Coil device

Abstract

The present invention provides a coil device that can easily adjust leakage characteristics and can be made thinner. The coil device comprises: a bobbin (40) having a first winding portion (45) for winding a first winding (22) around the outer periphery; and a bobbin cover (50) for covering the periphery of the bobbin (40) around which the first winding (22) is wound. The bobbin cover (50) comprises a second winding portion (55) for winding a second winding (32) different from the first winding (22) around the outer periphery, and a non-winding portion arranged at a lower position or an upper position along the axial direction of the second winding portion (55), wherein the number of sub-winding layers of the first winding (22) wound on a first sub-winding portion (45b) of the first winding portion (45) located inside the non-winding portion is greater than the number of main winding layers of the first winding (22) wound on a first main winding portion (45a) of the first winding portion (45) located inside the second winding portion (55).

Description

Technical Field

[0001] The present invention relates to a coil device which can also be suitably used as, for example, a transformer. Background Art

[0002] As a coil device for a transformer, for example, there is known a coil device as shown in Patent Document 1. In this conventional coil device, the inner coil is wound around the outer peripheral surface of a bobbin arranged inside, which is surrounded by a bobbin cover, and the outer coil is wound around the outer periphery.

[0003] In such a coil device, the coupling between the outer coil and the inner coil is generally adjusted (for example, the leakage characteristic is adjusted) by shifting the axial positions of the inner coil and the outer coil.

[0004] However, it is difficult to reduce the height of the coil device by simply adjusting the coupling between the coils by shifting the axial positions of the inner coil and the outer coil as in the conventional method.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent No. 6268509 Summary of the invention

[0008] Problems to be solved by the invention

[0009] The present invention has been made in view of such actual conditions, and an object of the present invention is to provide a coil device that can easily adjust the coupling between coils and can be made thinner.

[0010] Technical solutions to solve problems

[0011] In order to achieve the above object, the present invention provides a coil device having:

[0012] a bobbin having a first winding portion for winding a first winding wire around an outer circumference;

[0013] A bobbin cover covering the periphery of the bobbin around which the first winding wire is wound, characterized in that:

[0014] The bobbin cover includes a second winding portion for winding a second winding wire different from the first winding wire around an outer circumference, and a non-winding portion arranged at a lower position or an upper position along an axial direction of the second winding portion.

[0015] The number of sub-winding layers of the first winding wound in the first sub-winding portion of the first winding portion located inside the non-winding portion is greater than the number of main winding layers of the first winding wound in the first main winding portion of the first winding portion located inside the second winding portion.

[0016] In the coil device of the present invention, the inter-coil coupling can be adjusted (for example, the leakage characteristic can be adjusted) by the radial gap between the first winding wound on the first main winding portion and the second winding wound on the second winding portion. Moreover, in the coil device of the present invention, the inter-coil coupling can also be adjusted by the axial gap between the first winding wound on the first sub-winding portion and the second winding wound on the second winding portion. In addition, if the number of winding layers of the first winding wound on the first sub-winding portion is increased, the overlapping area of ​​the first winding and the second winding observed from the axial direction is also increased, and the inter-coil coupling can be adjusted. In this way, in the coil device of the present invention, the inter-coil coupling can be easily adjusted by both the radial gap and the axial gap.

[0017] In addition, in the coil device of the present invention, by increasing the number of winding layers of the first winding wound on the first sub-winding portion of the first winding portion, the total number of turns of the first winding can be increased, thereby shortening the axial dimension of the bobbin. Therefore, the height of the coil device can be reduced.

[0018] Preferably, the outermost peripheral layer of the first winding wound on the first sub-winding portion is located outside the barrel wall of the second winding portion. By configuring in this way, the wound first winding and the wound second winding overlap when viewed from the axial direction. Therefore, the axial gap between the first winding wound on the first sub-winding portion and the second winding wound on the second winding portion makes it easy to adjust the coupling between the coils.

[0019] Preferably, when viewed from the axial direction, the first winding wound on the first sub-winding portion and the second winding wound on the second winding portion overlap. With such a configuration, the coupling between the coils can be easily adjusted by the axial gap between the first winding wound on the first sub-winding portion and the second winding wound on the second winding portion.

[0020] Preferably, a winding partition flange is formed at a predetermined interval along the axial direction in the first winding portion. With such a configuration, α winding of the first winding becomes easy. In addition, preferably, a convex portion is formed on the winding partition flange separating the first main winding portion and the first sub-winding portion, which protrudes outward from the outer edge end of the winding partition flange formed within the range of the first main winding portion. The convex portion can play a role in positioning with the bobbin cover.

[0021] Preferably, the convex portion forms a notch, and the notch forms a flow gap that penetrates in the axial direction. Through the notch, a high thermal conductivity resin such as a potting resin can flow in the axial direction. As a result, the high thermal conductivity resin spreads throughout the inner coil portion formed by the first winding located inside, thereby improving heat dissipation.

[0022] Preferably, the spool cover has:

[0023] a second hollow cylindrical portion constituting the second winding portion;

[0024] a pair of cover flange portions formed at both ends of the second hollow cylindrical portion in the axial direction,

[0025] A plurality of gap retaining pieces constituting the non-winding portion are intermittently formed along the circumferential direction on the outer periphery of at least any one of the cover flange portions.

[0026] The first sub-winding portion is located inside the gap maintaining sheet.

[0027] With this configuration, it is easy to wind a plurality of turns of the first winding around the outer periphery of the first sub-winding portion.

[0028] Preferably, an opening portion is formed on the gap retaining sheet to connect the outer side and the inner side of the gap retaining sheet. With such a configuration, a high thermal conductivity resin such as a potting resin can flow inwardly along the radial direction through the opening portion. As a result, the high thermal conductivity resin spreads throughout the inner coil portion formed by the first winding located inside, thereby improving heat dissipation. The position where the opening portion is formed preferably corresponds to the position of the cutout for forming the convex portion described above. The reason for this is that the high thermal conductivity resin can easily flow inside the spool cover.

[0029] Preferably, the first winding is wound around the first main winding portion and the first sub-winding portion α. ​​By setting it as α winding, the winding of the first winding becomes easy and the axial length of the coil portion formed by the first winding can be shortened. In addition, it is easy to wind multiple turns of the first winding around the outer periphery of the first sub-winding portion.

[0030] Preferably, the coil device further comprises a housing, wherein the housing accommodates the high thermal conductivity resin so 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. By configuring in this way, the height of the coil device can be reduced and the heat dissipation can be further improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1A It is a perspective view of the coil device according to the first embodiment of the present invention.

[0032] Figure 1B It is a perspective view of a coil device according to a second embodiment of the present invention.

[0033] Figure 2A It is an exploded perspective view of the coil device shown in FIG. 1 .

[0034] Figure 2B is from Figure 2A The coil device shown is an exploded perspective view with the components mounted on the bobbin removed.

[0035] Figure 2C is from Figure 2B The coil device shown is an exploded perspective view with the components mounted on the bobbin removed.

[0036] Figure 2D Yes means Figure 2B A three-dimensional view of the lead wire portion of the outer coil and its surrounding structure shown.

[0037] Figure 2E is from Figure 2B The coil device shown is an exploded perspective view with the lead wire lead-out block mounted on the bobbin removed.

[0038] Figure 3 It is along Figure 1A A cross-sectional view of a coil device of III-III wire is shown.

[0039] Figure 4A Yes means Figure 1A A perspective view of the lead wire portion of the outer coil and its surrounding structure in the coil device shown.

[0040] Figure 4B Yes means Figure 1B A perspective view of the lead wire portion of the outer coil and its surrounding structure in the coil device shown.

[0041] Figure 5A yes Figure 4A An exploded perspective view of the insulating protection part shown.

[0042] Figure 5B yes Figure 4B An exploded perspective view of the insulating protection part shown.

[0043] Figure 6 It is a schematic perspective view for explaining how the first winding α is wound around the bobbin. DETAILED DESCRIPTION

[0044] Hereinafter, the present invention will be described based on the embodiments shown in the drawings.

[0045] First embodiment

[0046] like Figure 1AAs shown, the coil device 10 of one embodiment of the present invention has a housing 300, and the main part of the coil device 10 is accommodated inside the housing 300. In this embodiment, in the figure, the X-axis, the Y-axis, and the Z-axis are perpendicular to each other, the direction perpendicular to the installation surface of the coil device 10 is the Z-axis, and the direction in which the pair of terminals 91, 92 and the pair of terminals 91, 92 are located on opposite sides of each other is the X-axis.

[0047] like Figure 2A As shown, in the case 300, the bottom plate 340 is joined to the frame 305 having the outer side surface 310 and the inner side surface 320, and the opening edge portion 315 on the lower side of the frame 305 in the Z axis. The upper plate and the like are released in the upward direction without being joined to the opening edge portion 330 on the upper side of the frame 305 in the Z axis, and the main part of the coil device 10 can be inserted from above. At the four corners of the frame 305, concave corner portions 350 that are recessed toward the inner side of the frame 305 can be formed according to the overall shape of the coil device 10.

[0048] The frame 305 of the housing 300 is preferably made of a metal with good thermal conductivity. The metal constituting the frame 305 is not particularly limited, but examples thereof include aluminum, aluminum alloy, copper, copper alloy, stainless steel, etc. The frame 305 of the housing 300 can be manufactured by, for example, extrusion molding, stamping, or die casting.

