the side leg portions 21b are butted together and in contact with the front ends of the side leg portions 22b. However, in another embodiment, the front ends of the middle leg portions 21c and 22c may not be in direct contact, but a gap may be formed between them. Figure 1B The heat dissipating resin 63 shown may enter the gap, or other components may be interposed in the gap.

[0052] like Figure 2A As shown, the two cores 21 and 22 can be integrated by using an adhesive, or can be integrated by using a fixing tape, etc., after the coil body 3 is assembled therebetween, or can be integrated by combining them. As the adhesive, a resin material with excellent thermal conductivity such as heat dissipation grease can be used.

[0053] In the present embodiment, the coil body 3 is a winding portion of a conductor wound with a plurality of conductors 31 to 34. For example, in the present embodiment, a winding portion of a conductor 32 is arranged around the winding portion of the conductor 31, a winding portion of a conductor 33 is arranged around the winding portion of the conductor 32, and a winding portion of a conductor 34 is arranged around the winding portion of the conductor 33. For example, the conductor 31 has a pair of lead portions 31a and 31b drawn out from the winding portion of the conductor 31, the conductor 32 has a pair of lead portions 32a and 32b drawn out from the winding portion of the conductor 32, the conductor 33 has a pair of lead portions 33a and 33b drawn out from the winding portion of the conductor 33, and the conductor 34 has a pair of lead portions 34a and 34b drawn out from the winding portion of the conductor 34.

[0054] In the present embodiment, each of the conductors 31 to 34 is composed of, for example, a self-fusing conductive wire having an insulating layer and a welding layer. The type of the conductive wire is not particularly limited, and examples thereof include conductive core wires such as round wires, flat wires, stranded wires, Litz wires, and braided wires. The material of the welding layer or the insulating layer covering the core wire is not particularly limited, and examples thereof include polyurethane, polyamide-imide, polyimide, polyester, and the like.

[0055] Furthermore, in the present embodiment, the wires 31 to 34 are all composed of self-fusing wires, but at least one of them may be a self-fusing wire, or all of them may be composed of other wires.

[0056] The wire diameters of the conductors 31 to 34 may be the same or different, and are not particularly limited, but may be, for example, in the range of 1.0 to 3.0 mm. The conductors 31 to 34 may be directly wound helically around the middle leg portions 21 c and / or 22 c of at least one of the cores 21 or 22, but are preferably formed into air-core coils in advance and then arranged around the middle leg portions 21 c and 22 c of the cores 21 and 22.

[0057] like Figure 2A As shown, a plurality of terminals 4a, 4b are mounted on the terminal block 5. In the present embodiment, the terminal block 5 has two types of terminals 4a, 4b, but may also have one type of terminal, or may have more than three types of terminals. In the present embodiment, two pairs of the two types of terminals 4a, 4b are mounted at both ends of the terminal block 5 along the Y axis.

[0058] like Figure 3 As shown, the terminal 4a has: a connection portion 41a, an external connection portion 43 and a connection portion 42 connecting them. The terminal 4b has: a connection portion 41b, an external connection portion 43 and a connection portion 42 connecting them. The difference between the terminal 4a and the terminal 4b is that the length of the connection portion 41a is longer than the length of the connection portion 41b, and the terminal 4a and the terminal 4b have the same structure. These terminals 4a and 4b can be formed by, for example, stamping a metal plate.

[0059] In the present embodiment, the plurality of terminals 4 a and 4 b are mounted on the terminal block 5 by insert molding as described later, but may be mounted by inserting into the terminal block 5 or by bonding.

[0060] like Figure 6 As shown, in this embodiment, the terminal block 5 has a base plate portion 50, and the base plate portion 50 has a plane parallel to the X axis and the Y axis. The shape of the outer periphery of the base plate portion 50 matches the shape of the outer periphery of the first core 21 (and the second core 22) and is rectangular, but it can also be other shapes, such as polygonal, circular, elliptical or other shapes.

[0061] The base plate portion 50 has a first surface 50a and a second surface 50b, wherein the lower surface of the flange portion 21a of the first core 21 along the Z axis is mounted on the first surface 50a, and the second surface 50b is located on the side opposite to the first surface 50a. The lower surface of the flange portion 21a of the first core 21 along the Z axis can be fixed to the upper surface of the base plate portion 50 by an adhesive or the like, or can be fixed by other means. In addition, the fixation between the first core 21 and the second core 22 can be based on an adhesive, or can also be fixed by other methods.

