JP7200815B2 - Coil device - Google Patents

Description

The present invention relates to a coil device that can be suitably used as, for example, a transformer.

For example, as a coil device used in transformers, etc., the coil device shown in Patent Document 1 is known. In this type of conventional coil device, an inner coil is wound around the outer peripheral surface of an inner bobbin, a bobbin cover surrounds it, and an outer coil is wound around the outer periphery of the bobbin cover.

In such a coil device, the coupling between the outer coil and the inner coil can be adjusted (for example, the leakage characteristics can be adjusted) by shifting the axial positions of the inner coil and the outer coil. Common.

However, it has become difficult to reduce the height of the coil device by adjusting the coupling between the coils only by shifting the axial positions of the inner coil and the outer coil, as in the conventional art.

Japanese Patent No. 6268509

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and an object of the present invention is to provide a coil device that facilitates adjustment of coupling between coils and can be made thinner.

In order to achieve the above object, the coil device according to the present invention includes:
a bobbin having a first winding portion around which a first wire is wound;
A coil device comprising a bobbin cover that covers the bobbin around which the first wire is wound,
The bobbin cover includes a second winding portion around which a second wire different from the first wire is wound, and a position below or above the second winding portion along the axial direction. and a non-wound portion;
Compared to the number of main winding layers of the first wire wound around the first main winding portion of the first winding portion located inside the second winding portion, the number of the non-winding portions is The number of sub-winding layers of the first wire wound around the first sub-winding portion of the first winding portion located inside is large.

In the coil device of the present invention, the coupling between the coils is achieved in the radial gap between the first wire wound around the first main winding portion and the second wire wound around the second winding portion. can be adjusted (for example, the leakage characteristic can be adjusted). Furthermore, in the coil device of the present invention, even in the axial gap between the first wire wound around the first sub-winding portion and the second wire wound around the second winding portion, Coupling can be adjusted. In addition, if the number of winding layers of the first wire wound around the first sub-winding portion is increased, the overlapping area between the first wire and the second wire when viewed in the axial direction also increases, and the coupling between the coils increases. Adjustment is possible. Thus, in the coil device of the present invention, it is easy to adjust the coupling between the coils in both the radial clearance and the axial clearance.

Further, in the coil device of the present invention, the total number of turns of the first wire is increased by increasing the number of winding layers of the first wire wound on the first sub-winding portion of the first winding portion. Therefore, the axial dimension of the bobbin can be shortened. Therefore, it is possible to reduce the height of the coil device.

Preferably, the position of the outermost layer of the first wire wound around the first sub-winding portion is located outside the tubular wall of the second winding portion. With this configuration, the wound first wire and the wound second wire overlap when viewed in the axial direction. Therefore, the coupling between the coils can be adjusted by the axial gap between the first wire wound around the first sub-winding portion and the second wire wound around the second winding portion. become easier.

Preferably, the first wire wound around the first sub-winding portion and the second wire wound around the second winding portion overlap each other when viewed in the axial direction. With this configuration, the inter-coil coupling is achieved in the axial gap between the first wire wound around the first sub-winding portion and the second wire wound around the second winding portion. It is easy to adjust the

Preferably, the first winding portion has winding partition ribs formed at predetermined intervals along the axial direction. By configuring in this way, α-winding of the first wire is facilitated. Further, preferably, the winding partition brim that separates the first main winding portion and the first sub-winding portion has the winding partition brim formed within the range of the first main winding portion. A protrusion projecting outward from the outer edge is formed. This convex portion can also function as positioning with the bobbin cover.

Preferably, the projection has a notch forming a flow gap penetrating in the axial direction. Through this notch, a high thermal conductive resin such as potting resin can flow in the axial direction. As a result, the highly thermally conductive resin spreads over the inner coil portion composed of the first wire positioned inside, thereby improving heat dissipation.

Preferably, the bobbin cover includes
a second hollow cylindrical portion constituting the second winding portion;
a pair of cover brim portions formed at both ends of the second hollow cylindrical portion in the axial direction;
A plurality of gap holding pieces constituting the non-wound portion are intermittently formed along the circumferential direction on the outer periphery of at least one of the cover flange portions,
The first sub winding portion is positioned inside the gap holding piece.

By configuring in this way, it becomes easy to wind the first wire around the outer circumference of the first sub-winding portion with a large number of turns.

Preferably, the gap holding piece is formed with an opening connecting the outside and the inside of the gap holding piece. By configuring in this way, a highly thermally conductive resin such as a potting resin can flow radially inward through the opening. As a result, the highly thermally conductive resin spreads over the inner coil portion composed of the first wire positioned inside, thereby improving heat dissipation. It is preferable that the position where the opening is formed correspond to the position where the notch of the convex portion is formed. This is because the high thermal conductive resin can easily flow inside the bobbin cover.

Preferably, the first wire is α-wound around the first main winding portion and the first sub-winding portion. The α-winding facilitates the winding of the first wire and reduces the axial length of the coil portion formed by the first wire. Also, the first wire can be easily wound in many turns around the outer periphery of the first sub-winding portion.

Preferably, the coil device further includes a case containing the high thermal conductivity resin such that the first winding portion of the bobbin and the second winding portion of the bobbin cover are filled with the high thermal conductivity resin. have. This easy configuration makes it possible to reduce the height of the coil device and further improve heat dissipation.

1A is a perspective view of a coil device according to a first embodiment of the present invention; FIG. FIG. 1B is a perspective view of a coil device according to a second embodiment of the invention. 2A is an exploded perspective view of the coil device shown in FIG. 1. FIG. FIG. 2B is an exploded perspective view when each member attached to the bobbin is removed from the coil device shown in FIG. 2A. FIG. 2C is an exploded perspective view when each member attached to the bobbin is removed from the coil device shown in FIG. 2B. 2D is a perspective view showing the lead portion of the outer coil shown in FIG. 2B and its peripheral structure. FIG. FIG. 2E is an exploded perspective view when the lead drawing block attached to the bobbin is removed from the coil device shown in FIG. 2B. FIG. 3 is a cross-sectional view of the coil device taken along line III--III shown in FIG. 1A. 4A is a perspective view showing a lead portion of an outer coil and its peripheral structure in the coil device shown in FIG. 1A. FIG. 4B is a perspective view showing a lead portion of an outer coil and its peripheral structure in the coil device shown in FIG. 1B. FIG. 5A is an exploded perspective view of the insulation protector shown in FIG. 4A. FIG. FIG. 5B is an exploded perspective view of the insulation protector shown in FIG. 4B. FIG. 6 is a schematic perspective view explaining α-winding of the first wire around the bobbin.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described based on embodiments shown in the drawings.

First Embodiment As shown in FIG. 1A, a coil device 10 according to one embodiment of the present invention has a case 300 , and the main parts of the coil device 10 are housed inside the case 300 . In this embodiment, in the drawing, the X-axis, the Y-axis, and the Z-axis are perpendicular to each other, the Z-axis is perpendicular to the mounting surface of the coil device 10, and the pair of terminals 91 and 92 and the pair of The X-axis is the direction in which the terminals 91 and 92 of are positioned opposite to each other.

As shown in FIG. 2A, the case 300 includes a frame 305 having an outer side surface 310 and an inner side surface 320, and a bottom plate 340 joined to an opening edge 315 of the frame 305 on the Z-axis lower side. An upper plate or the like is not joined to an opening edge 330 on the Z-axis upper side of the frame 305 and is open upward, so that the main part of the coil device 10 can be inserted from above. Four corners of the frame 305 may be formed with concave corners 350 recessed inside the frame 305 so as to match the overall shape of the coil device 10 .

The frame 305 of the case 300 is preferably made of metal or the like with good thermal conductivity. The metal forming the frame 305 is not particularly limited, but examples thereof include aluminum, aluminum alloys, copper, copper alloys, and stainless steel. Frame 305 of case 300 can be manufactured by, for example, extrusion molding, press working, or die casting.

Similarly, the bottom plate 340 is preferably made of the same metal as that of the frame 305 , but does not have to be made of exactly the same metal as that of the frame 305 . The bottom plate 340 is joined to the frame 305 with an adhesive or the like, but may be joined with bolts and nuts. Alternatively, the bottom plate 340 and the frame 305 may be integrally formed. A cooling device such as a cooling pipe, cooling fins, or the like may be mounted directly below the case 300 via a metal plate or the like.

A highly thermally conductive resin is previously accommodated inside the case 300 , and the main portion of the coil device 10 is immersed in the highly thermally conductive resin inside the case 300 . Although the high thermal conductivity resin is not particularly limited, for example, a resin having a thermal conductivity of 0.5 to 5 W/m·K, preferably 1 to 3 W/m·K and having excellent heat dissipation properties is preferable.