[0049] In addition, similarly, the bottom plate 340 is also preferably made of the same metal as the frame 305, but may be a metal that is not completely the same as the frame 305. The bottom plate 340 is joined to the frame 305 by an adhesive or the like, but may also be joined to the frame 305 by bolts and nuts or the like. In addition, the bottom plate 340 and the frame 305 may be integrally formed. A cooling device such as a cooling pipe or a cooling blade may be installed below the housing 300 via a metal plate or the like, or a cooling device such as a cooling pipe or a cooling blade may be directly installed below the housing 300.

[0050] A high thermal conductivity resin is pre-stored inside the housing 300, and a main part of the coil device 10 is impregnated with the high thermal conductivity resin inside the housing 300. The high thermal conductivity resin is not particularly limited, but preferably, 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.

[0051] As resins with excellent high thermal conductivity, there are, for example, silicone resins, polyurethane resins, epoxy resins, etc., but silicone resins and polyurethane resins are preferred. In addition, in order to improve heat dissipation, fillers with high thermal conductivity may be filled in the resin. The high thermal conductivity resin of this embodiment preferably has a Shore A hardness of 100 or less, preferably 60 or less. As such a resin, a potting resin is exemplified.

[0052] like Figure 2AAs shown, the coil device 10 has four cores 12, a bobbin 40, a bobbin cover 50, and two core covers 60. The four cores 12 are assembled to form a magnetic circuit through which a magnetic flux generated by a coil described later passes. These cores 12 have a symmetrical shape and clamp the bobbin cover 50 and the bobbin 40 from the upper and lower directions (Z-axis direction in the figure) to connect them to each other.

[0053] Each core 12 is a core having a substantially E-shaped longitudinal section (including the cut surface of the Y axis and the Z axis). Each core 12 is made of a soft magnetic body such as ferrite or a metal magnetic body, and has a flat base 13 extending in the Y axis direction, a pair of side legs 16, 16 protruding in the Z axis direction from both ends of each base 13 in the Y axis direction, and a center leg 14 protruding in the Z axis direction from the middle position of each base 13 in the Y axis direction.

[0054] In this embodiment, the middle leg 14 of each core 12 enters the first through hole 44a formed in the first hollow cylinder 44 of the bobbin 40. A gap is formed between the cores 12 and 12 adjacent to each other in the X-axis direction by the separation convex portion 44b formed on the inner peripheral wall of the first hollow cylinder 44. A high thermal conductivity resin such as a potting resin is inserted into the gap, thereby improving the heat dissipation of the heat generated inside the coil device 10.

[0055] The gap formed by the separation convex portion 44b corresponds to the thickness of the separation convex portion 44b in the X-axis direction. The separation convex portion 44b is formed inside the through hole 44a, in the center of the X-axis direction, and on both sides of the Y-axis direction along the Z-axis. The thickness of the separation convex portion 44b in the X-axis direction is not particularly limited, but is preferably 0.05 to 5 mm, and more preferably 0.1 to 3 mm.

[0056] like Figure 2B As shown, the bobbin 40 has a bobbin substrate 42 in a substantially elliptical flat plate shape at its lower end in the Z-axis direction. Figure 3 As shown, the first hollow cylinder portion 44 is integrally formed so as to extend upward in the Z-axis direction.

[0057] like Figure 3 As shown, at the upper portion of the first hollow cylinder 44 in the Z-axis direction, the bobbin upper flange 48 is integrally formed in a manner protruding radially from the first hollow cylinder 44 in the Y-axis-X-axis plane. Figure 2C As shown, lead lead platforms 491 are formed integrally at both ends of the bobbin upper flange 48 in the X-axis direction. The lead lead-out portion 49 formed separately from the bobbin 40 can be joined to each lead lead-out platform 491 by fitting or bonding. Alternatively, the lead lead-out portion 49 may be formed integrally with the bobbin 40.

[0058] In this embodiment, each lead-out portion 49 is composed of a lead-out block 490 as a terminal block. Figure 2C As shown, in a lead lead block 490, the two ends of the first winding 22 constituting the inner coil 20, i.e., a pair of lead parts 22a, 22a, have a base 49c, and a pair of vertical lead grooves 490e are formed on the base 49c, which are led to the upper direction of the Z axis. Horizontal lead grooves 490f are formed on the base 490a, and the horizontal lead grooves 490f are guided to the opposite side of the Y axis direction at the upper part of the vertical lead groove 490e in the Z axis direction. Each lead part 22a, 22a is guided to each horizontal lead groove 490f. Lead connection pieces 91a, 92a of terminals 91, 92 are connected to the front end of each lead part 22a, 22a. The terminals 91, 92 are integrated by being embedded in the base 490a, but can also be integrated without being embedded in the base 490a.

[0059] In addition to replacing the lead portion 22a of a lead block 490 with the lead portion 32a, Figure 2C Another lead-out block 490 shown has the same structure. That is, Figure 2C Another lead lead block 490 shown has a base 490a, on which a pair of vertical lead grooves 490e are formed, and the pair of vertical lead grooves 490e lead the two ends of the second winding 32 constituting the outer coil 30, that is, a pair of lead parts 32a, 32a, respectively, to the upper direction of the Z axis. Horizontal lead grooves 490f are formed on the base 490a, and the horizontal lead grooves 490f are guided to the opposite side of the Y axis direction at the upper part of the vertical lead groove 490e in the Z axis direction. Each lead part 32a, 32a is guided to each horizontal lead groove 490f. Lead connection pieces 91a, 92a of terminals 91, 92 are connected to the front end of each lead part 32a, 32a. The terminal is embedded in the base 490a for integration, but it is also possible not to embed in the base 490a.

[0060] like Figure 3 As shown, a first winding portion 45 is formed on the outer periphery of the first hollow cylinder portion 44 located between the bobbin upper flange portion 48 and the bobbin base plate 42. In the first winding portion 45, as shown in FIG. Figure 6 As shown, a plurality of winding partition flanges 46 for separating winding portions adjacent to each other along the winding axis (Z axis) of the first winding 22 are formed integrally with the first hollow cylinder 44 substantially parallel to the bobbin base plate 42 (and the bobbin upper flange portion 48) at predetermined intervals along the winding axis. Details of the winding partition flanges 46 and the winding method of the first winding 22 will be described later.

[0061] The bobbin base plate 42 , the first hollow cylindrical portion 44 , the bobbin upper flange portion 48 , and the winding partition flange 46 in the bobbin 40 are preferably integrally formed by injection molding or the like.

[0062] like Figure 3 As shown, a first through hole 44a is formed inside the first hollow cylinder 44 on the bobbin substrate 42, which passes through in the Z-axis direction. The center leg 14 on the core 12 enters the first through hole 44a from the top and bottom in the Z-axis direction, and the front end of the center leg 14 approaches the first through hole 44a at the approximate center of the through hole 44a in the Z-axis direction. In addition, at the approximate center of the through hole 44a in the Z-axis direction, the front end of the center leg 14 inserted from the top and bottom of the Z-axis may form a gap at a predetermined interval without contacting.

[0063] like Figure 2C As shown, the bobbin cover 50 is composed of a pair of half bodies 50a and 50b that can be divided into two in the X-axis direction, and is combined by a split connection part 53 parallel to the winding axis (Z axis). In the combined state, the second winding part 55 is formed on the outer periphery of the cover 50. Figure 3 As shown, after the first winding wire 22 is wound around the first winding portion 45 of the bobbin 40 to form the inner coil 20, the bobbin cover 50 is mounted on the outer periphery of the bobbin 40. Figure 2C The split connection parts 53 shown are combined.

[0064] like Figure 2C As shown, the bobbin cover 50 has a second hollow cylinder 54 covering the inner coil 20 from the outside, and a cover lower flange 52 and a cover upper flange 58 are formed along the circumferential direction at a predetermined interval in the Z-axis direction on the outer periphery of the second hollow cylinder 54. The lower flange 52 and the upper flange 58 are arranged parallel to the plane of the X-Y axis and extend parallel to the installation surface.

[0065] Between the lower flange portion 52 and the upper flange portion 58 is a second winding portion 55, in which the second winding wire 32 constituting the outer coil 30, for example, which is a secondary coil, is arranged and wound (or α-wound) in the second winding portion 55. Arrangement winding refers to a common winding method of winding the winding wire from one end of the winding shaft toward the other end. α-winding will be described later.

[0066] like Figure 2B As shown, a pair of core covers 60 are mounted on the outer periphery of the bobbin cover 50 mounted with the outer coil 30 from both sides in the Y-axis direction. The core cover 60 is made of an insulating member such as synthetic resin, and has a cover body 62, whose outer peripheral surface is a guide surface for the side legs 16 on the guide core 12, and the outer coil 30 is located on its inner peripheral surface.

[0067] Mounting edges 64, 64 are integrally formed at both ends of the cover body 62 in the Z-axis direction. The mounting edge 64 on the upper side of the Z-axis engages with the upper surface of the bobbin upper flange portion 48, and the mounting edge 64 on the lower side of the Z-axis engages with the lower surface of the bobbin substrate 42, and the core cover 60 is mounted on the bobbin 40.