[0062] The base plate portion 50 is provided with a first recess 51 and a second recess 52 so as to match the positions of the recesses 24 and 25 of the first core 21. The first recess 51 and the second recess 52 are located on opposite sides of each other along the Y axis with the middle leg portion 21c of the first core 21 interposed therebetween, and are formed so as to be recessed from the outer peripheral edge of the base plate portion 50 toward the center along the Y axis in a cut-out shape.

[0063] The base plate 50 is penetrated by each of the recesses 51 and 52 so that the first surface 50a on one side and the second surface 50b on the other side along the Z axis of the base plate 50 are connected. Each of the recesses 51 and 52 is aligned with and connected to each of the recesses 24 and 25, respectively, to form a structure for providing Figure 2A The lead portions 31a to 34a and 31b to 34b of the wires 31 to 34 shown in FIG. 3 are substrate-side vias through which the lead portions 31a to 34a and 31b to 34b of the wires 31 to 34 are passed.

[0064] like Figure 6 As shown, the depth D2 of the recess 51 from the opening end to the recess bottom end 51a along the Y axis is preferably equal to the depth D1 of the first recess 24 of the first core 21, and may be greater than it, but it is preferred that the recesses 51 and 52 are not connected. The distance between the pair of recess side ends 51b of the recess 51, that is, the width W2 of the recess 51 along the X axis is preferably equal to the width W1 of the recess 24 of the first core 21, for example, but may be wider than it. The width W2 and depth D2 of the recess 51 are determined in such a way that the conductive wires 31 to 34 passing through the recess 51 can easily enter the recess 51.

[0065] In addition, the shape of the concave bottom end 51a is a flat surface in the present embodiment, but is not limited thereto and may also be a curved surface. The concave bottom end 51a and the concave side end 51b are continuous, and the corners where the ends 51a, 51b intersect with the first surface 50a or the second surface 50b of the base plate portion 50 are preferably processed into a curved surface or a tapered surface. By configuring in this way, even if the lead portions 31a, 31b, 33a, 33b of the wires 31 and 33 passing through the concave portion 51 come into contact with the concave bottom end 51a or the concave side end 51b, damage to the wires 31 and 33 can be minimized.

[0066] The shapes and sizes of the concave bottom end 52a and the concave side end 52b of the concave portion 52 are determined similarly to the concave bottom end 51a and the concave side end 51b of the concave portion 51, and are preferably the same shape and the same size, but the shapes do not necessarily have to be the same and the sizes may be different.

[0067] A frame-shaped protrusion 53 is provided on the outer periphery of the base plate portion, and the frame-shaped protrusion 53 surrounds at least a portion of the first core 21 including the flange portion 21a in a manner of protruding upward along the Z axis from the first surface 50a of the base plate portion 50. In the present embodiment, the frame-shaped protrusion 53 is integrally formed on the base plate portion 50 in a manner of surrounding the outer periphery other than the recesses 24 and 25 of the first core 21. The protruding height of the frame-shaped protrusion along the Z axis is not particularly limited, and for example, it can be greater than 1 / 5 of the thickness of the flange portion 21a along the Z axis and less than the same thickness. The size of the inner periphery of the frame-shaped protrusion 53 is determined in a manner that the flange portion 21a of the first core 21 is accommodated in the frame-shaped protrusion 53, and the positions of the recesses 24 and 25 of the flange portion 21a and the positions of the recesses 51 and 52 of the base plate portion 50 can be aligned.

[0068] like Figure 3 As shown, a reinforcing rib 54 extending along the X-axis is formed integrally with the base plate portion 50 at the center portion along the Y-axis of the second surface 50b of the base plate portion 50. The portion where the reinforcing rib 54 is located protrudes from the second surface 50b of the base plate portion 50 compared to other portions, and the thickness of the plate becomes larger, so that the strength of the base plate portion 50 formed with the recessed portions 51 and 53 is enhanced, and deformation such as warping of the base plate portion 50 is effectively prevented.

[0069] In addition, at both ends of the base plate portion 50 along the Y axis, in the portion other than the recessed portions 51 and 52, a fixing convex portion 55 is integrally formed so as to protrude downward along the Z axis from the second surface 50b. The protruding height of the fixing convex portion 55 from the second surface 50b is preferably greater than the protruding height of the reinforcing rib 54. The fixing convex portion 55 is divided into four in total along the X axis by each recessed portion 51 or 52, and a pair of terminals 4a, 4b are fixed to each convex portion 55.