Examples of resins having excellent high thermal conductivity include silicone resins, urethane resins, and epoxy resins, among which silicone resins and urethane resins are preferred. Moreover, in order to improve heat dissipation, the resin may be filled with a filler having high thermal conductivity. The high thermal conductivity resin of the present embodiment preferably has a Shore A hardness of 100 or less, preferably 60 or less. A potting resin is exemplified as such a resin.

As shown in FIG. 2A, the coil device 10 has four cores 12, bobbins 40, bobbin covers 50, and two core covers 60. As shown in FIG. The four cores 12 are assembled to form a magnetic path through which the magnetic flux generated by the coils described below passes. These cores 12 have symmetrical shapes and are connected to each other so as to sandwich the bobbin cover 50 and the bobbin 40 from above and below (the Z-axis direction in the figure).

Each core 12 has a substantially E-shaped vertical cross section (a cross section including the Y axis and the Z axis). Each core 12 is made of a soft magnetic material such as ferrite or a metal magnetic material. It has side legs 16 , 16 and a middle leg 14 projecting in the Z-axis direction from an intermediate position in the Y-axis direction of each base 13 .

In this embodiment, the middle leg 14 of each core 12 is inserted into the first through hole 44 a formed in the first hollow cylinder portion 44 of the bobbin 40 . A gap is formed between the cores 12 , 12 adjacent to each other in the X-axis direction by the separation projection 44 b formed on the inner peripheral wall of the first hollow cylindrical portion 44 . High thermal conductivity resin such as potting resin enters this gap, thereby improving the heat radiation property of the heat generated inside the coil device 10 .

The gap formed by the separation protrusion 44b corresponds to the thickness of the separation protrusion 44b in the X-axis direction. The separating protrusions 44b are formed along the Z-axis on both sides in the Y-axis direction at the central portion in the X-axis direction inside the through-hole 44a. Although the thickness of the separating projection 44b in the X-axis direction is not particularly limited, it is preferably 0.05 to 5 mm, more preferably 0.1 to 3 mm.

As shown in FIG. 2B, the bobbin 40 has a substantially elliptical flat bobbin substrate 42 at its lower end in the Z-axis direction. As shown in FIG. 3, a first hollow cylindrical portion 44 is integrally formed on the substantially central portion of the bobbin substrate 42 so as to extend upward in the Z-axis direction.

As shown in FIG. 3, a bobbin upper collar portion 48 is integrally formed on the upper portion of the first hollow cylindrical portion 44 in the Z-axis direction so as to protrude radially from the first hollow cylindrical portion 44 on the Y-axis-X-axis plane. There is. As shown in FIG. 2C, lead drawer bases 491 are integrally formed at both ends of the bobbin upper collar portion 48 in the X-axis direction. A lead drawing portion 49 formed separately from the bobbin 40 can be joined to each lead drawing base 491 by fitting or adhesion. Note that the lead drawing portion 49 may be formed integrally with the bobbin 40 .

In this embodiment, each lead drawing part 49 is configured by a lead drawing block 490 as a terminal block, and as shown in FIG. A pair of lead portions 22a, 22a, which are both ends of 22, has a pedestal 49c formed with a pair of vertical lead-out grooves 490e that are led out upward in the Z-axis direction. The pedestal 490a is formed with horizontal lead-out grooves 490f leading to the opposite side in the Y-axis direction above the vertical lead-out grooves 490e in the Z-axis direction. Each lead portion 22a, 22a is guided in each horizontal extraction groove 490f. Lead connection pieces 91a, 92a of the terminals 91, 92 are connected to the ends of the respective lead portions 22a, 22a. The terminals 91 and 92 are embedded and integrated in the pedestal 490a, but they do not have to be embedded.

The other lead drawing block 490 shown in FIG. 2C has the same structure except that the lead portion 22a of the lead block 490 is replaced with the lead portion 32a. That is, the other lead drawer block 490 shown in FIG. 2C is a pair of vertical drawers from which a pair of lead portions 32a, 32a, which are both end portions of the second wire 32 constituting the outer coil 30, are drawn out in the upward direction of the Z axis. It has a pedestal 490a with a groove 490e formed therein. The pedestal 490a is formed with horizontal lead-out grooves 490f leading to the opposite side in the Y-axis direction above the vertical lead-out grooves 490e in the Z-axis direction. Each lead portion 32a, 32a is guided in each horizontal extraction groove 490f. Lead connection pieces 91a, 92a of the terminals 91, 92 are connected to the ends of the respective lead portions 32a, 32a. The terminals are embedded and integrated in the pedestal 490a, but they do not have to be embedded.

As shown in FIG. 3 , a first winding portion 45 is formed on the outer peripheral portion of the first hollow cylindrical portion 44 located between the bobbin upper collar portion 48 and the bobbin base plate 42 . In the first winding portion 45 , as shown in FIG. 6 , a plurality of winding partition ribs 46 separate adjacent wire winding portions along the winding axis (Z-axis) of the first wire 22 . It is formed integrally with the first hollow cylindrical portion 44 substantially parallel to the bobbin base plate 42 (and the bobbin upper collar portion 48) at predetermined intervals along the winding axis. The details of the winding partition brim 46 and the winding method of the first wire 22 will be described later.

The bobbin base plate 42, the first hollow cylindrical portion 44, the bobbin upper flange portion 48, and the wound partition wall flange 46 of the bobbin 40 are preferably integrally formed by injection molding or the like.

As shown in FIG. 3, a first through hole 44a is formed inside the first hollow cylindrical portion 44 of the bobbin substrate 42 so as to penetrate in the Z-axis direction. The middle leg 14 of the core 12 enters the first through-hole 44a from above and below in the Z-axis direction, and the tip of the middle leg 14 abuts against the substantially central portion of the through-hole 44a in the Z-axis direction. . A gap may be formed at a predetermined interval so that the tips of the middle legs 14 inserted from above and below in the Z-axis do not come into contact with each other at substantially the center of the through-hole 44a in the Z-axis direction.

As shown in FIG. 2C, the bobbin cover 50 is composed of a pair of half-split bodies 50a and 50b that can be split in the X-axis direction. , and in the combined state, the second winding portion 55 is formed on the outer peripheral portion of the cover 50 . As shown in FIG. 3, the bobbin cover 50 is attached to the outer periphery of the bobbin 40 after the first wire 22 is wound around the first winding portion 45 of the bobbin 40 to form the inner coil 20, and FIG. are combined at a split connection portion 53 shown in FIG.

As shown in FIG. 2C, the bobbin cover 50 has a second hollow cylindrical portion 54 that covers the inner coil 20 from the outside. 58 are formed along the circumferential direction at predetermined intervals in the Z-axis direction. The lower collar portion 52 and the upper collar portion 58 are provided parallel to the plane of the XY axis and extend parallel to the installation surface.

A second winding portion 55 is provided between the lower collar portion 52 and the upper collar portion 58, and the second wire 32 that constitutes the outer coil 30, which is, for example, a secondary coil, is attached to the second winding portion 55. Alignment winding (or α winding) is performed. Alignment winding is a normal winding method in which the wire is wound from one end of the winding shaft toward the other end. The α winding will be described later.

As shown in FIG. 2B, a pair of core covers 60 are attached from both sides in the Y-axis direction to the outer circumference of the bobbin cover 50 to which the outer coil 30 is attached. The core cover 60 is made of an insulating material such as synthetic resin, and has a cover body 62. Its outer peripheral surface serves as a guide surface for guiding the side legs 16 of the core 12, and its inner peripheral surface has an outer coil. 30 is located.

Mounting edges 64 , 64 are integrally formed at both ends of the cover body 62 in the Z-axis direction. The Z-axis upper mounting edge 64 is engaged with the upper surface of the bobbin upper collar portion 48 , the Z-axis lower mounting edge 64 is engaged with the lower surface of the bobbin substrate 42 , and the core cover 60 is attached to the bobbin 40 . .

The cover main body 62 has an inner peripheral surface shape corresponding to the outer peripheral surface shape of the core cover 60, and insulating plate portions 66 are integrally formed at both ends thereof in the X-axis direction. Engagement convex portions 66a projecting inward in the Y-axis direction are formed on the upper and lower sides of the insulating plate portion 66 in the Z-axis direction. The engagement projections 66a on the upper side of the Z-axis engage with the inner surface of the insulating wall 491e of the bobbin 40, and the engagement projections 66a on the lower side of the Z-axis engage the bobbin substrate 42 at both ends of the bobbin substrate 42 on the X-axis. Engage the lower surface.

As a result, as shown in FIG. 2E, the insulating plate portion 66 of the core cover 60 is combined with the insulating wall 491e and the bobbin substrate 42 to provide insulation between the core 12 shown in FIG. 2A and the outer coil 30 shown in FIG. 2E. Improve. The inner surface of the insulating plate portion 66 (on the center side of the coil device 10 ) may be in contact with the core 12 or may have a shape that matches the outer shape of the core 12 .