[0068] The cover body 62 has an inner peripheral surface shape corresponding to the outer peripheral surface shape of the core cover 60, and an insulating plate portion 66 is integrally formed at both ends in the X-axis direction. Engaging protrusions 66a protruding inward in the Y-axis direction are formed above and below the insulating plate portion 66 in the Z-axis direction. The engaging protrusions 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 engaging protrusions 66a on the lower side of the Z-axis engage with the lower surface of the bobbin substrate 42 at both ends of the bobbin substrate 42 in the X-axis direction.

[0069] The results, such as Figure 2E As shown, the insulating plate portion 66 of the core cover 60 is combined with the insulating wall 491e and the bobbin substrate 42 to improve Figure 2A The core 12 and Figure 2E The insulation of the outer coil 30 shown. The inner surface (center side of the coil device 10) of the insulating plate portion 66 may be in contact with the core 12, or may have a shape that matches the outer shape of the core 12.

[0070] like Figure 3 As shown, in this embodiment, the winding wall flange 46 of the elliptical ring shape is formed on a plane substantially parallel to the X-Y axis, so that the winding partitions 47 of the predetermined interval are formed along the Z-axis direction on the outer periphery of the first hollow cylinder 44 of the substantially elliptical cylinder shape. In this embodiment, a plurality of winding wall flanges 46 are formed substantially parallel to each other at predetermined intervals along the Z-axis direction, but the number is not particularly limited. The area where the winding wall flanges 46 are formed is the first winding portion 45.

[0071] The winding division width along the winding axis (Z axis) in each winding division 47 separated by the winding partition flange 46 is set to a width that only one winding wire 22 can enter. That is, the winding division width w1 is preferably d1<w1<(2×d1) with respect to the wire diameter d1 of the winding wire 22, and more preferably d1<w1<(1.2×d1). If the winding division width w1 is too wide with respect to the wire diameter d1, winding disorder is likely to occur, and the compactness requirement of the coil device is violated.

[0072] In addition, in each winding section 47, the winding section width is preferably the same, but may be slightly different. In addition, the winding section width between the bobbin upper flange portion 48 and the winding partition flange 46 at the uppermost position may be larger than the winding section width between the winding partition flanges 46. In addition, similarly, the winding section width between the bobbin base plate 42 and the winding partition flange 46 at the lowermost position may be larger than the winding section width between the winding partition flanges 46. In this embodiment, the predetermined total number of windings wound in each winding section 47 is not particularly limited.

[0073] like Figure 2CAs shown, in this embodiment, the partitioning protrusions 46d for inserting and positioning the lower surface of the cover lower flange portion 52 of the bobbin cover 50 are intermittently formed in a part of the circumferential direction on the winding partition flange 46 closest to the bobbin base plate 42. Figure 6 As shown, in the portion other than the partition convex piece 46d, a flow gap 46e through which the highly thermally conductive resin can flow in the axial direction is formed in a notch shape between the outer peripheral surface of the winding partition wall flange 46 and the inner peripheral surface of the bobbin cover 50.

[0074] It is preferable that the partition fin 46d also protrudes from the outer peripheral surface of the winding partition flange 46 at the position of the dividing connection portion 53 of the bobbin cover 50. The protruding height (radial height) of the partition fin 46d determines the radial width of the flow gap 46e.

[0075] At the split connection portion 53 of the bobbin cover 50 , the outer connection piece 53 b of the other half 50 b is inserted radially outward of the inner connection piece 53 a of the half 50 a , and the half parts 50 a and 50 b are connected to form the bobbin cover 50 .

[0076] The bobbin cover 50 has a second winding portion 54 that winds a second winding wire 32 different from the first winding wire 22 around the outer circumference, and a gap retaining piece 52a that is a non-winding portion disposed below the axial direction of the second winding portion 54. The gap retaining piece 52a that is the non-winding portion has an opening 52b or a cutout that connects the inside and the outside of the bobbin cover 50. The gap retaining piece 52a is formed so as to extend from the outer peripheral edge of the flange portion under the cover in the Z-axis downward direction, and its lower end can abut against the upper surface of the bobbin substrate 42.

[0077] The openings 52b are formed in the half bodies 50a and 50b located on both sides in the X-axis direction, respectively, and are formed at positions corresponding to the flow gaps 46e of the partitioning convex pieces 46d provided on the winding partition flange 46 of the bobbin 40. Figure 2E As shown, at the end in the X-axis direction, the gap retaining piece 52 a is not formed on the outer periphery of the cover lower flange portion 52 , and a highly thermally conductive resin or the like can freely enter from the gap between the cover lower flange portion 52 and the bobbin substrate 42 .

[0078] In addition, if Figure 2C As shown, the cover upper flange portion 58 of the connection portion 53a located in the half body 50a is formed with a stepped connection upper flange portion 58a which is higher than other portions along the Z axis. In addition, the cover upper flange portion 58 of the connection portion 53b located in the other half body 50b is formed with a connection upper flange portion 58b which is located below the connection upper flange portion 58a along the Z axis and can be inserted under the connection upper flange portion 58a for connection.

[0079] In addition, a stopper protrusion 58i is formed on the cover flange portion 58 of the connection portion 53b located in the other half body 50b, with which the connection front end of the connection upper flange portion 58a can abut. The stopper protrusion 58i protrudes upward along the Z axis relative to the upper surface of most of the cover flange portion 58. The protrusion height of the stopper protrusion 58i relative to the upper surface of most of the cover flange portion 58 is preferably substantially the same as the protrusion height of the connection upper flange portion 58a along the Z axis. The upper surface of these stopper protrusions 58i and the upper surface of the connection upper flange portion 58a are in contact with the lower surface of the bobbin upper flange portion 48 of the bobbin 40, and an air outlet gap is formed between the upper surface of most of the cover flange portion 58 except the split connection portion 53 and the lower surface of the bobbin upper flange portion 48.

[0080] The cover upper flange portion 58 on the opposite side of the connecting upper flange portion 58a along the X-axis of the half body 50a is provided with an engaging protrusion 58c protruding upward from the upper surface of the cover upper flange portion 58 along the Z-axis. An engaging surface 58e is formed on the upper surface of the engaging protrusion 58c, and the protruding height of the engaging surface 58e relative to the upper surface of the cover upper flange portion 58 along the Z-axis is the same as the step height of the connecting flange portion 58a. The engaging surface 58e contacts the lower surface of the lead wire lead-out platform 491. The lower surface of the lead wire lead-out platform 491 is at a height substantially the same as the lower surface of the bobbin upper flange portion 48 along the Z-axis. A step protrusion 58g may also be formed on the upper surface of the cover upper flange portion 58 located between the engaging portion 58c and the connecting upper flange portion 58a. The step height of the step protrusion 58g is the same as the step height of the connecting flange portion 58a.

[0081] The cover upper flange portion 58 on the opposite side of the connecting upper flange portion 58b along the X-axis of the other half body 50b is provided with an engaging protrusion 58d protruding upward from the upper surface of the cover upper flange portion 58 along the Z-axis. An engaging surface 58f is formed on the upper surface of the engaging protrusion 58d, and the protruding height of the engaging surface 58f relative to the upper surface of the cover upper flange portion 58 along the Z-axis is the same as the protruding height of the stop protrusion 58i. The engaging surface 58f is in contact with the lower surface of the lead wire lead-out platform 491. The lower surface of the lead wire lead-out platform 491 is at a height substantially the same as the lower surface of the bobbin upper flange portion 48 along the Z-axis. A step protrusion 58h may also be formed on the upper surface of the cover upper flange portion 58 between the engaging portion 58d and the stop protrusion 58i. The step height of the step protrusion 58h is the same as the step height of the stop protrusion 58i.

[0082] Figure 2C The first winding 22 shown can be made of a single wire or a twisted wire, preferably an insulated coated wire. The outer diameter d1 of the first winding 22 is not particularly limited, but when a large current flows, it is preferably The second winding 32 may be the same as or different from the first winding 22 .

[0083] In this embodiment, the inner coil 20 formed by the first winding 22 constitutes the primary coil of the transformer, and the outer coil 30 formed by the second winding 32 wound around the bobbin cover 50 constitutes the secondary coil. Figure 3 As shown, the wire diameter of the second winding 32 constituting the outer coil 30 is larger than the wire diameter of the first winding 22, but the wire diameter is not particularly limited and the wire diameters can be the same or different. In addition, the materials of the first winding 22 and the second winding 32 can be the same or different.

[0084] like Figure 6 As shown, in the bobbin 40 of the present embodiment, at least one connecting groove 46a is formed on each winding partition flange 46 to connect adjacent winding sections 47. In the present embodiment, the circumferential position of at least one of the pair of cutout edges 46b, 46c formed on the winding partition flange 46 in a manner to define the circumferential width of each connecting groove 46a is different between the adjacent winding partition flanges 46 along the Z-axis direction (winding axis), but may be the same position. In addition, the circumferential direction refers to the direction along the elliptical outer peripheral surface of the hollow cylinder 44.

[0085] In this embodiment, if Figure 6 As shown, one of the pair of notch edges 46b and 46c is inclined toward the lower right direction, and the other notch edge 46b is inclined toward the lower right direction except for the next-wall flange 46 formed with the partition convex piece 46d. Only in the next-wall flange 46 formed with the partition convex piece 46d, the notch edge 46b is inclined in the opposite direction, so that the circumferential width of the connection groove 46a is wider than that of other parts.