[0070] In fact, the connection parts 42 of the terminals 4a and 4b are integrated in a manner of being embedded in the fixing part 55. Figure 1B As shown, each of the wiring portions 41a, 41b is located on the second surface 50b side of the base plate portion 50 from the inner side (the center side along the Y axis) of the fixing portion 55. In addition, the external connection portion 43 of each of the terminals 4a, 4b extends from the protruding top of the fixing portion 55 and extends to the outside of the housing 6. The external connection portion 43 is connected to an external connection terminal not shown or a terminal connection portion of a circuit substrate.

[0071] In addition, in the present embodiment, each of the connecting portions 41a, 41b extends linearly from the fixing portion 55, but the present invention is not limited thereto and may extend in a curved shape. In addition, the protruding front ends of each of the connecting portions 41a, 41b of the lead portions 31a, 31b (or 32a, 32b) and the lead portions 33a, 33b (or 34a, 34b) to which the wires are respectively connected through the same recess 51 (or 52) and taken out to the second surface 50b side face the same side along the Y axis, but the present invention is not limited to such an arrangement.

[0072] In this embodiment, the terminal block 5 has at least a base plate portion 50, but preferably has at least one of a frame-shaped protrusion 53, a reinforcing rib 54, or a fixing protrusion 55, which are integrally formed with the terminals 4a, 4b by insert molding of an insulating resin, etc. In addition, including the base plate portion 50, the terminal block 5 may also be composed of insulating components other than resin.

[0073] In addition, in this embodiment, Figure 2A The lead portions 31a, 31b, 33a, 33b of the wires 31 and 33 shown in FIG. 1 are passed through the first recess 24 of the first core 21 and the first recess 51 of the base plate portion 50. Figure 1B As shown, the terminals 41a and 41b are connected to the front ends of the respective wiring portions 41a and 41b arranged on the second surface 50b in a contact or non-contact state.

[0074] and, Figure 2A The lead portions 32a, 32b, 34a, 34b of the wires 32 and 34 shown in FIG. 1 pass through the second recess 25 of the first core 21 and the second recess 52 of the base plate portion 50, as shown in FIG. Figure 1B As shown, the terminals 41a and 41b are connected to the front ends of the respective wiring portions 41a and 41b arranged on the second surface 50b in a contact or non-contact state.

[0075] There is no particular limitation on the method of connecting them, but laser welding is preferably performed in addition to riveting, but other methods may be used for connection. Other methods include riveting, thermocompression, resistance connection, and soldering.

[0076] like Figure 5 As shown, in this embodiment, the coil core assembly 35 is received in the housing 6 from the open end of the housing 6 filled with the heat dissipating resin 63. In the coil core assembly 35, the core 2 is fixed to the terminal block 5 having the terminals 4a and 4b. The core 2 is equipped with the coil body 3. The terminals 4a and 4b are connected to the lead parts of the coil body 3. In addition, the heat dissipating resin 63 can also be filled after the coil core assembly 35 is received in the housing 6 from the open end 62. Figure 5 In the vertical direction (the direction of the arrow on the Z axis) Figure 1A to Figure 4 and Figure 6 is opposite to the coil device 1 shown in the figure. Figure 6

[0077] In the present embodiment, the housing 6 has a substantially rectangular bottom plate 60 and side plates 61. The side plates 61 stand upward along the Z-axis from the four-side positions of the bottom plate 60, and a bottomed accommodation space is formed inside. An open end 62 is formed at the upper part along the Z-axis. Figure 5 Figure 5 The housing 6 is preferably made of a metal such as aluminum with excellent thermal conductivity, but may also be made of resin. Figure 5

[0078] Preferably, more than half of the coil core assembly 35 is accommodated inside the housing 6, and the liquid level of the heat-dissipating resin 63 filled inside the housing 6 (the interface between the cured resin and air) is at a position where at least half of the coil body 3 is filled with the heat-dissipating resin 63. Further preferably, the liquid level of the heat-dissipating resin 63 filled inside the housing 6 is at a position above where at least the entire coil body 3 is filled with the heat-dissipating resin 63. Particularly preferably, the wiring portions 41a and 41b of the terminals 4a and 4b are covered with the heat-dissipating resin 63, and the protruding top surface of the fixing convex portion 55 is exposed from the liquid level of the heat-dissipating resin 63.