As shown in FIG. 3, in the present embodiment, an elliptical ring is formed so that winding sections 47 are formed at predetermined intervals along the Z-axis direction on the outer peripheral portion of a first hollow tubular portion 44 having a substantially elliptical tubular shape. A shaped wound bulkhead collar 46 is formed in a plane substantially parallel to the XY axis. In this embodiment, a plurality of winding partition ribs 46 are formed substantially parallel at predetermined intervals along the Z-axis direction, but the number is not particularly limited. The region where these winding partition ribs 46 are formed becomes the first winding portion 45 .

The winding section width along the winding axis (Z-axis) in each winding section 47 separated by the winding partition collar 46 is set to a width that allows only one wire 22 to enter. That is, the winding section width w1 and the wire diameter d1 of the wire 22 preferably satisfy d1<w1<(2×d1), more preferably d1<w1<(1.2×d1). is preferred. If the winding section width w1 is too wide with respect to the wire diameter d1, winding disorder is likely to occur, and it goes against the demand for a compact coil device.

In addition, in each winding section 47, the winding section width is preferably the same, but may be slightly different. Also, the winding section width between the bobbin upper collar 48 and the uppermost winding partition collar 46 may be greater than the winding section width between the winding partition collars 46 . Similarly, the winding section width between the bobbin substrate 42 and the lowest winding partition collar 46 may be greater than the winding section width between the winding partition collars 46 . In the present embodiment, the total number of turns to be wound around each winding section 47 is not particularly limited.

As shown in FIG. 2C, in the present embodiment, the winding partition rib 46 closest to the bobbin base plate 42 has a partition projection 46d that is inserted into the lower surface of the cover lower collar 52 of the bobbin cover 50 for positioning. It is intermittently formed in a part of the circumferential direction. As shown in FIG. 6A, except for the partition projection 46d, between the outer peripheral surface of the winding partition brim 46 and the inner peripheral surface of the bobbin cover 50, there is a flow gap 46e through which the highly thermally conductive resin can flow in the axial direction. is formed in a notched shape.

The partition projecting piece 46 d preferably protrudes from the outer peripheral surface of the winding partition brim 46 even at the position of the split connection portion 53 of the bobbin cover 50 . The projection height (radial height) of the partition projection piece 46d defines the radial width of the circulation gap 46e.

In the split connecting portion 53 of the bobbin cover 50, the outer connecting piece 53b of the other half 50b is inserted radially outwardly of the inner connecting piece 53a of one half 50a so that the half halves 50a and 50b are separated. are connected to form the bobbin cover 50 .

The bobbin cover 50 includes a second winding portion 54 around which a second wire 32 different from the first wire 22 is wound, and a non-removable portion provided below the second winding portion 54 along the axial direction. It has a gap holding piece 52a as a winding portion. The gap holding piece 52a as the non-wound portion has an opening 52b or a notch that allows the inside and outside of the bobbin cover 50 to communicate with each other. The gap holding piece 52a is formed to extend downward in the Z-axis direction from the outer peripheral edge of the cover lower flange, and the lower end thereof can abut on the upper surface of the bobbin substrate 42. As shown in FIG.

The openings 52b are formed in each of the half bodies 50a and 50b located on both sides in the X-axis direction, and are located at positions corresponding to the communication gaps 46e of the partition projections 46d provided on the winding partition brim 46 of the bobbin 40. formed. As shown in FIG. 2E , at the end in the X-axis direction, the gap holding piece 52 a is not formed on the outer peripheral edge of the cover lower brim portion 52 , and the gap between the cover lower brim portion 52 and the bobbin substrate 42 is not formed. A high thermal conductive resin or the like can enter freely through the gap.

In addition, as shown in FIG. 2C, a stepped connecting upper brim portion 58 positioned at the connecting portion 53a of one of the half bodies 50a has a stepped connecting upper brim portion that is higher along the Z axis than the other portions. A portion 58a is formed. In addition, the cover upper brim portion 58 positioned at the connection portion 53b of the other half 50b is positioned below the connection top brim portion 58a along the Z axis and is inserted under the connection top brim portion 58a. A connection upper brim portion 58b is formed which can be connected to the connector.

The cover upper brim portion 58 positioned at the connecting portion 53b of the other half 50b is formed with a stopper convex portion 58i with which the connection tip of the connection upper brim portion 58a can abut. The stopper protrusion 58i protrudes upward along the Z-axis from most of the upper surface of the cover upper collar portion 58 . It is preferable that the projection height of the stopper protrusion 58i relative to most of the upper surface of the cover upper brim portion 58 is substantially the same as the projection height of the connecting upper brim portion 58a along the Z-axis. The upper surface of the stopper convex portion 58i and the upper surface of the connection upper flange portion 58a contact the lower surface of the bobbin upper flange portion 48 of the bobbin 40, and the upper surface of most of the cover upper flange portion 58 other than the split connection portion 53 and the lower surface of the bobbin upper collar portion 48, an air outlet gap is formed.

An engaging projection projecting upward along the Z-axis from the upper surface of the cover upper brim portion 58 on the opposite side of the connection top brim portion 58a along the X-axis of the one half-split body 50a. A portion 58c is provided. An engaging surface 58e is formed on the upper surface of the engaging convex portion 58c, and the height of the protrusion of the engaging surface 58e with respect to the upper surface of the cover upper flange portion 58 along the Z-axis is equal to the step height of the connecting flange portion 58a. to the same extent. The engaging surface 58 e contacts the lower surface of the lead drawer base 491 . The lower surface of the lead drawer base 491 is substantially flush with the lower surface of the bobbin upper collar portion 48 along the Z-axis. A stepped protrusion 58g may be formed on the upper surface of the cover upper flange portion 58 located between the engaging portion 58c and the connection upper flange portion 58a. The step height of the step convex portion 58g is approximately the same as the step height of the connection collar portion 58a.

On the cover upper brim portion 58 on the opposite side of the connection upper brim portion 58b along the X axis of the other half-split body 50b, there is an engaging projection that protrudes upward along the Z axis from the upper surface of the cover top brim portion 58. A portion 58d is provided. An engaging surface 58f is formed on the upper surface of the engaging projection 58d, and the projection height of the engaging surface 58f with respect to the upper surface of the cover upper collar portion 58 along the Z-axis is equal to the projection height of the stopper projection 58i. to the same extent. The engaging surface 58 f contacts the lower surface of the lead drawer base 491 . The lower surface of the lead drawer base 491 is substantially flush with the lower surface of the bobbin upper collar portion 48 along the Z-axis. A step projection 58h may be formed on the upper surface of the cover upper flange portion 58 located between the engaging portion 58d and the stopper projection 58i. The step height of the step projection 58h is approximately the same as the step height of the stopper projection 58i.

The first wire 22 shown in FIG. 2C may be composed of a single wire or a stranded wire, preferably an insulated wire. The outer diameter d1 of the first wire 22 is not particularly limited, but is preferably φ1.0 to φ3.0 mm, for example, when a large current is applied. The second wire 32 may be the same as the first wire 22, but may be different.

In this embodiment an inner coil 20 of a first wire 22 constitutes the primary coil of the transformer and an outer coil 30 of a second wire 32 wound around a bobbin cover 50 constitutes the secondary coil. . Therefore, in this embodiment, as shown in FIG. 3, the wire diameter of the second wire 32 constituting the outer coil 30 is made larger than that of the first wire 22. However, the wire diameter is There is no particular limitation, and the wire diameters may be the same or may be different. Also, the materials of the first wire 22 and the second wire 32 may be the same or different.

As shown in FIG. 6, in the bobbin 40 of this embodiment, each winding partition flange 46 is formed with at least one communication groove 46a that connects adjacent winding sections 47 to each other. In this embodiment, the circumferential position of at least one of the pair of cutout edges 46b and 46c formed in the winding partition brim 46 so as to define the circumferential width of each communication groove 46a is aligned with the Z axis. The positions of the winding bulkhead collars 46 adjacent to each other along the direction (rolling axis) are different, but may be the same. Note that the circumferential direction is the direction along the elliptical outer peripheral surface of the hollow cylindrical portion 44 .

In this embodiment, as shown in FIG. 6, one cutout edge 46c of the pair of cutout edges 46b and 46c is uniformly inclined downward to the right, and the other cutout edge 46b is Except for the partition flange 46 where the partition projection 46d is formed, it is uniformly inclined downward to the right. The notch edge 46b is slanted in the opposite direction so that the circumferential width of the communication groove 46a is wider than the rest of the partition flange 46 formed with the partition projection 46d.

In the bobbin 40 of the present embodiment, the first wire 22 is α-wound, for example, from the central portion of the first winding portion 45 in the Z-axis direction. That is, the central portion 22b of the first wire 22 is arranged so as to pass through the communication groove 46a located in the central portion of the first winding portion 45 in the Z-axis direction, and the first wire 22 is directed from the central portion to the end. One of the lower winding portions 22c is passed through the winding section 47 one step below the center. Also, the other upper winding portion 22d of the first wire 22 is passed through the winding section 47 positioned one above the winding section 47 through which the lower winding portion 22c is passed, from the central portion toward the end.