[0086] In the bobbin 40 of the present embodiment, the first winding 22 is α-wound, for example, from the center of the first winding portion 45 in the Z-axis direction. That is, the center portion 22b of the first winding 22 is arranged to pass through the connection groove 46a located in the center of the first winding portion 45 in the Z-axis direction, and the lower winding portion 22c is passed from the center to one end through the next-stage winding division 47. In addition, the other upper winding portion 22d is passed from the center of the first winding 22 to one end through the winding division 47 located in the upper stage of the winding division 47 through which the lower winding portion 22c passes.

[0087] Then, when viewed from the Z axis, the lower winding portion 22c is wound rightwardly at the same winding section 47 more than once, and when viewed from the Z axis, the upper winding portion 22d is wound leftwardly at the same winding section 47 at the previous level more than once. Then, the lower winding portion 22c moves from the winding section 47 to the next winding section 47 in the Z axis direction through the connecting groove 46a, and is wound in the same direction in the winding section 47. In addition, the upper winding portion 22d moves from the winding section 47 to the previous winding section 47 through the connecting groove 46a, and is wound in the same direction in the winding section 47.

[0088] By repeating this operation, the first winding wire α is wound around the first winding portion 45. In the present embodiment, the first winding portion 45 is divided into a first main winding portion 45a located between the partitioning protrusion 46d and the bobbin upper flange portion 48, and a first sub-winding portion 45b located between the partitioning protrusion 46d and the bobbin base plate 42. Figure 3 As shown, in the first main winding portion 45a, the first winding 22 is wound along the radial direction α by one or more layers, and in the first sub-winding portion 45b, the first winding 22α is wound by a number of layers (the number of first sub-winding layers) that is greater than the number of radial winding layers (the number of first main winding layers) wound in the first main winding portion 45a.

[0089] Moreover, the position of the outermost peripheral layer of the first winding 22 wound on the first sub-winding portion 45b is located outside the cylinder wall of the second winding portion 55. With this configuration, when viewed from the axial direction, the flange-shaped coil portion 20a of the first winding 22 wound on the first sub-winding portion 45b and the outer coil portion 30 of the second winding 32 wound on the second winding portion 55 overlap.

[0090] Will Figure 3 The lead wire portion 22a from the flange-shaped coil portion 20a is located at the lower end of the lower winding portion of the first winding 22 after α winding. Figure 2D The gap between the bobbin substrate 42 and the cover lower flange 52 is led out along the X-axis direction to the outside of the bobbin cover 50. The lead wire portion 22a led out to the outside of the bobbin cover 50 stands upward along the lead wire passage 240 of the insulating plate 200 in the Z-axis direction.

[0091] The lead wire passage 240 is formed between a pair of plate outer side protruding pieces 230 formed on the plate body 210. A plate top plate 220 is formed on the upper portion of the plate body 210 in the Z-axis direction. The plate top plate 220 is inserted between the lead wire lead-out platform 491 of the bobbin 20 and the engaging portion 58d of the bobbin cover 50 and fixed.

[0092] The lead portion 22a that rises upward in the Z-axis direction along the lead passage 240 of the insulating plate 200 passes through the base lead groove 491a formed in the lead lead platform 491 and is led out to the upper side of the lead lead portion 49. The lead portion 22a that is led out to the upper side of the lead lead platform 491 passes through the base lead groove 491a formed in the lead lead platform 491. Figure 2C The lead lead-out portion 22a passing through the vertical lead-out groove 490e is led outward along the horizontal lead-out groove 490f of the block 490 in the Y-axis direction and connected to the lead connection piece 92a of the terminal 92.

[0093] In addition, if Figure 2D As shown, from Figure 2C The lead wire portion 22a of the upper winding portion of the first winding wire 22 after the α winding shown passes through another base lead-out groove 491c of the lead connection platform 491. The lead wire portion 22a passing through the base lead-out groove 491c passes through Figure 2C The vertical lead-out groove 490e of the base block 490 is shown. The lead lead-out portion 22a passing through the vertical lead-out groove 490e is led out to the outside in the Y-axis direction along the horizontal lead-out groove 490f of the block 490, and connected to the lead connection piece 91a of the terminal 91. In addition, in this embodiment, "outside" refers to the side of the bobbin 40 away from the central axis, and "inside" refers to the side of the bobbin close to the central axis.

[0094] In contrast, Figure 3 As shown, in the bobbin cover 50, the second winding 32 constituting the outer coil 30 serving as the secondary coil is wound in a row on the second winding portion 55. The row winding refers to a winding method of winding the winding 32 sequentially from one end toward the other end in the Z-axis direction on the outer peripheral surface of the winding portion 55. In this embodiment, the winding is carried out in a row in the radial direction in one layer or two or more layers. Assuming that two layers are wound in a row or in a row, the first layer is wound first, and then the second layer is wound thereon.

[0095] Will constitute Figure 2C Each lead wire portion 32a of the second winding wire 30 of the outer coil 30 shown in the figure passes through the through groove and the engagement portion 58c formed in the bobbin cover 50. Figure 2E The lead wire lead-out groove 491c of the base of the lead wire lead-out platform 491 is shown, and the lead wire portions 32a, 32a led out to the upper side of the lead wire lead-out platform 491 pass through Figure 2E The vertical lead-out grooves 490e of the base block 490 are shown. The lead lead-out portions 22a, 22a passing through the vertical lead-out grooves 490e are led out to the outsides on the opposite sides of each other in the Y-axis direction along the horizontal lead-out grooves 490f, 490f of the block 490, and are connected to the lead connection pieces 91a, 92a of the terminals 91, 92, respectively.

[0096] like Figure 2EAs shown, the lead lead portion 49 is composed of a lead lead block (terminal block) 490 and a lead lead stage 491, and the lead lead block 490 is provided with terminals 91 and 92. In the present embodiment, the terminals 91 and 92 are fixed (integrated) by embedding the lead lead block 490 by insert molding, etc., but can also be installed separately.

[0097] like Figure 4A and Figure 5A As shown, the terminals 91 and 92 have lead connection pieces 91a and 92a. Figure 2C The lead wire portions 22a, 22a of the inner coil 20 (first winding 22) or the lead wire portions 32a, 32a of the outer coil 30 (second winding 32) are shown. Figure 4A and Figure 5A As shown, the lead connection pieces 91a, 92a have a substantially C-shape, and sandwich the lead portions 22a, 22a or the lead portions 32a, 32a led outward in the Y-axis direction.

[0098] like Figure 4A and Figure 5A As shown, the side extension pieces 91b and 92b are integrally connected to the ends of the lead connection pieces 91a and 92a in the X-axis direction. When viewed from the lead connection pieces 91a and 92a, the side extension pieces 91b and 92b extend toward the outside of the Y-axis direction (in the direction away from the wire axis 40), and the extension direction thereof is substantially consistent with the extension direction of the lead portions 22a and 22a or the lead portions 32a and 32a.

[0099] like Figure 4A and Figure 5A As shown in FIG. 1 , upper extension pieces 91c and 92c are integrally connected to the ends of the inner sides of the side extension pieces 91b and 92b in the Y-axis direction (the opposite side to the side where the lead connection pieces 91a and 92a are arranged). The upper extension pieces 91c and 92c extend upward in the Z-axis direction and extend to the upper side of the upper opening edge 330 of the housing 300. That is, a part of the upper extension pieces 91c and 92c extends upward from the upper opening edge 330.

[0100] The upper ends of the upper extension pieces 91c and 92c in the Z-axis direction are integrally connected with the housing cross-sections 91d and 92d. The housing cross-sections 91d and 92d extend from the center of the bobbin 40 toward the outside along the X-axis direction. A step corresponding to the height of the upper extension pieces 91c and 92c is formed between the housing cross-sections 91d and 92d and the side extension pieces 91b and 92b. Figure 3As shown, the housing cross-sections 91d and 92d extend across the inside and outside of the housing 300 along the X-axis direction, and cross (cross or span) the upper opening edge 330 of the housing 300, and extend from the inside of the housing 300 toward the outside above the upper opening edge 330. The housing cross-sections 91d and 92d have a flat plate shape parallel to the X-Y plane, but may also have a curved structure such as a curved surface.

[0101] like Figure 4A and Figure 5A As shown, the outer ends of the shell cross-sections 91d and 92d in the X-axis direction are integrally connected with lower extension pieces 91e and 92e. The lower extension pieces 91e and 92e have a flat plate shape parallel to the Y-Z plane and extend downward in the Z-axis direction. The lower extension pieces 91e and 92e have a shape that is longer than the upper extension pieces 91c and 92c in the Z-axis direction, as shown in FIG. Figure 3 As shown, the outer side of the housing 300 extends downward from the housing cross-sections 91d and 92d.

[0102] The downward extending pieces 91 e and 92 e extend along the outer side surface 310 of the housing 300 , and extend downward from above the upper opening edge 330 of the housing 300 along the Z-axis direction.

[0103] like Figure 4A and Figure 5A As shown, the outer protruding pieces 91f and 92f are integrally connected to the lower ends of the lower extension pieces 91e and 92e in the Z-axis direction, that is, the inner sides in the Y-axis direction. The outer protruding pieces 91f and 92f have a flat plate shape parallel to the X-Z plane and extend in the X-axis direction. Figure 3 As shown, the outward protruding pieces 91f and 92f extend in a direction away from the outer side surface 310 of the housing 300.