[0079] The heat-dissipating resin 63 is also called potting resin and is composed of silicone resin (Japanese: シリコーン樹脂), urethane resin (Japanese: ウレタン樹脂), epoxy resin, etc. that are still soft after injection. The longitudinal elastic modulus of the potting resin is preferably 0.1 to 100 MPa. In the present embodiment, for example, through the heat-dissipating resin 63 and the housing 6, the heat generated in the winding portion of the first wire 31, the winding portion of the second wire 32, and the core 2 can be efficiently dissipated to the outside of the housing 6, improving the cooling efficiency of the coil device 1.

[0078]

[0080] In addition, in Figure 2A the coil body 3 shown in the figure, when there is a gap between the winding portion of the first wire 31 located on the innermost peripheral side and the outer peripheral surface of the middle leg portion 21c or 22c of the core 2, through this gap,

[0080] Figure 5 the heat-dissipating resin 63 shown in the figure is interposed therebetween, so that Figure 2A Figure 2A the heat dissipation of the outer peripheral surfaces of the middle leg portions 21c and 22c and the inner peripheral surface of the winding portion of the coil body 3 is improved. Figure 5

[0081] In the coil device 1 of the present embodiment, as shown in Figure 2AAs shown, a recess 51 or 52 is formed in the base plate portion 50 as a base side passage, and the recess 51 or 52 allows at least a portion of the lead portions 31a to 34a and 31b to 34b of the conductors 31 to 34 from the coil body 3 to pass through and guide to the connection portions 41a and 41b. Therefore, the lead portions 31a to 34a and 31b to 34b of the conductors 31 to 34 become less likely to abut against the outer peripheral edge of the base plate portion 50. As a result, the insulating coating of the lead portions 31a to 34a or 31b to 34b of the conductors 31 to 34 is less likely to be damaged, and poor insulation and disconnection of the lead portions 31a to 34a or 31b to 34b of the conductors 31 to 34 can be effectively prevented, thereby improving the reliability of the coil device 1.

[0082] In addition, in the present embodiment, the recessed portion 51 or 52 as the base side passage formed in the base plate portion 50 is a notch-shaped recessed portion penetrating the first surface 50a and the second surface 50b. With such a configuration, when the lead portions 31a to 34a or 31b to 34b of the wires 31 to 34 are guided through the base plate portion 50 by the notch-shaped recessed portion 51 or 52, the lead portions 31a to 34a or 31b to 34b of the wires 31 to 34 are less likely to come into contact with the outer peripheral edge of the base plate portion 50.

[0083] Furthermore, since the lead wires 31a to 34a or 31b to 34b of the plurality of conductors 31 to 34 can be guided through the recesses 51 and 52 of the base plate portion 50, the lead wires 31a to 34a or 31b to 34b do not hinder the winding of the conductors, and the conductors can be wound tightly, thereby increasing the conductor occupancy rate. In addition, since it is easy to overlap and wind the plurality of conductors 31 to 34 in the radial direction, this also contributes to the thinning of the coil device.

[0084] like Figure 6 As shown in the present embodiment, the concave edge ends (inner peripheral edge ends) 51a, 52a of the concave portions 51, 52 as the base side passages extend to the vicinity of the middle leg portion 21c as the winding core portion. With this configuration, when the lead portions 31a to 34a, 31b to 34b of the conductor wire are arranged around the middle leg portion 21c, Figure 2A When the coil body 3 shown is guided to the connection portions 41 a and 41 b located on the second surface 50 b of the base plate portion 50 , the lead portions 31 a to 34 a and 31 b to 34 b of the conductive wires are less likely to come into contact with the outer peripheral edge of the base plate portion 50 .

[0085] like Figure 6As shown, in this embodiment, the core 2 has a flange portion 21a magnetically connected to the middle leg portion 21c. The flange portion 21a is arranged on the base plate portion 50, and has each recess 24, 25 connected to each recess 51, 52. With such a configuration, the lead portions 31a~34a, 31b~34b of the conductor can be guided from the coil body 3 arranged around the middle leg portion 21c to the connection portions 41a, 41b located on the second surface 50b of the base plate portion 50 through each recess 24, 25 connected to each recess 51, 52.