After that, the lower winding portion 22c is wound one or more times in the same winding section 47 with a clockwise turn as viewed from the Z-axis, and the upper winding portion 22d is wound in the same winding section 47 in the upper stage, Z Turn one or more turns counterclockwise when viewed from the shaft. After that, the lower winding portion 22c moves from the wound winding section 47 through the connecting groove 46a to the winding section 47 one step lower in the Z-axis direction, and in the winding section 47, the winding section 47 also moves in the same direction. is wound on. Further, the upper winding portion 22d moves from the winding section 47 where it is wound, through the communication groove 46a, to the winding section 47 one step higher in the Z-axis direction, and in the winding section 47, in the same direction. be wound.

By repeating the operation, the first wire is α-wound around the first winding portion 45 . In this embodiment, the first winding portion 45 includes a first main winding portion 45a positioned between the partition projection 46d and the bobbin upper collar portion 48, and between the partition projection 46d and the bobbin substrate 42. It is divided into the positioned first sub-winding portion 45b. As shown in FIG. 3, in the first main winding portion 45a, the first wire 22 is α-wound in one or more layers in the radial direction. The first wire 22 is α-wound in a number of layers (first sub-winding layer number) larger than the radial number of winding layers (first main winding layer number) wound in the winding portion 45a. there is

Moreover, the position of the outermost layer of the first wire 22 wound around the first sub-winding portion 45b is located outside the cylindrical wall of the second winding portion 55. As shown in FIG. With this configuration, the flange-shaped coil portion 20a of the first wire 22 wound around the first sub-winding portion 45b and the outer coil of the second wire 32 wound around the second winding portion 55 30 overlap when viewed from the axial direction.

The lead portion 22a from the collar-shaped coil portion 20a located at the lowest end of the lower winding portion of the first wire 22 after α-winding shown in FIG. is drawn out of the bobbin cover 50 along the X-axis direction. The lead portion 22a drawn out of the bobbin cover 50 is raised upward in the Z-axis direction along the lead passage 240 of the insulating plate 200. As shown in FIG.

A lead passage 240 is formed between a pair of plate outward projecting pieces 230 formed in the plate body 210 . A plate top plate 220 is formed above the plate body 210 in the Z-axis direction. The plate top plate 220 is inserted and fixed between the lead drawer base 491 of the bobbin 20 and the engaging portion 58d of the bobbin cover 50 .

The lead portion 22 a raised upward in the Z-axis direction along the lead passage 240 of the insulating plate 200 is drawn out above the lead drawing portion 49 through the base drawing groove 491 a formed in the lead drawing base 491 . The lead portion 22a drawn upward from the lead drawing base 491 is passed through the vertical drawing groove 490e of the lead drawing block 490 shown in FIG. 2C. The lead lead-out portion 22 a passed through the vertical lead-out groove 490 e is led out along the horizontal lead-out groove 490 f of the block 490 to the outside in the Y-axis direction and connected to the lead connection piece 92 a of the terminal 92 .

2C, the lead portion 22a from the upper winding portion of the first wire 22 after α winding is passed through the other pedestal extraction groove 491c of the lead connection base 491, as shown in FIG. 2D. The lead portion 22a passed through the pedestal lead-out groove 491c is passed through the vertical lead-out groove 490e of the pedestal block 490 shown in FIG. 2C. The lead lead-out portion 22 a passed through the vertical lead-out groove 490 e is led out along the horizontal lead-out groove 490 f of the block 490 to the outside in the Y-axis direction and connected to the lead connection piece 91 a of the terminal 91 . In this embodiment, the "outer side" is the side away from the central axis of the bobbin 40, and the "inner side" is the side closer to the central axis of the bobbin.

On the other hand, as shown in FIG. 3 , in the bobbin cover 50 , the second wire 32 that constitutes the outer coil 30 serving as the secondary coil is wound in alignment around the second winding portion 55 thereof. Line winding is a winding method in which the wire 32 is sequentially wound from one end to the other end in the Z-axis direction around the outer peripheral surface of the winding portion 55. A layer or two or more layers are wound in alignment. If two layers are wound in an aligned manner, the first layer is entirely wound, and then the second layer is wound thereon.

Each lead portion 32a of the second wire 30, which constitutes the outer coil 30 shown in FIG. 2C, passes through the through groove formed in the engaging portion 58c of the bobbin cover 50 and the base pull-out groove of the lead pull-out base 491 shown in FIG. 2E. 491 c and pulled out above the lead drawer base 491 . The lead portions 32a, 32a drawn upward from the lead drawing base 491 are passed through the vertical drawing groove 490e of the base block 490 shown in FIG. 2E. The lead-out portions 22a, 22a passed through the vertical lead-out grooves 490e are led out along the horizontal lead-out grooves 490f, 490f of the block 490 to the outside on opposite sides in the Y-axis direction, respectively. are connected to the lead connection pieces 91a and 92a.

As shown in FIG. 2E, the lead-out portion 49 is composed of a lead-out block (terminal block) 490 and a lead-out block 491 , and the lead-out block 490 is provided with terminals 91 and 92 . In this embodiment, the terminals 91 and 92 are embedded and fixed (integrated) in the lead drawing block 490 by insert molding or the like, but they may be attached separately.

As shown in FIGS. 4A and 5A, terminals 91 and 92 have lead connection pieces 91a and 92a. Lead portions 22a, 22a of the inner coil 20 (first wire 22) or lead portions 32a, 32a of the outer coil 30 (second wire 32) shown in FIG. 2C are connected to the lead connection pieces 91a, 92a. As shown in FIGS. 4A and 5A, the lead connection pieces 91a and 92a have a substantially C-shape and sandwich the lead portions 22a and 22a or the lead portions 32a and 32a drawn outward in the Y-axis direction. do.

As shown in FIGS. 4A and 5A, side extending pieces 91b and 92b are integrally connected to the X-axis direction ends of the lead connection pieces 91a and 92a. The laterally extending pieces 91b and 92b extend outward in the Y-axis direction (direction away from the bobbin 40) when viewed from the lead connection pieces 91a and 92a, and extend in the same direction as the lead portion 22a. , 22a or the extending direction of the lead portions 32a, 32a.

As shown in FIGS. 4A and 5A, the ends of the laterally extending pieces 91b and 92b on the inside in the Y-axis direction (the side opposite to the side where the lead connecting pieces 91a and 92a are arranged) are provided with upwardly extending portions. The pieces 91c and 92c are integrally connected. The upwardly extending pieces 91 c and 92 c extend upward in the Z-axis direction and extend above the upper opening edge 330 of the case 300 . That is, part of the upwardly extending pieces 91 c and 92 c extends upwards from the upper opening edge 330 .

Case lateral pieces 91d and 92d are integrally connected to upper ends in the Z-axis direction of the upwardly extending pieces 91c and 92c. The case lateral pieces 91d, 92d extend outward from the center of the bobbin 40 along the X-axis direction. A step corresponding to the height of the upwardly extending pieces 91c, 92c is formed between the case lateral pieces 91d, 92d and the laterally extending pieces 91b, 92b. As shown in FIG. 3, the case lateral pieces 91d and 92d extend across the inside and outside of the case 300 along the X-axis direction, straddling (traversing) the upper opening edge 330 of the case 300. Alternatively, it extends from the inside of the case 300 to the outside above the upper opening edge 330 . The case lateral pieces 91d and 92d have a flat plate shape parallel to the XY plane, but may have a bent structure such as a curved surface.

As shown in FIGS. 4A and 5A, downward extending pieces 91e and 92e are integrally connected to the outer ends of the case lateral pieces 91d and 92d in the X-axis direction. The downwardly extending pieces 91e and 92e have flat plate shapes parallel to the YZ plane and extend downward in the Z-axis direction. The downwardly extending pieces 91e and 92e have a shape longer in the Z-axis direction than the upwardly extending pieces 91c and 92c, and as shown in FIG. ing.

The downwardly extending pieces 91e and 92e extend along the outer side surface 310 of the case 300 and extend downward from the upper opening edge 330 of the case 300 along the Z-axis direction.

As shown in FIGS. 4A and 5A, outward projecting pieces 91f and 92f are integrally connected to the lower ends of the downwardly extending pieces 91e and 92e in the Z-axis direction and inside in the Y-axis direction. . The outward projecting pieces 91f and 92f have a flat plate shape parallel to the XZ plane and extend in the X-axis direction. As shown in FIG. 3, the outward projecting pieces 91f and 92f extend away from the outer surface 310 of the case 300. As shown in FIG.