[0104] The distance from the upper opening edge 330 of the housing 300 to the outer protruding pieces 91f, 92f in the Z-axis direction is determined by the length of the lower extending pieces 91e, 92e in the Z-axis direction, but the distance is not limited to the example shown in the figure and can also be set to be longer. In addition, in the present embodiment, the outer protruding pieces 91f, 92f have a flat plate shape parallel to the X-Z plane, but can also be a flat plate shape parallel to the X-Y plane or a flat plate shape that is a plane between the X-Z plane and the X-Y plane.

[0105] like Figure 2EAs shown, the lead wire lead-out platform 491 is formed integrally with the bobbin 40 and is arranged at each end of the bobbin upper flange portion 48 of the bobbin 40 in the X-axis direction. An insulating wall 491e is formed between the lead wire lead-out platform 491 and the bobbin upper flange portion 48. The insulating wall 491e has a flat plate shape parallel to the Y-Z plane and abuts against the insulating plate portion 66 of the core cover 60. The position of the upper end of the insulating wall 491e is roughly the same as the position of the upper end of the insulating plate portion 66. The insulating wall 491e is to Figure 2A When the core 12 shown is mounted on the bobbin 40 , the core 12 and the lead wire portion 32 a (or 22 a ) of the outer coil 30 (or the inner coil 20 ) are insulated from each other.

[0106] The insulating wall 491e is formed with a fixing recess 491f that is recessed toward the center of the bobbin 40. The fixing recess 491f is disposed between a pair of insulating plate portions 66 of the core cover 60 and is disposed so as to be substantially flush with the insulating plate portions 66 inside the insulating plate portions 66.

[0107] A base center portion 491a and two base side portions 491b, 491b are formed at each end of the bobbin upper flange portion 48 in the X-axis direction. The base center portion 491a and the base side portion 491b have a shape that extends the bobbin upper flange portion 48 outward in the X-axis direction, and have a substantially flat plate shape parallel to the X-Y plane. The base center portion 491a is disposed between the two base side portions 491b, 491b.

[0108] A base lead-out groove 491c is formed between one base side portion 491b and the base center portion 491a. Similarly, a base lead-out groove 491c is formed between the other base side portion 491b and the base center portion 491a. The lead portion 32a (or 22a) of the outer coil 30 (or the inner coil 20) can be inserted through the base lead-out groove 491c. The base lead-out groove 491c extends along the X-axis direction.

[0109] A side thin plate portion 491d is formed at the outer end of the base side portion 491b in the Y-axis direction. 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. The groove 490i of the lead lead block 490 described later is engaged with the side thin plate portion 491d.

[0110] The lead block 490 has a function as a terminal block for fixing the terminals 91 and 92, and is formed separately from the bobbin 40 (lead block 491). As a material constituting the lead block 490, for example, a resin different from the bobbin 40 can be selected, for example, a resin with better formability than the bobbin 40 or a resin with good heat dissipation can be selected. Specifically, resin materials such as PET, PBK, or PPS can be cited.

[0111] like Figure 5A As shown, the lead block 490 has a base 490a, and an engaging protrusion 490g is formed substantially in the center of the base 490a in the Y-axis direction. The engaging protrusion 490g protrudes from the inner end of the base 490a in the X-axis direction toward the center of the bobbin.

[0112] Two front wall portions 490b and 490b are formed on the inner end surface of the base 490a in the X-axis direction so as to sandwich the engaging protrusion 490g therebetween. One front wall portion 490b is arranged on one side of the base 490a in the Y-axis direction, and the other front wall portion 490b is arranged on the other side of the base 490a in the Y-axis direction. The front wall portion 490b has a wall surface parallel to the Y-Z plane, such as Figure 2E As shown, the front surface of the front wall portion 490b abuts against the insulating wall 491e.

[0113] 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 side of the inner end surface of the front wall portion 490b where the engaging convex portion 490g is disposed. The inner end surface of each fixing convex portion 490h formed on each front wall portion 490b abuts against each end in the Y-axis direction of the fixing concave portion 491f formed on the insulating wall 491e of the lead lead platform 491. Thus, when the lead lead block 490 is mounted on the lead lead platform 491, the lead lead block 490 can be prevented from being misaligned in the Y-axis direction relative to the lead lead platform 491.

[0114] A vertical lead-out groove 490e is formed between the engaging protrusion 490g and a front wall portion 490b. Similarly, a vertical lead-out groove 490e is formed between the engaging protrusion 490g and another front wall portion 490b. The vertical lead-out 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 lead-out groove 490e. The lead portion 32a (or 22a) is led out toward the upper part of the Z-axis direction inside the vertical lead-out groove 490e. That is, the vertical lead-out groove 490e plays the role of a guide groove that aligns with the base lead-out groove 491c of the lead lead-out platform 491 and guides the lead portion 32a to the upper part of the Z-axis direction.

[0115] A rear wall portion 490c extending from one side in the Y-axis direction to the other side is formed at the rear end in the X-axis direction of the base 490a (outside the bobbin). Figure 5A As shown, two terminal holes 490j are formed in the rear wall portion 490c at a predetermined interval in the Y-axis direction. The housing cross-sections 91d and 92d of the terminals 91 and 92 are led out through the terminal holes 490j.

[0116] A horizontal lead-out groove 490f is formed between the rear wall portion 490c and the front wall portion 490b. The horizontal lead-out groove 490f extends toward the outside 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 lead-out groove 490f. In more detail, the lead portion 32a led out toward the upper side in the Z-axis direction along the vertical lead-out groove 490e is bent toward the Y-axis direction, and is led out toward the outside in the Y-axis direction along the horizontal lead-out groove 490f. That is, the horizontal lead-out groove 490f plays the role of a guide groove that guides the lead portion 32a (or 22a) toward the outside in the Y-axis direction.

[0117] 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 from the base 490a in the Z-axis direction. The terminal hole 490j is connected to the side wall portion 490d, and the side extension pieces 91b and 92b of the terminals 91 and 92 are led out through the terminal hole 490j.

[0118] A groove 490i is formed in the side wall portion 490d. The groove 490i is formed on the inner side of the side wall portion 490d in the Y-axis direction and extends along the X-axis direction. Figure 2E ) while inserting it into the groove 490i, and engaging the groove 490i with the side thin plate portion 491d. In this way, the lead lead platform 491 can be engaged with the lead lead block 490, and the lead lead block 490 can be fixed to the lead lead platform 491. In addition, the side wall portion 490d can also be filled with a ratio of Figure 3 The resin upper surface LS of the high thermal conductivity resin inside the housing 300 shown in the figure is formed so as to extend downward. In this case, the block 490 is in contact with the high thermal conductivity resin filled inside the housing 300 to dissipate heat.

[0119] like Figure 4A and Figure 5A As shown, the insulating protection part 100 has an inner extension part 110, a shell cross-section part 120, and an outer extension part 130. The insulating protection part 100 is between the terminals 91, 92 and the shell 300 to insulate the terminals 91, 92 from the shell 300 (refer to Figure 3 In the present embodiment, the insulating protection portion 100 and the lead-out block 490 are formed separately and are held or fixed to the housing 300 in a removable manner.

[0120] The insulating protection part 100 is made of an insulating material. As the material constituting the insulating protection part 100, polyimide resin, silicone resin, epoxy resin, acrylic resin, polyetheretherketone resin, polyethersulfone resin, polyacetal resin or aromatic polyamide resin can be used. In addition, resins or other components having heat resistance (or elasticity) in addition to insulation can also be used.

[0121] The insulating protection part 100 has a thin plate (flat plate) shape and is formed in a substantially C-shape. Figure 3 As shown, the insulating protection part 100 is installed on the housing 300 in a manner spanning the outer side surface 310, the inner side surface 320, and the upper opening edge 330 of the housing 300. The thickness of the insulating protection part 100 is preferably 0.5 to 1.0 mm. However, the thickness of the insulating protection part 100 is not limited to the above thickness, and can be appropriately determined within a range that can effectively ensure the insulation between the terminals 91 and 92 arranged on its surface and the housing 300 arranged on its back. The width of the insulating protection part 100 in the Y-axis direction is larger than the interval between the terminals 91 and 92 in the Y-axis direction.

[0122] like Figure 3 and Figure 5A As shown, the inner extension portion 110 has a flat plate shape parallel to the YZ plane and extends along the inner side surface 320 of the housing 300. The inner extension portion 110 abuts against the inner side surface 320 of the housing 300. The length of the inner extension portion 110 in the Z-axis direction is appropriately determined within a range that enables the insulating protection portion 100 to be reliably held (hooked) on the upper opening edge 330 of the housing 300. Figure 3 As shown, the inner extension portion 110 is preferably formed so as to extend downward from the resin upper surface LS of the high thermal conductive resin accommodated in the housing 300 .

[0123] The housing cross-cutting portion 120 is integrally connected to the upper end of the inner extension portion 110 in the Z-axis direction. The housing cross-cutting portion 120 extends in the X-axis direction in a direction away from the bobbin 40 (outside the bobbin 40). The housing cross-cutting portion 120 extends in the X-axis direction in a manner spanning the inside and outside of the housing 300, and spans (crosses or crosses) the upper opening edge 330 of the housing 300, and at the same time extends from the inside of the housing 300 to the outside on the upper surface of the upper opening edge 330.