[0086] Therefore, the lead wire portions 31a to 34a, 31b to 34b of the conductive wire are less likely to abut against the outer peripheral edge of the base plate portion 50, and are also less likely to abut against the outer peripheral edge of the flange portion 21a of the core. As a result, the insulating coating of the lead wire portions 31a to 34a, 31b to 34b of the conductive wire is less likely to be damaged, and poor insulation and disconnection of the lead wire portions 31a to 34a, 31b to 34b of the conductive wire can be further effectively prevented, and the reliability of the coil device 1 is further improved.

[0087] In addition, the base plate portion 50 has a frame-shaped protrusion 53 that surrounds at least a portion of the core 2 including the flange portion 21a in a manner protruding from the first surface 50a of the base plate portion 50. The protrusion 53 can position the core 2 relative to the base plate portion 50 and can improve the insulation between the core 2 arranged on the first surface 50a and the connection portions 41a, 41b of the terminals 4a, 4b arranged on the second surface 50b.

[0088] Furthermore, as the core side passage, one of at least a pair of recesses 24 and 25 and the other are located on opposite sides of each other around the middle leg portion 21c along the Y axis. With such a configuration, a method of use such as passing the lead wire portion of the wire constituting the primary side coil through one of the pair of recesses 24 and 25 and passing the lead wire portion of the wire constituting the secondary side coil through the other can be realized, and it is easy to make the terminals to which the lead wire portions of the wires requiring high insulation are respectively connected be located on opposite sides of each other around the core portion.

[0089] like Figure 5 As shown, the coil device 1 further includes a housing 6, which accommodates a coil core assembly 35 having a core 2 and a coil body 3 in a manner that covers at least the coil body 3. The interior of the housing 6 is filled with a heat dissipating resin 63, and the heat dissipating resin 63 is filled to a position where at least a portion of the coil body 3 is impregnated.

[0090] By filling the heat dissipating resin 63, the heat generated by the middle leg portions 21c, 22c of the core 2 and the coil body 3 can be efficiently transferred to the housing 6 via the heat dissipating resin 63, and the coil device 1 can be effectively cooled. In addition, the coil body 3 and the core 2 can be effectively protected by the heat dissipating resin 63 and the housing 6. When the housing 6 is made of metal, the heat dissipation is further improved, but the housing 6 can also be made of resin (preferably a resin with excellent heat dissipation), in which case, the insulation is improved.

[0091] like Figure 4 As shown, the housing 6 is preferably filled with heat-dissipating resin 63 so as to cover the connection portions 41a and 41b of the terminals disposed on the second surface 50b of the base plate portion 50. With this configuration, the connection portions 41a and 41b are covered with the heat-dissipating resin 63, thereby effectively protecting the connection portions 41a and 41b.

[0092] The terminals 4a and 4b include: connecting portions 41a and 41b; a connecting portion 42 having a connecting portion formed at one end; and an external connecting portion 43 formed at the other end of the connecting portion 42. The connecting portion 42 is fixed to a fixing protrusion 55 formed to protrude from the second surface 50b of the base plate portion 50, and the top of the fixing protrusion 55 and the external connecting portion 43 of the terminals 4a and 4b extend from the heat dissipation resin 63. By extending the external connecting portion 43 of the terminals 4a and 4b from the heat dissipation resin 63, the coil device 1 can be easily mounted.

[0093] Second embodiment

[0094] exist Figure 2B The coil device 1A of the present embodiment shown has the same structure and the same operational effects as the core 2 of the coil device 1 of the above-described embodiment except that the structure of the core 2A is different.

[0095] exist Figure 2B In the illustrated embodiment, the core 2A is composed of a first core 21A, a second core 22A, and a pair of side legs 22 b 1 , and the structure of the final core after the combination is the same as that of the core 2 .

[0096] In this embodiment, the two middle legs 21c and 22c in the core 2 of the above-mentioned embodiment are integrated into a middle leg 22c1 and integrated with the flange 22a. In addition, the pair of side legs 21b and the pair of side legs 22b in the core 2 of the above-mentioned embodiment are respectively integrated into a side leg 22b1, which is formed separately from the flange 21a and the flange 22a, and is respectively joined to the two ends of these flanges 21a and the flange 22a along the X-axis.

[0097] In addition, the present invention is not limited to the above-mentioned embodiment, and various changes can be made within the scope of the present invention.