The distance in the Z-axis direction of the outwardly protruding pieces 91f and 92f from the upper opening edge 330 of the case 300 is determined according to the length in the Z-axis direction of the downwardly extending pieces 91e and 92e. is not limited to the example of , and may be set longer. In addition, in the present embodiment, the outward projecting pieces 91f and 92f have a flat plate shape parallel to the XZ plane. It may be in the form of a flat plate that extends along a plane between the .

As shown in FIG. 2E, the lead drawer pedestal 491 is formed integrally with the bobbin 40 and arranged at each end of the bobbin upper collar portion 48 of the bobbin 40 in the X-axis direction. An insulating wall 491 e is formed between the lead drawer base 491 and the bobbin upper flange 48 . The insulating wall 491 e has a flat plate shape parallel to the YZ plane and abuts on the insulating plate portion 66 of the core cover 60 . The position of the upper end of the insulating wall 491 e substantially coincides with the position of the upper end of the insulating plate portion 66 . The insulating wall 491e is provided to insulate the core 12 from the lead portions 32a (or 22a) of the outer coil 30 (or the inner coil 20) when the core 12 shown in FIG. 2A is attached to the bobbin 40. .

A fixing recess 491f recessed toward the center of the bobbin 40 is formed in the insulating wall 491e. The fixing recess 491f is arranged between each of the pair of insulating plate portions 66 of the core cover 60, and the fixing recess 491f and the insulating plate portion 66 are substantially flush with each other inside the insulating plate portion 66. placed in

A pedestal center portion 491a and two pedestal side portions 491b, 491b are formed at each end portion of the bobbin upper collar portion 48 in the X-axis direction. The pedestal central portion 491a and the pedestal side portion 491b have a shape in which the bobbin upper collar portion 48 is extended outward in the X-axis direction, and have a substantially flat plate shape parallel to the XY plane. The pedestal central portion 491a is arranged between each of the two pedestal side portions 491b, 491b.

A pedestal pull-out groove 491c is formed between one pedestal side portion 491b and the pedestal central portion 491a. Similarly, a pedestal pull-out groove 491c is formed between the other pedestal side portion 491b and the pedestal central portion 491a. The lead portion 32a (or 22a) of the outer coil 30 (or inner coil 20) can be inserted through the pedestal lead-out groove 491c. The pedestal extraction groove 491c extends along the X-axis direction.

A side thin plate portion 491d is formed at the outer end portion in the Y-axis direction of the base side portion 491b. The side thin plate portion 491d extends along the X-axis direction, and the thickness of the side thin plate portion 491d is thinner than the thickness of the base side portion 491b. A concave groove 490i of a lead drawing block 490, which will be described later, is engaged with the lateral thin plate portion 491d.

The lead drawing block 490 functions as a terminal base for fixing the terminals 91 and 92, and is formed separately from the bobbin 40 (the lead drawing base 491). For example, a resin different from that of the bobbin 40 can be washed as a material for the lead drawing block 490. For example, a resin with better moldability than the bobbin 40 or a resin with better heat dissipation can be selected. Specifically, for example, a resin material such as PET, PBK or PPS can be used.

As shown in FIG. 5A, the lead drawing block 490 has a pedestal 490a, and an engagement protrusion 490g is formed at substantially the center of the pedestal 490a in the Y-axis direction. The engagement protrusion 490g protrudes from the inner end of the base 490a in the X-axis direction toward the center of the bobbin.

Two front wall portions 490b, 490b are formed on the inner end surface of the base 490a in the X-axis direction so as to sandwich an engaging projection 490g therebetween. One front wall portion 490b is arranged on one side of the pedestal 490a in the Y-axis direction, and the other front wall portion 490b is arranged on the other side of the pedestal 490a in the Y-axis direction. The front wall portion 490b has a wall surface parallel to the YZ plane, and as shown in FIG. 2E, the front surface of the front wall portion 490b contacts the insulating wall 491e.

A fixing convex portion 490h is formed on the inner end surface of the front wall portion 490b. The fixing convex portion 490h is located on the inner end surface of the front wall portion 490b on the side where the engaging convex portion 490g is arranged. The inner end face of each fixing projection 490h formed on each front wall portion 490b abuts on each end in the Y-axis direction of a fixing recess 491f formed on the insulating wall 491e of the lead drawer base 491. FIG. As a result, when the lead drawing block 490 is attached to the lead drawing base 491 , it is possible to prevent the lead drawing block 490 from being displaced from the lead drawing base 491 in the Y-axis direction.

A vertical lead-out groove 490e is formed between the engaging projection 490g and one front wall portion 490b. Similarly, a vertical lead-out groove 490e is formed between the engaging projection 490g and the other front wall portion 490b. The vertical extraction groove 490e extends in the Z-axis direction, and the lead portion 32a (or 22a) of the outer coil 30 (or the inner coil 20) can be inserted along the vertical extraction groove 490e. The lead portion 32a (or 22a) is drawn upward in the Z-axis direction inside the vertical drawing groove 490e. That is, the vertical extraction groove 490e is aligned with the pedestal extraction groove 491c of the lead extraction base 491 and serves as a guide groove for guiding the lead portion 32a upward in the Z-axis direction.

A rear wall portion 490c extending from one side to the other side in the Y-axis direction is formed at the rear end (outer side of the bobbin) of the base 490a in the X-axis direction. As shown in FIG. 5A, two terminal holes 490j are formed in the rear wall portion 490c at predetermined intervals in the Y-axis direction. Case lateral pieces 91d, 92d of terminals 91, 92 are drawn out through respective terminal holes 490j.

A horizontal extraction groove 490f is formed between the rear wall portion 490c and the front wall portion 490b. The horizontal extraction groove 490f extends outward in the Y-axis direction, and the lead portion 32a (or 22a) of the outer coil 30 (or the inner coil 20) can be inserted along the horizontal extraction groove 490f. there is More specifically, the lead portion 32a drawn upward in the Z-axis direction along the vertical lead-out groove 490e is bent in the Y-axis direction and extends outward in the Y-axis direction along the horizontal lead-out groove 490f. pulled out toward That is, the horizontal extraction groove 490f functions as a guide groove that guides the lead portion 32a (or 22a) outward in the Y-axis direction.

A side wall portion 490d is formed at each end of the base 490a in the Y-axis direction. The side wall portion 490d has a wall surface parallel to the XZ plane and extends downward in the Z-axis direction from the base 490a. The terminal hole 490j described above communicates with the side wall portion 490d, and the laterally extending pieces 91b and 92b of the terminals 91 and 92 are pulled out through the terminal hole 490j.

A concave groove 490i is formed in the side wall portion 490d. The groove 490i is formed inside the side wall portion 490d in the Y-axis direction and extends along the X-axis direction. The side thin plate portion 491d (see FIG. 2E) of the lead drawer base 491 is slidably inserted into the concave groove 490i, and the concave groove 490i and the side thin plate portion 491d are engaged. As a result, the lead drawer base 491 is engaged with the lead drawer block 490 , and the lead drawer block 490 can be fixed to the lead drawer base 491 . Note that the side wall portion 490d may be formed so as to extend below the resin upper surface LS of the high thermal conductive resin filled inside the case 300 shown in FIG. In that case, the block 490 is in contact with the high thermal conductive resin filling the inside of the case 300 so that heat can be dissipated.

As shown in FIGS. 4A and 5A, the insulation protector 100 has an inner extension portion 110, a case crossing portion 120, and an outer extension portion . The insulating protection portion 100 is interposed between the terminals 91 and 92 and the case 300 to insulate the terminals 91 and 92 from the case 300 (see FIG. 3). In this embodiment, the insulating protection part 100 is formed separately from the lead drawing block 490 and is detachably held or fixed to the case 300 .

The insulating protection portion 100 is made of an insulating material. Materials constituting the insulation protection part 100 include polyimide-based resin, silicone-based resin, epoxy-based resin, acrylic-based resin, polyetheretherketone-based resin, polyethersulfone-based resin, polyacetal-based resin, aromatic polyamide-based resin, and the like. In addition to this, a resin or other member having heat resistance (or elasticity) in addition to insulation may be used.

The insulating protection portion 100 has a thin plate (flat plate) shape and is substantially C-shaped. As shown in FIG. 3 , the insulation protector 100 is attached to the case 300 so as to straddle the outer side surface 310 , the inner side surface 320 and the upper opening edge 330 of the case 300 . The thickness of the insulation protection portion 100 is preferably 0.5 to 1.0 mm. However, the thickness of the insulating protection portion 100 is not limited to the thickness described above, and the insulation between the terminals 91 and 92 arranged on the front surface thereof and the case 300 arranged on the rear surface thereof can be effectively secured. It can be determined appropriately within the range. The width of the insulating protection portion 100 in the Y-axis direction is larger than the distance between the terminals 91 and 92 in the Y-axis direction.