[0124] The housing cross-section 120 has a flat plate shape parallel to the X-Y plane and abuts against the upper opening edge 330 of the housing 300. The housing cross-section 120 and the housing cross-sections 91d and 92d of the terminals 91 and 92 are opposite. The length of the housing cross-section 120 in the X-axis direction is substantially equal to the length of the upper opening edge 330 of the housing 300 in the X-axis direction. Figure 3In the example shown, a predetermined gap is formed between the housing cross-cut portion 120 and the housing cross-cut pieces 91 d and 92 d of the terminals 91 and 92 , but they may be in contact with each other.

[0125] The outer extension portion 130 is integrally connected to the outer end of the housing cross-section portion 120 in the X-axis direction. The outer extension portion 130 has a flat plate shape parallel to the Y-Z plane and extends downward in the Z-axis direction. The outer extension portion 130 abuts against the outer side surface 310 of the housing 300. The outer extension portion 130 has a shape longer than the inner extension portion 110 in the Z-axis direction and extends downward from the housing cross-section portion 120 along the outer side surface 310 of the housing 300.

[0126] The outer extension portion 130 is opposed to the lower extension pieces 91e and 92e of the terminals 91 and 92. Figure 3 In the illustrated example, a predetermined gap is formed between the outer extending portion 130 and the lower extending pieces 91 e and 92 e , but they may be in contact with each other.

[0127] The lower end of the outer extension portion 130 in the Z-axis direction is arranged at a position lower in the Z-axis direction than the lower ends of the lower extension pieces 91e and 92e of the terminals 91 and 92. Thus, the insulation between the lower extension pieces 91e and 92e and the outer side surface 310 of the housing 300 can be reliably achieved via the outer extension portion 130.

[0128] In this embodiment, the terminals 91 and 92 are covered by the shell cross-cut portion 120 and the outer extension portion 130 of the insulating protection portion 100 on the upper portion of the shell 300 exposed from the lead lead portion 49 (lead lead block 490), thereby forming an insulating area in this portion.

[0129] The coil device 10 of this embodiment is assembled Figure 2A to Figure 2E The coil device 10 of the present embodiment is manufactured by installing the components shown in the figure and winding the winding wires 22 and 32 around the bobbin 40 and the bobbin cover 50. The coil device 10 of the present embodiment is accommodated in the housing 300, but the housing 300 is not an essential component.

[0130] Next, an example of a method for manufacturing the coil device 10 is described. In manufacturing the coil device 10, first, a Figure 2C The bobbin 40 shown in FIG. The material of the bobbin 40 is not particularly limited, but the bobbin 40 is formed of an insulating material such as resin.

[0131] Next, the first winding 22 is wound around the outer periphery of the first hollow cylinder 44 of the bobbin 40 to form the inner coil 20. The first winding 22 used to form the inner coil 20 is not particularly limited, but preferably a stranded wire or the like is used. In the inner coil 20, a flange-shaped coil portion 20a having an outer diameter larger than that of other inner coil 20 portions is formed at the Z-axis lower end of the inner coil portion 20 by α winding.

[0132] Next, the bobbin cover 50 is mounted on the bobbin 40 formed with the inner coil 20. The second winding 32 constituting the outer coil 30 is wound around the outer periphery of the second hollow cylinder 54 on the bobbin cover 50. The flange-shaped coil portion 20a is located inside the gap retaining piece 52a of the cover lower flange portion 52 on the bobbin cover 50. That is, Figure 3 The illustrated first sub-winding portion 45 b is located on the inner side of the gap maintaining piece 52 a of the cover lower flange portion 52 .

[0133] The lead portions 22 a and 32 a are passed through the base lead-out grooves 491 c of the lead connection base 491 , and then the lead lead-out blocks 490 and 490 are slidably moved from the outside in the X-axis direction and mounted on the bases 491 .

[0134] Afterwards, Figure 2C The core cover 60 shown is mounted on both sides of the Y-axis direction on the bobbin cover 50, and then the core 12 is mounted from the upper and lower directions of the Z-axis direction. That is, the front ends of the middle legs 14, 14 of the core 12 and the front ends of the side legs 16, 16 are brought close to each other. In addition, a gap may be provided between the front ends of the middle legs 14, 14.

[0135] As the material of each core 12, soft magnetic materials such as metal and ferrite can be cited, but it is not particularly limited. The core 12 can be fixed to the bobbin cover 50 and the bobbin 40 by bonding with an adhesive or winding with a belt-shaped member on the periphery, or it can be only installed on the bobbin cover 50 and the bobbin 40. In this embodiment, as shown in Figure 1, most of the coil device 10 assembled in this way is accommodated in the interior of the housing 300.

[0136] like Figure 3 As shown, inside the housing 300, a high thermal conductivity resin such as a potting resin is filled to the position of the resin upper surface LS in a state where the coil device 10 is housed. The position of the resin upper surface LS is preferably located below the opening edge 330 on the upper side of the housing 300 in the Z-axis direction and close to the lower surface position of the bobbin upper flange portion 48 of the bobbin 40. The gap in the Z-axis direction between the resin upper surface LS and the opening edge 330 on the upper side of the housing 300 is preferably 3 mm to 10 mm.

[0137] The core 12 may be provided with the heat sink 80 in contact with the upper surface and the side surface in the Y-axis direction of the core 12, and the side legs extending downward from both ends in the Y-axis direction of each heat sink 80 are immersed in the high-conductivity resin stored in the housing 300. With this configuration, the heat of the upper portion of the core 12 is transferred to the high-conductivity resin stored in the housing 300, and heat dissipation can be efficiently achieved. The heat sink 80 is preferably made of a high-conductivity material such as a metal such as aluminum.

[0138] Furthermore, the high thermal conductive resin is preferably filled into the case 300 before the coil device 10 is accommodated in the case. However, the resin filling may be performed after the coil device 10 is accommodated in the case.

[0139] The coil device 10 of the present embodiment can be used as a vertical coil device in which the winding axis of the coil is arranged perpendicularly to the mounting substrate surface. Therefore, the core 12 inserted into the hollow portion of the bobbin 40 can be easily cooled.

[0140] Furthermore, in this embodiment, if Figure 2C As shown, the bobbin cover 50 can be divided by the dividing connection portion 53 parallel to the winding axis, so the bobbin cover 50 can be easily arranged on the outer periphery of the bobbin 40.

[0141] like Figure 3 As shown, in the coil device 10 of the present embodiment, since the winding 22 is wound in such a manner that each winding section 47 has only a single winding portion along the winding axis direction, it is easy to prevent the number of windings of the winding 22 per layer in the radial direction from varying, and this contributes to the stabilization of the leakage characteristics (coil coupling). That is, it is easy to strictly control the coupling coefficient between the outer coil 30 constituting the secondary coil and the inner coil 20 constituting the primary coil, and the coil device 10 of the present embodiment can be suitably used as a leakage transformer.

[0142] In addition, in this embodiment, if Figure 2C As shown in FIG. 1 , the outer edge end of the cover lower flange portion 52 of the bobbin cover 50 is provided with gap retaining pieces 52a intermittently. Figure 3 As shown, at the lower end portion of the first coil 20 in the Z-axis direction, a flange-shaped coil portion 20 a having a large number of radially wound layers is easily formed.

[0143] Furthermore, in this embodiment, if Figure 2D As shown, the insulating plate 200 is mounted on one end of the bobbin cover 50 in the X-axis direction. Therefore, it is easy to take out the lower lead portion 22a of the first winding 22 constituting the inner coil 20 from under the cover lower flange portion 52 of the cover 50, while ensuring insulation from the outer coil 30 and guiding the lead wire taking-out stage 491.

[0144] In addition, in this embodiment, if Figure 3 As shown, a flow gap is uniformly formed between the outer peripheral edge of the winding partition flange 46 and the inner peripheral surface of the bobbin cover 50. With this structure, the distance between the coils 20 and 30 wound on the inner and outer sides of the bobbin cover 50 is easily constant, and the variation of the coil characteristic value is reduced.

[0145] In particular, in the coil device 10 of the present embodiment, Figure 2C As shown, the bobbin cover 50 has a gap retaining piece 52a, and the gap retaining piece 52a has an opening 52b or a cutout. Therefore, a high thermal conductivity resin such as a potting resin enters the inside of the bobbin cover 50 through the opening 52b or the cutout, and enters between the bobbin cover 50 and the bobbin 40. As a result, the first winding 22 of the first winding portion 45 wound on the bobbin 40 contacts the high thermal conductivity resin, and the heat from the first winding 22 is transferred to the high thermal conductivity resin to dissipate heat well. Therefore, in the coil device 10 of this embodiment, even if the coil device 10 is miniaturized, the heat dissipation is excellent.

[0146] In addition, in this embodiment, if Figure 2C As shown, the bobbin cover 50 has a cover lower flange portion 52 and a cover upper flange portion 58. In addition, a gap retaining piece 52a is provided below the cover lower flange portion 52. In addition, the cover upper flange portion 58 is arranged on the axial lower side of the bobbin upper flange portion 48, and an outlet gap is formed between the bobbin upper flange portion 48 and the cover upper flange portion 58, which can discharge the air inside the bobbin cover 50 to the outside. The outlet gap is formed by the connection upper flange portion 58a, the step convex portions 58g, 58h and the stop convex portion 58i formed on the upper surface of the cover upper flange portion 58 abutting against the lower surface of the bobbin upper flange portion 48.