[0098] For example, in the above-mentioned embodiment, if Figure 6 As shown in the figure, the base plate portion 50 has recesses 51 and 52 formed on both sides along the Y axis, which are roughly rectangular when viewed from the Z axis direction, but may also be in shapes other than roughly rectangular, such as triangle, polygon, part circle, part ellipse or other shapes. In addition, only one of the recesses 51 or 52 may be formed on the base plate portion 50, or three or more recesses may be formed. In addition, instead of the cutout-shaped recesses 51 or 52, a hole penetrating the first surface 50a and the second surface 50b of the base plate portion 50 may be set as a base side passage.

[0099] In addition, the recessed portion 24 or 25 formed in the flange portion 21a matches the shape of the recessed portions 51 and 52, and is roughly rectangular when viewed from the Z-axis direction, but may also be a shape other than a roughly rectangular shape, such as a triangle, a polygon, a partial circle, a partial ellipse, or other shapes. In addition, only one of the recessed portions 24 or 25 may be formed in the flange portion 21a, or more than three recessed portions may be formed. In addition, a through hole may be provided as a core-side passage instead of the cut-out recessed portion 24 or 25.

[0100] In addition, the size of the recesses 24 and 25 is preferably substantially equal to the size of the recesses 51 and 52, but they do not necessarily have to be equal, and the width W1 of the recesses 24 and 25 may be different from the width W2 of the recesses 51 and 52. For example, the width W1 of the recesses 24 and 25 may be larger than the width W2 of the recesses 51 and 52, or vice versa. For example, when the width W1 of the recesses 24 and 25 is larger than the width W2 of the recesses 51 and 52, it is possible to effectively prevent the lead portion of the wire from strongly contacting the edge portion of the recessed side end 24b and 25b of the recesses 24 and 25.

[0101] In addition, the depth D1 of the recesses 24 and 25 is preferably substantially equal to the depth D2 of the recesses 51 and 52, but may be different. For example, the depth D1 of the recesses 24 and 25 may be greater than the depth D2 of the recesses 51 and 52, or vice versa. For example, when the depth D1 of the recesses 24 and 25 is greater than the depth D2 of the recesses 51 and 52, it is possible to effectively prevent the lead portion of the wire from strongly contacting the edge portion of the recessed bottom end 24a, 25a of the recesses 24 and 25.

Claims

1. A coil device, comprising: a core having a winding core portion; a winding portion of the conductive wire, which is spirally arranged around the winding core portion; and a base plate portion on which a terminal is mounted, the terminal being connected to a lead portion of the wire led out from the winding portion, The core having the winding core portion is provided on one first surface of the base plate portion. A connection portion of the terminal is arranged on the other second surface of the base plate portion located on the side opposite to the first surface. The base plate portion has a base-side passage formed therein, the base-side passage allowing the lead portion of the conductive wire from the winding portion to pass therethrough and guide the lead portion toward the connecting portion.

2. The coil device according to claim 1, characterized in that The base-side passage formed in the base plate portion is a notch-shaped recess or a through hole penetrating the first surface and the second surface.

3. The coil device according to claim 1, characterized in that An inner peripheral edge end of the base-side passage extends to the vicinity of the winding core.

4. The coil device according to claim 1, characterized in that The core has a flange portion magnetically connected to the winding core portion, The flange portion is disposed on the base plate portion and has a core-side passage communicating with the base-side passage.

5. The coil device according to claim 4, characterized in that The base plate portion has a convex portion that surrounds at least a portion of a core including the flange portion so as to protrude from the first surface of the base plate portion.

6. The coil device according to claim 1, characterized in that The core side passage has at least one pair of core side passages, One and the other of the pair of core-side passages are located on opposite sides to each other around the winding core.

7. The coil device according to claim 1, characterized in that A housing is further provided, which accommodates the core and the winding portion of the wire so as to cover at least the winding portion of the wire arranged around the winding core portion. The housing is filled with a heat-dissipating resin to a position where at least a portion of the winding portion of the lead wire is immersed.

8. The coil device according to claim 7, characterized in that The heat-dissipating resin is filled in the case so as to cover the connection portion of the terminal disposed on the second surface of the base plate portion.

9. The coil device according to claim 8, characterized in that The terminal comprises: the wiring portion; a connecting portion having the wiring portion formed at one end; and an external connecting portion formed at the other end of the connecting portion. The connecting portion is fixed to a fixing protrusion formed to protrude from the second surface of the base plate portion. The top of the fixing protrusion and the external connection portion of the terminal protrude from the heat-dissipating resin.

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