As shown in FIGS. 3 and 5A, the inner extension 110 has a flat plate shape parallel to the YZ plane and extends along the inner surface 320 of the case 300. As shown in FIG. The inner extending portion 110 abuts the inner side surface 320 of the case 300 . The length of the inner extending portion 110 in the Z-axis direction is appropriately determined within a range in which the insulation protection portion 100 can be reliably held (hooked) on the upper opening edge 330 of the case 300 . As shown in FIG. 3 , the inner extending portion 110 is preferably formed to extend below the resin upper surface LS of the high thermal conductive resin housed inside the case 300 .

A case crossing portion 120 is integrally connected to the upper end of the inner extending portion 110 in the Z-axis direction. The case crossing portion 120 extends along the X-axis direction in a direction away from the bobbin 40 (outside the bobbin 40). The case crossing portion 120 extends across the inside and outside of the case 300 along the X-axis direction, straddling (traversing or overcoming) the upper opening edge 330 of the case 300 and The upper surface of 330 extends from the inside of case 300 toward the outside.

The case crossing portion 120 has a flat plate shape parallel to the XY plane and abuts the upper opening edge 330 of the case 300 . The case cross section 120 and the case cross sections 91d, 92d of the terminals 91, 92 face each other. The length of the case crossing portion 120 in the X-axis direction is substantially equal to the length of the upper opening edge 330 of the case 300 in the X-axis direction. In the example shown in FIG. 3, a predetermined gap is formed between the case transverse portion 120 and the case transverse pieces 91d and 92d of the terminals 91 and 92, but they may be in contact with each other.

An outer extending portion 130 is integrally connected to the outer end portion of the case crossing portion 120 in the X-axis direction. The outer extending portion 130 has a flat plate shape parallel to the YZ plane and extends downward in the Z-axis direction. Outer extending portion 130 abuts on outer side surface 310 of case 300 . The outer extending portion 130 has a shape longer in the Z-axis direction than the inner extending portion 110 and extends downward from the case crossing portion 120 along the outer surface 310 of the case 300 .

The outer extending portion 130 faces downward extending pieces 91 e and 92 e of the terminals 91 and 92 . In the example shown in FIG. 3, a predetermined gap is formed between the outer extending portion 130 and the downward extending pieces 91e and 92e, but they may be in contact with each other.

The lower end of the outer extending portion 130 in the Z-axis direction is arranged at a position lower in the Z-axis direction than the lower ends of the downwardly extending pieces 91e and 92e of the terminals 91 and 92 in the Z-axis direction. As a result, insulation between the downward extending pieces 91 e and 92 e and the outer surface 310 of the case 300 can be ensured through the outer extending portion 130 .

In the present embodiment, the upper portion of the case 300 where the terminals 91 and 92 are exposed from the lead drawing portion 49 (the lead drawing block 490) is covered with the case crossing portion 120 and the outer extension portion 130 of the insulating protection portion 100. It is possible to form an insulating region in this portion.

The coil device 10 according to this embodiment is manufactured by assembling members shown in FIGS. The coil device 10 of this embodiment is housed inside the case 300, but the case 300 may not necessarily be provided.

An example of a method for manufacturing the coil device 10 will be described below. In manufacturing the coil device 10, first, a bobbin 40 shown in FIG. 2C is prepared. Although the material of the bobbin 40 is not particularly limited, the bobbin 40 is made of an insulating material such as resin.

Next, the first wire 22 is wound around the outer periphery of the first hollow cylindrical portion 44 of the bobbin 40 to form the inner coil 20 . Although the first wire 22 used to form the inner coil 20 is not particularly limited, a litz wire or the like is preferably used. In the inner coil 20, a brim-shaped coil portion 20a having an outer diameter larger than that of other portions of the inner coil 20 is formed at the Z-axis lower end of the inner coil portion 20 by α winding.

Next, the bobbin cover 50 is attached to the bobbin 40 on which the inner coil 20 is formed. A second wire 32 forming the outer coil 30 is wound around the outer circumference of the second hollow cylindrical portion 54 of the bobbin cover 50 . The brim-shaped coil portion 20a is positioned inside the clearance holding piece 52a of the cover lower brim portion 52 of the bobbin cover 50. As shown in FIG. That is, the first sub-winding portion 45b shown in FIG.

The lead portions 22a and 32a are passed through the pedestal extraction groove 491c of the lead connection base 491, and then the lead extraction blocks 490 and 490 are attached to the pedestals 491 by sliding from the outside in the X-axis direction.

After that, the core covers 60 shown in FIG. 2C are attached to both sides of the bobbin cover 50 in the Y-axis direction, and then the core 12 is attached from above and below in the Z-axis direction. That is, the tips of the middle legs 14 and 14 of the core 12 and the tips of the side legs 16 and 16 are butted against each other. A gap may be provided between the tips of the middle legs 14 , 14 .

The material of each core 12 includes, but is not particularly limited to, soft magnetic materials such as metal and ferrite. The core 12 may be fixed to the bobbin cover 50 and the bobbin 40 by bonding with an adhesive or by winding the outer periphery with a tape-shaped member, or may be simply attached. In this embodiment, most of the coil device 10 assembled in this way is housed inside the case 300 as shown in FIG.

As shown in FIG. 3, the interior of the case 300 is filled with high thermal conductivity resin such as potting resin up to the resin upper surface LS while the coil device 10 is housed therein. The position of the resin upper surface LS is preferably located below the upper opening edge 330 of the case 300 in the Z-axis direction and near the lower surface of the bobbin upper collar 48 of the bobbin 40 . A gap in the Z-axis direction between the resin upper surface LS and the upper opening edge 330 of the case 300 is preferably 3 mm to 10 mm.

A radiation plate 80 may be arranged on the core 12 so as to be in contact with the upper surface of the core 12 and the side surface in the Y-axis direction. The part is immersed in the highly conductive resin stored inside the case 300 . With this configuration, the heat of the upper portion of the core 12 is transferred to the high thermal conductive resin stored inside the case 300, so that the heat can be efficiently dissipated. The heat sink plate 80 is preferably made of a highly thermally conductive material such as metal such as aluminum.

The high thermal conductivity resin is preferably filled into the case 300 before the coil device 10 is housed inside the case, but the resin may be filled after the coil device 10 is housed inside the case.

Since the coil device 10 of the present embodiment can be used as a vertical type coil device in which the winding axis of the coil is arranged perpendicular to the surface of the mounting board, the core 12 inserted into the hollow portion of the bobbin 40 is Easy to cool.

Furthermore, in this embodiment, the bobbin cover 50 can be split at the split connection portion 53 parallel to the winding axis, as shown in FIG. can be done.

As shown in FIG. 3, in the coil device 10 of the present embodiment, the wire 22 is wound so that only a single wire winding portion exists along the winding axis direction in each winding section 47. , it becomes easy to prevent variations in the number of turns of the wire 22 per layer in the radial direction, contributing to stabilization of leakage characteristics (coupling between coils). That is, it becomes easy to strictly control the coupling coefficient between the outer coil 30 forming the secondary coil and the inner coil 20 forming the primary coil. be able to.

Further, in the present embodiment, as shown in FIG. 2C, gap holding pieces 52a are intermittently provided at the outer edge of the cover lower collar portion 52 of the bobbin cover 50. As shown in FIG. For this reason, as shown in FIG. 3, it becomes easy to form the brim-shaped coil portion 20a having a large number of wound layers in the radial direction at the lower end portion of the first coil 20 in the Z-axis direction.

Furthermore, in this embodiment, as shown in FIG. 2D, an insulating plate 200 is attached to one end of the bobbin cover 50 in the X-axis direction. For this purpose, the lead portion 22a on the lower side of the first wire 22 constituting the inner coil 20 is taken out from under the cover lower collar portion 52 of the cover 50, and insulation from the outer coil 30 is ensured, and the lead extraction table is placed. It is easy to lead to 491.

Further, in this embodiment, as shown in FIG. 3 , a uniform flow gap is formed between the outer peripheral edge of the winding partition brim 46 and the inner peripheral surface of the bobbin cover 50 . By configuring in this way, the distance between the coils 20 and 30 of the wire wound inside and outside the bobbin cover 50 can be easily made constant, and variations in coil characteristic values can be reduced.

In particular, in the coil device 10 according to the present embodiment, as shown in FIG. 2C, the bobbin cover 50 has a gap holding piece 52a, and the gap holding piece 52a has an opening 52b or a notch. For this reason, a high thermal conductive resin such as potting resin enters inside the bobbin cover 50 and enters between the bobbin cover 50 and the bobbin 40 through the opening 52b or the notch. As a result, the first wire 22 wound around the first winding portion 45 of the bobbin 40 comes into contact with the highly thermally conductive resin, and the heat generated from the first wire 22 is transmitted to the highly thermally conductive resin and is dissipated satisfactorily. be. Therefore, the coil device 10 of the present embodiment is excellent in heat dissipation even when the coil device 10 is downsized.