[0147] With this configuration, when the highly thermally conductive resin enters the inside of the bobbin cover 50 from below the cover lower flange portion 52, the air inside the bobbin cover 50 is easily discharged from the outlet gap, and the flow of the resin becomes smoother.

[0148] Furthermore, in the present embodiment, the first winding 22 disposed on the inner circumference is the primary coil of the transformer, but conversely, it may be the secondary coil (inner coil 20) to which a high voltage is further applied. In this case, the secondary coil (inner coil 20) to which a high voltage is applied is disposed inside the primary coil (outer coil 30) to which a relatively low voltage is applied, thereby making it easy to insulate.

[0149] Moreover, in the coil device 10 of the present embodiment, the terminals 91 and 92 have housing cross-sections 91d and 92d and lower extension pieces 91e and 92e. Therefore, the terminals 91 and 92 extend to the side of the housing 300 (along the extension direction of the housing cross-sections 91d and 92d) instead of extending to the top of the housing 300, and it is not necessary to set the terminal block (lead lead block 490) for fixing the terminals 91 and 92 above the housing 300. Therefore, most of the coils 20, 30 and the core 12 can be accommodated inside the housing 300, and by filling the housing 300 with heat dissipation resin (high thermal conductivity resin), most of the coils 20, 30 and the core 12 are immersed in the heat dissipation resin, and the heat of the coils 20, 30 and the core 12 can be fully dissipated through the heat dissipation resin.

[0150] In addition, in the coil device 10 of the present embodiment, as described above, since the terminal block (lead lead block 490) does not need to be provided above the housing 300, the height of the coil device 10 can be suppressed, and the height of the coil device 10 can be reduced.

[0151] In addition, in the coil device 10 of the present embodiment, since the terminals 91 and 92 are provided with the downward extension pieces 91e and 92e, it is not necessary to lead the terminals 91 and 92 to the lower outside of the housing 300 by providing, for example, a cutout or the like at the lower part of the housing 300. Therefore, when the heat dissipation resin is filled in the housing 300, the heat dissipation resin does not leak out from the cutout or the like, and a sufficient amount of the heat dissipation resin is filled in the housing 300, so that the heat of the coils 20 and 30 and the core 12 can be efficiently dissipated through the heat dissipation resin.

[0152] In addition, in this embodiment, the terminals 91 and 92 have the outward protruding pieces 91f and 92f. Therefore, the outward protruding pieces 91f and 92f can be used as user terminals.

[0153] In addition, the coil device 10 of the present embodiment includes the insulating protection portion 100 . Therefore, the terminals 91 and 92 can be led out to the side of the housing 300 while preventing a short circuit failure between the terminals 91 and 92 and the housing 300 via the insulating protection portion 100 .

[0154] In addition, in this embodiment, the insulating protection portion 100 has the housing cross-cut portion 120 and the outer extension portion 130. Therefore, the terminals 91 and 92 can be insulated from the upper opening edge 330 of the housing 300 via the housing cross-cut portion 120, and the terminals 91 and 92 can be insulated from the outer side surface 310 of the housing 300 via the outer extension portion 130.

[0155] In addition, in this embodiment, the lead block 490 is provided, and the insulating protection part 100 is formed separately from the lead block 490. Therefore, the structure of the lead block 490 or the insulating protection part 100 can be simplified, and the lead block 490 or the insulating protection part 100 can be easily formed.

[0156] In addition, in the present embodiment, the lead-out block 490 is formed separately from the bobbin 40. Therefore, when the specification of the lead-out block 490 is changed, it is sufficient to prepare the lead-out block 490 corresponding to the specification and install it on the bobbin 40. That is, it is not necessary to change the overall design of the bobbin, and it is possible to flexibly respond to the specification change.

[0157] Moreover, if Figure 3 As shown, in the coil device 10 of the present embodiment, the inter-coil coupling can be adjusted by the radial gap between the inner coil portion 20 of the first winding 22 wound on the first main winding portion 45a and the outer coil portion 30 of the second winding 32 wound on the second winding portion 55. Moreover, in the coil device 10 of the present embodiment, the inter-coil coupling can also be adjusted by the Z-axis gap between the flange-shaped coil portion 20a of the first winding 22 wound on the first sub-winding portion 45b and the outer coil portion of the second winding 32 wound on the second winding portion 55.

[0158] In addition, if the number of winding layers of the first winding 22 wound on the first sub-winding portion 45b is increased, the overlapping area of ​​the flange-shaped coil portion 20a and the outer coil portion 30 observed from the axial direction is also increased, and the leakage characteristics can be adjusted. In this way, in the coil device 10 of this embodiment, the leakage characteristics can be adjusted by both the radial gap and the axial gap.

[0159] In addition, in the coil device 10 of the present embodiment, by increasing the number of winding layers of the first winding 22 wound on the first sub-winding portion 45b of the first winding portion 45, the total number of turns of the first winding 22 can be increased, and thus the axial dimension of the bobbin 40 can be shortened. Therefore, the height of the coil device 10 can be reduced.

[0160] Moreover, in the present embodiment, the outermost peripheral layer of the flange-shaped coil portion 20a wound on the first sub-winding portion 45b is located outside the cylinder wall of the second winding portion 55. By configuring in this way, the flange-shaped coil portion 20a and the outer coil portion 30 overlap when viewed from the axial direction. Therefore, the axial gap between the flange-shaped coil portion 20a of the first winding 22 wound on the first sub-winding portion 45b and the outer coil portion 30 of the second winding 32 wound on the second winding portion 55 makes it easy to adjust the leakage characteristics.

[0161] In addition, in the present embodiment, the winding partition flange 46 is formed at a predetermined interval along the Z-axis direction in the first winding portion 45. With such a configuration, the α winding of the first winding 22 becomes easy. In addition, a partitioning convex piece 46d is formed on the winding partition flange 46 separating the first main winding portion 45a and the first sub-winding portion 45b as a convex portion protruding outward from the outer edge end of the winding partition flange 46 formed within the range of the first main winding portion 45a (see Figure 2C The partition convex piece 46d can play a role in positioning the bobbin cover 50.

[0162] Moreover, in this embodiment, the gap retaining piece 52a is intermittently formed along the circumferential direction on the outer peripheral edge of the lower flange portion 52 of the bobbin cover 50, the first sub-winding portion 45b is located inside the gap retaining piece 52a, and the flange-shaped coil portion 20a is formed inside the gap retaining piece 52a. With this configuration, it is easy to wind a plurality of turns of the first winding 22 around the outer periphery of the first sub-winding portion 45b.

[0163] In addition, in the present embodiment, the first winding 22 is continuously α-wound in the first main winding portion 45a and the first sub-winding portion 45b. By setting it as α-winding, the winding of the first winding 22 becomes easy, and the axial length of the inner coil 20 formed by the first winding 22 can be shortened. In addition, it is easy to wind a plurality of turns of the first winding 22 around the outer periphery of the first sub-winding portion 45b.

[0164] Second embodiment

[0165] In addition to the points shown below, Figure 1B and Figure 5B The coil device 10A of the second embodiment shown has the same structure as the coil device 10 of the first embodiment, and exhibits the same operation and effects. Figure 1B and Figure 5B In the following description, the same reference numerals are used to denote the same components as those in the coil device 10 according to the first embodiment, and part of the description thereof will be omitted.

[0166] The coil device 10A of the present embodiment includes an insulating protection portion 100A. Figure 5A and Figure 5B By comparison, it can be seen that the insulation protection part 100A of this embodiment is different from the insulation protection part 100 of the first embodiment in that it is formed integrally with the lead-out block 490. The insulation protection part 100A and the lead-out block 490 are integrally formed by injection molding or the like.

[0167] like Figure 5B As shown in FIG. 1 , the insulating protection portion 100A has a housing cross-section portion 120A and an outer extension portion 130A, and has a substantially L-shaped shape. Figure 5A The structure of the inner extension portion 110 of the first embodiment shown in FIG. Figure 5B As shown, by integrating the insulating protection portion 100A with the lead wire lead-out block 490, the rear wall portion 490c of the lead wire lead-out block 490 plays the role of Figure 5A The illustrated medial extension 110 serves the same purpose.

[0168] like Figure 5B As shown, the housing cross-section 120A is formed larger than Figure 5A The housing cross-section 120 of the first embodiment shown is thick, and the housing cross-sections 91d and 92d of the terminals 91 and 92 are accommodated inside. That is, in this embodiment, the housing cross-sections 91d and 92d are embedded in the interior of the housing cross-section 120A and are not cut and exposed outside. The inner end of the housing cross-section 120A in the X-axis direction is integrally connected to the upper end of the rear wall 490c of the lead lead block 490 in the Z-axis direction. The lower surface of the housing cross-section 120A abuts against the upper opening edge 330 of the housing 300.

[0169] The outer extension portion 130A is formed larger than Figure 5A The outer extension portion 130 of the first embodiment shown is thick, and the lower extension pieces 91e and 92e of the terminals 91 and 92 are accommodated inside. That is, in this embodiment, the lower extension pieces 91e and 92e are embedded in the interior of the outer extension portion 130A and are not cut out and exposed outside. On the outer end surface of the outer extension portion 130A in the X-axis direction, two terminal holes 131 and 131 are formed at a predetermined interval along the Y-axis direction. Through the terminal holes 131 and 131, the outer protruding pieces 91f and 92f of the terminals 91 and 92 are led out. The inner end surface of the outer extension portion 130A in the X-axis direction abuts against the outer side surface 310 of the housing 300.

[0170] The insulating protection portion 100A is attached to the housing 300 by sandwiching the upper end portion of the housing 300 with the outer extension portion 130A and the rear wall portion 490 c of the lead-out block 490 .

[0171] In this embodiment, the same effect as in the first embodiment can be obtained. Moreover, in this embodiment, the insulating protection portion 100A is formed integrally with the lead wire lead-out block 490. Therefore, in the manufacturing process of the coil device 10A, the process of separately installing the insulating protection portion 100A (as a single body) on the housing 300 can be omitted, and the manufacture of the coil device 10A becomes easy.

[0172] In the present embodiment, the insulating protection portion 100A is formed integrally with the terminals 91 and 92. For example, the terminals 91 and 92 are integrally formed with the insulating protection portion 100A by insert molding or the like, thereby facilitating the manufacture of the coil device 10A.

[0173] The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present invention.

[0174] For example, in the above-mentioned embodiment, if Figure 3 As shown, the first sub-winding portion 45b is formed in the Z-axis direction of the first main winding portion 45a, and the flange-shaped coil portion 20a is formed on the lower side of the inner coil 20, but it can also be the opposite. That is, the first sub-winding portion 45b can also be formed in the Z-axis direction of the first main winding portion 45a, and the flange-shaped coil portion 20a is formed on the upper side of the inner coil 20. In this embodiment, since cooling is performed from the lower side of the housing 300, the flange-shaped coil portion 20a with a large number of radial winding layers is located on the lower side, and the heat dissipation is good.

[0175] In addition, the first winding 22 does not need to be α-winding, and can also be arranged winding. Even if it is arranged winding, the effect of the present invention can be expected. Moreover, the specific shape of the bobbin 40, 40a or the specific shape of the core 12 is not limited to the above-mentioned embodiment, and various changes can be made. In addition, the coil device of the present invention can also be used for reactors as well as transformers for chargers.

[0176] In the above-mentioned embodiments, the shape of the insulating protection part 100, 100A may be appropriately changed. Figure 5A In the embodiment, the inner extension portion 100 may be omitted from the insulating protection portion 100 to form the insulating protection portion 100 composed of the housing cross-cut portion 110 and the outer extension portion 130. Figure 5B In the embodiment, the insulating protection portion 100A and the lead wire lead-out block 490 may be separated.

[0177] In the above embodiments, the coil device 10, 10A may include two insulating protection parts 100, 100A, one insulating protection part 100, 100A insulates the terminal 91 from the housing 300, and the other insulating protection part 100, 100A insulates the terminal 92 from the housing 300.

[0178] In this case, the shape of the insulating protection portion 100 , 100A may be substantially identical to the shape of the housing cross-section pieces 91 d , 92 d and the downward extending pieces 91 e , 92 e of the terminals 91 , 92 .

[0179] Explanation of symbols

[0180] 10, 10A coil device

[0181] 12 cores

[0182] 13 Base

[0183] 14 Midfoot

[0184] 16 Side Foot

[0185] 20 Inner coil

[0186] 20a Flange-shaped coil portion

[0187] 22 First winding

[0188] 22a Lead wire

[0189] 30 Outer coil

[0190] 32 Second winding

[0191] 32a Lead part

[0192] 40 bobbins (transformer skeleton / bobbin)

[0193] 42 spool base plate

[0194] 42a Foot

[0195] 44 first hollow cylinder

[0196] 44a First through hole

[0197] 44b Separation convex portion

[0198] 45 First winding section

[0199] 45a First main winding portion

[0200] 45b First sub-winding portion

[0201] 46 Wrap around the bulkhead flange

[0202] 46a Connection slot

[0203] 46b, 46c: incision edge

[0204] 46d separation tab (convex part)

[0205] 46e Circulation Clearance

[0206] 47 Winding Division

[0207] 48 Spool upper flange

[0208] 48a Step

[0209] 48b Positioning recess

[0210] 48c Engagement protrusion

[0211] 49 Lead wire lead-out section

[0212] 490 Lead-out block (terminal block)

[0213] 490a Base

[0214] 490b Front wall

[0215] 490c rear wall

[0216] 490d Side wall

[0217] 490e Vertical Exit Slot

[0218] 490f Horizontal outlet trough

[0219] 490g snap-fit ​​protrusion

[0220] 490h Fixed convex part

[0221] 490i Groove

[0222] 491 Lead wire lead platform

[0223] 491a Center of base

[0224] 491b Base side

[0225] 491c Base lead-out slot

[0226] 491d Side thin plate

[0227] 491e Insulation Wall

[0228] 491f Fixing recess

[0229] 50 Spool Cover

[0230] 50a, 50b half body

[0231] 52 Flange portion under cover

[0232] 52a Gap retaining sheet (non-winding portion)

[0233] 52b Opening

[0234] 53 Split connection

[0235] 53a Inner connecting piece

[0236] 53b Outer connecting piece

[0237] 54 Second hollow cylinder

[0238] 55 Second winding section

[0239] 58 Cover flange

[0240] 58a Connecting upper flange

[0241] 58b Connecting lower flange

[0242] 58c, 58d: engagement portion

[0243] 58e, 58f engagement surface

[0244] 58g, 58h Step convex part

[0245] 58i Stop boss

[0246] 60 Core cover

[0247] 62 Cover body

[0248] 62a Split piece

[0249] 64 Mounting flange

[0250] 64a Protruding piece

[0251] 64b Opening

[0252] 66 Insulation board

[0253] 66a Engagement protrusion

[0254] 70 Lead block cover

[0255] 71 Top plate

[0256] 72 Side wall

[0257] 73 Rear wall

[0258] 74 recess

[0259] 80 heat sink

[0260] 91, 92 terminals

[0261] 91a, 92a Lead connection piece

[0262] 91b, 92b Side extensions

[0263] 91c, 92c upper extension piece

[0264] 91d, 92d shell cross section

[0265] 91e, 92e lower extension piece

[0266] 91f, 92f Outer protrusion

[0267] 100, 100A insulation protection part

[0268] 110 Medial extension

[0269] 120, 120A Shell cross section

[0270] 130, 130A Outer extension

[0271] 200 Insulation Board

[0272] 210 Plate body

[0273] 220 Plate top plate

[0274] 230 Outer plate protrusion

[0275] 240 Lead Path

[0276] 300 Shell

[0277] 305 Frame

[0278] 310 outer side

[0279] 320 inner side

[0280] 315, 330 Open edge

[0281] 340 Base Plate

[0282] LS resin above.

Claims

1. A coil device, comprising: a bobbin having a first winding portion for winding a first winding wire around an outer circumference; and a bobbin cover covering the periphery of the bobbin around which the first winding wire is wound, It is characterized in that The bobbin cover includes a second winding portion for winding a second winding wire different from the first winding wire around an outer circumference, and a non-winding portion arranged at a lower position or an upper position along an axial direction of the second winding portion. The number of sub-winding layers of the first winding wound in the first sub-winding portion of the first winding portion located inside the non-winding portion is greater than the number of main winding layers of the first winding wound in the first main winding portion of the first winding portion located inside the second winding portion.

2. The coil device according to claim 1, It is characterized in that The position of the outermost peripheral layer of the first winding wound on the first sub-winding portion is located outside the cylindrical wall of the second winding portion.

3. The coil device according to claim 1 or 2, It is characterized in that When viewed from the axial direction, the first winding wound on the first sub-winding portion and the second winding wound on the second winding portion overlap.

4. The coil device according to claim 1, It is characterized in that The first winding portion has winding partition wall flanges formed at predetermined intervals along the axial direction. A convex portion that protrudes outward from an outer edge end of the winding partition wall flange formed within the range of the first main winding portion is formed on the winding partition wall flange that separates the first main winding portion from the first sub-winding portion.

5. The coil device according to claim 4, It is characterized in that The protrusion forms a cutout, and the cutout forms a flow gap penetrating in the axial direction.

6. The coil device according to claim 1, It is characterized in that The spool cover has: A second hollow cylindrical portion constituting the second winding portion; and a pair of cover flange portions formed at both ends of the second hollow cylindrical portion in the axial direction, A plurality of gap retaining pieces constituting the non-winding portion are intermittently formed along the circumferential direction on the outer periphery of at least any one of the cover flange portions. The first sub-winding portion is located inside the gap maintaining sheet.

7. The coil device according to claim 6, It is characterized in that An opening portion connecting the outer side and the inner side of the gap maintaining piece is formed on the gap maintaining piece.

8. The coil device according to claim 1, It is characterized in that The first winding wire is wound around the first main winding portion and the first sub-winding portion α.

9. The coil device according to claim 1, It is characterized in that A housing is further provided, wherein the housing contains a highly thermally conductive resin so that the first winding portion of the bobbin and the second winding portion of the bobbin cover are filled with the highly thermally conductive resin.

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