In addition, in the present embodiment, the bobbin cover 50 has a cover lower flange portion 52 and a cover upper flange portion 58, as shown in FIG. 2C. A clearance retaining piece 52a is provided below the cover lower collar portion 52. As shown in FIG. Further, a cover upper brim portion 58 is arranged below the bobbin upper brim portion 48 in the axial direction, and between the bobbin top brim portion 48 and the cover upper brim portion 58, the air inside the bobbin cover 50 is released to the outside. A drainable exit gap is formed. The outlet gap is formed by contacting the lower surface of the bobbin upper flange 48 with the connection upper flange 58a, the step projections 58g and 58h, and the stopper projection 58i formed on the upper surface of the cover upper flange 58. .

By configuring in this way, when the high thermal conductive resin enters the inside of the bobbin cover 50 from below the cover lower collar portion 52, the air located inside the bobbin cover 50 can be easily discharged from the outlet gap. , the resin flow becomes smoother.

Furthermore, in this embodiment, the first wire 22 arranged on the inner peripheral side is the primary coil of the transformer, but conversely, it may be the secondary coil (inner coil 20) on which a higher voltage acts. . In this case, the secondary coil (inner coil 20) to which a high voltage acts is arranged inside the primary coil (outer coil 30) to which a relatively low voltage acts, thereby facilitating insulation.

Furthermore, in the coil device 10 according to this embodiment, the terminals 91 and 92 have case lateral pieces 91d and 92d and downwardly extending pieces 91e and 92e. Therefore, the terminals 91 and 92 do not extend above the case 300 but on the side of the case 300 (in the direction along which the case lateral pieces 91d and 92d extend), and the terminals 91 and 92 are fixed above the case 300. There is no need to provide a terminal block (lead drawing block 490) for connecting. Therefore, most of the coils 20, 30 and the core 12 can be accommodated inside the case 300, and by filling the case 300 with resin for heat dissipation (high thermal conductivity resin), the coils 20, 30 and A large part of the core 12 is immersed in heat-radiating resin, and heat generated by the coils 20 and 30 and the core 12 can be sufficiently radiated through the heat-radiating resin.

In addition, in the coil device 10 according to the present embodiment, as described above, since it is not necessary to provide a terminal block (lead drawing block 490) above the case 300, the height of the coil device 10 can be reduced. The height of the coil device 10 can be reduced.

Further, in the coil device 10 according to the present embodiment, the terminals 91 and 92 are provided with the downward extending pieces 91e and 92e. There is no need to pull out outside 300 downward. Therefore, when the case 300 is filled with the heat-dissipating resin, the case 300 is filled with a sufficient amount of the heat-dissipating resin, and the case 300 is filled with a sufficient amount of the heat-dissipating resin. Heat generated by the coils 20 and 30 and the core 12 can be efficiently dissipated through the heat dissipating resin.

Moreover, in this embodiment, the terminals 91 and 92 have outward projecting pieces 91f and 92f. Therefore, the outward projecting pieces 91f and 92f can be used as user terminals.

Further, the coil device 10 according to this embodiment has an insulation protection portion 100 . Therefore, the terminals 91 and 92 can be pulled out to the side of the case 300 through the insulating protection portion 100 while preventing short-circuit failure between the terminals 91 and 92 and the case 300 .

In addition, in this embodiment, the insulation protection portion 100 has a case crossing portion 120 and an outer extension portion 130 . Therefore, the terminals 91 and 92 are insulated from the upper opening edge 330 of the case 300 via the case transverse portion 120, and the terminals 91 and 92 are insulated from the outer surface 310 of the case 300 via the outer extending portion 130. can be done.

Further, in this embodiment, the lead drawing block 490 is provided, and the insulating protection part 100 is formed separately from the lead drawing block 490 . Therefore, it is possible to simplify the structure of the lead drawing block 490 or the insulating protection part 100, and the lead drawing block 490 or the insulating protection part 100 can be easily formed.

Also, in this embodiment, the lead drawing block 490 is formed separately from the bobbin 40 . Therefore, if the specifications of the lead drawing block 490 are changed, a lead drawing block 490 that conforms to the specifications may be prepared and attached to the bobbin 40 . That is, there is no need to change the design of the entire bobbin, and it is possible to flexibly respond to changes in specifications.

Further, as shown in FIG. 3, in the coil device 10 of the present embodiment, the inner coil portion 20 of the first wire 22 wound around the first main winding portion 45a and the second winding portion 55 wound around the inner coil portion 20 Coupling between the coils can be adjusted by the radial clearance between the second wire 32 and the outer coil portion 30 . Furthermore, in the coil device 10 of the present embodiment, the flange-shaped coil portion 20a of the first wire 22 wound around the first sub-winding portion 45b and the second wire 32 wound around the second winding portion 55 Coupling between the coils can be adjusted also by the gap in the Z-axis direction between the outer coil portion.

Further, if the number of winding layers of the first wire 22 wound around the first sub-winding portion 45b is increased, the overlapping area between the brim-shaped coil portion 20a and the outer coil portion 30 when viewed from the axial direction also increases. , leakage characteristics can be adjusted. As described above, in the coil device 10 of the present embodiment, it is possible to adjust the leakage characteristics in both the radial clearance and the axial clearance.

Further, in the coil device 10 of the present embodiment, by increasing the number of winding layers of the first wire 22 wound around the first sub-winding portion 45b of the first winding portion 45, the first wire 22 is Since the total number of turns can be increased, the axial dimension of the bobbin 40 can be shortened. Therefore, it is possible to reduce the height of the coil device 10 .

Furthermore, in the present embodiment, the position of the outermost layer of the brim-shaped coil portion 20 a wound around the first sub-winding portion 45 b is located outside the cylinder wall of the second winding portion 55 . With this configuration, the brim-shaped coil portion 20a and the outer coil portion 30 overlap each other when viewed from the axial direction. Therefore, the gap between the collar-shaped coil portion 20a of the first wire 22 wound around the first sub-winding portion 45b and the outer coil portion 30 of the second wire 32 wound around the second winding portion 55 is The clearance in the axial direction facilitates adjustment of leakage characteristics.

Further, in the present embodiment, winding partition ribs 46 are formed on the first winding portion 45 at predetermined intervals along the Z-axis direction. By configuring in this way, the α-winding of the first wire 22 is facilitated. In addition, on the winding partition brim 46 that separates the first main winding portion 45a and the first sub-winding portion 45b, the outer edge of the winding partition brim 46 formed within the range of the first main winding portion 45a A partition projection piece 46d (see FIG. 2C) is formed as a projection projecting outward from the end. This partition projection piece 46 d can also function as positioning with the bobbin cover 50 .

Further, in the present embodiment, gap holding pieces 52a are intermittently formed along the circumferential direction on the outer peripheral edge of the cover lower collar portion 52 of the bobbin cover 50, and inside the gap holding pieces 52a, the first sub The winding portion 45b is positioned to form the brim-shaped coil portion 20a. By configuring in this way, it becomes easy to wind the first wire 22 around the outer periphery of the first sub-winding portion 45b with a large number of turns.

Further, in the present embodiment, the first wire 22 is continuously α-wound around the first main winding portion 45a and the first sub-winding portion 45b. The α-winding facilitates the winding of the first wire 22 and reduces the axial length of the inner coil 20 formed by the first wire 22 . Moreover, it is easy to wind the first wire 22 in many turns around the outer periphery of the first sub-winding portion 45b.

Second embodiment

A coil device 10A according to the second embodiment shown in FIGS. 1B and 5B has a configuration similar to that of the coil device 10 according to the first embodiment, except for the points described below, and has similar effects. In FIGS. 1B and 5B, members common to each member in the coil device 10 of the first embodiment are denoted by common reference numerals, and description thereof is partially omitted.

10 A of coil apparatuses in this embodiment have 100 A of insulation protection parts. 5A and 5B, the insulation protection portion 100A in this embodiment differs from the insulation protection portion 100 in the first embodiment in that it is formed integrally with the lead drawing block 490. different. The insulating protection portion 100A and the lead drawing block 490 are integrally formed by injection molding or the like.

As shown in FIG. 5B, the insulating protection portion 100A has a case crossing portion 120A and an outer extending portion 130A, and has a substantially L-shaped shape. On the other hand, the insulation protection portion 100A does not have a configuration corresponding to the inner extension portion 110 in the first embodiment shown in FIG. 5A. In the present embodiment, as shown in FIG. 5B, the insulation protection portion 100A is integrated with the lead drawing block 490, so that the rear wall portion 490c of the lead drawing block 490 becomes the inner extending portion 110 shown in FIG. 5A. play a similar role.

As shown in FIG. 5B, the case transverse portion 120A is formed thicker than the case transverse portion 120 in the first embodiment shown in FIG. ing. That is, in this embodiment, the case lateral pieces 91d and 92d are not exposed to the outside but are embedded inside the case crossing portion 120A. The inner end of the case crossing portion 120A in the X-axis direction is integrally connected to the upper end of the rear wall portion 490c of the lead drawing block 490 in the Z-axis direction. The lower surface of the case crossing portion 120A contacts the upper opening edge 330 of the case 300. As shown in FIG.

The outer extending portion 130A is formed thicker than the outer extending portion 130 in the first embodiment shown in FIG. 5A, and accommodates the downward extending pieces 91e and 92e of the terminals 91 and 92 therein. That is, in this embodiment, the downwardly extending pieces 91e and 92e are not exposed to the outside but are embedded inside the outer extending portion 130A. Two terminal holes 131, 131 are formed in the X-axis direction outer end face of the outer extension portion 130A at a predetermined interval in the Y-axis direction. Outward projecting pieces 91f and 92f of the terminals 91 and 92 are pulled out through the terminal holes 131 and 131, respectively. The inner end face in the X-axis direction of the outer extension portion 130A contacts the outer side surface 310 of the case 300 .

The insulation protection portion 100A is attached to the case 300 so that the upper end portion of the case 300 is sandwiched between the outer extension portion 130A and the rear wall portion 490c of the lead drawing block 490. As shown in FIG.

Also in this embodiment, the same effect as in the first embodiment can be obtained. In addition, in this embodiment, the insulating protection portion 100A is integrally formed with the lead drawing block 490. As shown in FIG. Therefore, in the manufacturing process of the coil device 10A, it is possible to omit the process of attaching the insulating protection portion 100A separately (as a single unit) to the case 300, which facilitates the manufacturing of the coil device 10A.

Moreover, in this embodiment, the insulating protection portion 100A is formed integrally with the terminals 91 and 92 . For example, the coil device 10A can be easily manufactured by integrally molding the terminals 91 and 92 with the insulating protection portion 100A by insert molding or the like.

The present invention is not limited to the embodiments described above, and various modifications can be made within the scope of the present invention.

For example, in the above-described embodiment, as shown in FIG. 3, the first sub-winding portion 45b is formed below the first main winding portion 45a in the Z-axis direction, and the collar-shaped coil portion 20a is the inner coil 20. is formed on the lower side of the , but the opposite is also possible. That is, the first sub-winding portion 45b may be formed above the first main winding portion 45a in the Z-axis direction, and the brim-shaped coil portion 20a may be formed above the inner coil 20. FIG. However, in the present embodiment, since cooling is performed from the lower side of the case 300, heat dissipation is better when the brim-shaped coil portion 20a, which has a larger number of wound layers in the radial direction, is located on the lower side.

Further, the first wire 22 does not need to be α-wound, and may be aligned-wound. The effects of the present invention can be expected even with regular winding. Furthermore, the specific shape of the bobbins 40, 40a or the specific shape of the core 12 is not limited to the above-described embodiment, and can be variously modified. In addition, the coil device of the present invention can also be used for reactors and the like as applications other than transformers for chargers, for example.

In each of the above embodiments, the shape of the insulating protection portions 100 and 100A may be changed as appropriate. For example, in FIG. 5A, the inner extending portion 100 may be omitted from the insulating protecting portion 100, and the insulating protecting portion 100 including the case crossing portion 110 and the outer extending portion 130 may be configured. Also, in FIG. 5B, the insulating protection portion 100A and the lead drawing block 490 may be separated.

In each of the above embodiments, the two insulation protection portions 100 and 100A are provided in the coil devices 10 and 10A, one insulation protection portion 100 and 100A insulates the terminal 91 and the case 300, and the other insulation protection portion 100 , 100A may be used to insulate the terminal 92 and the case 300 from each other.

In this case, the shape of the insulation protection portions 100, 100A may be substantially the same as the shape of the case lateral pieces 91d, 92d and the downwardly extending pieces 91e, 92e of the terminals 91, 92.

DESCRIPTION OF SYMBOLS 10, 10A... Coil apparatus 12... Core 13... Base 14... Middle leg 16... Side leg 20... Inner coil 20a... Flanged coil part 22... First wire 22a... Lead part 30... Outer coil 32... Second wire 32a... Lead part 40... Bobbin 42... Bobbin substrate 42a... Leg part 44... First hollow cylindrical part 44a... First through hole 44b... Separation convex part 45... First winding part 45a... First main winding part 45b... Third 1 sub-winding part 46... Winding partition flange 46a... Communication groove 46b, 46c... Notch edge part 46d... Partition convex piece (convex part)
46e... Distribution gap 47... Winding section 48... Bobbin upper flange 48a... Stepped portion 48b... Positioning concave portion 48c... Engagement convex portion 49... Lead drawer 490... Lead drawer block (terminal block)
490a Pedestal 490b Front wall portion 490c Rear wall portion 490d Side wall portion 490e Vertical lead-out groove 490f Horizontal lead-out groove 490g Engagement protrusion 490h Fixing protrusion 490i Groove 491 Lead drawer base 491a Pedestal central portion 491b Pedestal side portion 491c Pedestal pull-out groove 491d Side thin plate portion 491e Insulating wall 491f Fixing concave portion 50 Bobbin cover 50a, 50b Half-split body 52 Cover lower collar portion 52a Gap retaining piece (non-wound part)
52b... Opening 53... Split connection part 53a... Inner connection piece 53b... Outer connection piece 54... Second hollow cylindrical part 55... Second winding part 58... Cover upper brim part 58a... Connection upper brim part 58b... Connection lower brim part Part 58c, 58d Engagement portion 58e, 58f Engagement surface 58g, 58h Step projection 58i Stopper projection 60 Core cover 62 Cover body 62a Split piece 64 Mounting edge 64a Protruding piece 64b Opening Part 66... Insulating plate part 66a... Engagement convex part 70... Lead drawer block cover 71... Top plate part 72... Side wall part 73... Rear wall part 74... Recessed part 80... Radiation plate 91, 92... Terminals 91a, 92a... Lead connecting pieces 91b, 92b... Lateral extending pieces 91c, 92c... Upward extending pieces 91d, 92d... Case lateral pieces 91e, 92e... Downward extending pieces 91f, 92f... Outwardly projecting pieces 100, 100A... Insulation protection part DESCRIPTION OF SYMBOLS 110... Inside extension part 120, 120A... Case crossing part 130, 130A... Outside extension part 200... Insulating plate 210... Plate main body 220... Plate top plate 230... Plate outward protrusion piece 240... Lead path 300... Case 305... Frame body 310 Outer surface 320 Inner surface 315, 330 Opening edge 340 Bottom plate LS Upper surface of resin

Claims (9)

a bobbin having a first winding portion around which a first wire is wound;
A coil device comprising a bobbin cover that covers the bobbin around which the first wire is wound,
The bobbin cover includes a second winding portion around which a second wire different from the first wire is wound, and a position below or above the second winding portion along the axial direction. and a non-wound portion;
Compared to the number of main winding layers of the first wire wound around the first main winding portion of the first winding portion located inside the second winding portion, the number of the non-winding portions is A coil device, wherein the number of sub-winding layers of the first wire wound on the first sub-winding portion of the first winding portion positioned inside is large. 2. The coil device according to claim 1, wherein the outermost layer of the first wire wound around the first sub-winding portion is located outside the cylindrical wall of the second winding portion. the first wire wound around the first sub-winding portion;
and the second wire wound around the second winding part,
The coil device according to claim 1 or 2, wherein the coil devices are overlapped when viewed from the axial direction. In the first winding portion, winding partition ribs are formed at predetermined intervals along the axial direction,
The winding partition brim that separates the first main winding portion and the first sub-winding portion has a larger diameter than the outer edge of the winding partition brim formed within the range of the first main winding portion. 4. The coil device according to any one of claims 1 to 3, wherein a convex portion protruding outward is formed. 5. The coil device according to claim 4, wherein the protrusion has a notch forming a flow gap penetrating in the axial direction. The bobbin cover is
a second hollow cylindrical portion constituting the second winding portion;
a pair of cover brim portions formed at both ends of the second hollow cylindrical portion in the axial direction;
A plurality of gap holding pieces constituting the non-wound portion are intermittently formed along the circumferential direction on the outer periphery of at least one of the cover flange portions,
The coil device according to any one of claims 1 to 5, wherein the first sub-winding portion is positioned inside the gap holding piece. 7. The coil device according to claim 6, wherein the gap holding piece is formed with an opening connecting the outside and the inside of the gap holding piece. The coil device according to any one of claims 1 to 7, wherein the first wire is α-wound around the first main winding portion and the first sub-winding portion. 9. The method according to any one of claims 1 to 8, further comprising a case containing said high thermal conductive resin such that the first winding portion of said bobbin and the second winding portion of said bobbin cover are filled with said high thermal conductive resin. A coil device according to any one of the preceding claims.

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