TWI484510B - Inductance element - Google Patents

Description

Inductive component

The present invention relates to an inductive component in which a coil is embedded in a magnetic core, and more particularly to an insulation withstand voltage between a terminal portion and a magnetic core.

Patent Document 1 discloses an invention in which a low dielectric constant resin film is disposed between an external electrode and a coil conductor to suppress generation of impurities between the external electrode and the coil conductor. Bulk capacitor.

In Patent Document 2, a composite member made of a ferromagnetic metal powder and a resin is formed into a rectangular parallelepiped, a resin is impregnated on the surface of the composite member, a through hole is formed in the composite member, and a signal line is formed in the through hole. conductor. Further, a terminal conductor is formed from the surface of the composite member impregnated with the resin to the surface of the exposed signal conductor.

Further, Patent Document 3 discloses an invention of a coil component that leads a terminal from a coil to a back surface of a core and places an insulating sheet between a core and a terminal.

Further, Patent Document 4 discloses an invention of an inductor which leads a terminal from a coil to a back surface of a core and removes an insulating layer of the terminal.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. Hei 9-246046

[Patent Document 2] Japanese Patent Laid-Open No. Hei 9-82528

[Patent Document 3] Japanese Patent Laid-Open No. Hei 10-223450

[Patent Document 4] Japanese Patent Laid-Open Publication No. 2006-13066

However, the front end of the terminal portion extending from the coil to the back surface of the magnetic core is a cut surface, and an insulating film is not provided, so that the conductor is exposed. Therefore, there is a problem that the insulation withstand voltage between the front end of the terminal portion and the magnetic core opposed to the front end is lowered.

In each of the above patent documents, the insulation withstand voltage between the front end of the terminal portion and the magnetic core is not described.

Accordingly, the present invention has been made in view of the above problems, and an object thereof is to provide an inductance element capable of improving the insulation withstand voltage between the front end of the terminal portion and the magnetic core, in particular, compared with the prior art.

The invention provides an inductive component which is embedded in a coil inside a magnetic core, and is characterized in that one end extending from the coil is bent on an end portion of the conductive strip body, and the outer surface of the magnetic core is bent Forming a pair of terminal portions; the surface of the conductive tape body is covered by the first insulating layer except for the front end of the terminal portion; and a gap is provided between the front end of the terminal portion and the magnetic core facing the front end, and The gap is filled with a second insulating layer. Thereby, the insulation withstand voltage between the front end of the terminal portion and the magnetic core can be effectively improved as compared with the prior art. In the present invention, it is preferable that the second insulating layer is formed on the surface of the magnetic core and the surface of the first insulating layer together with the gap, and penetrates one of the first insulating layer and the second insulating layer. a through hole for exposing a surface of the conductive strip body of the terminal portion is formed in the laminated portion, and a pair of terminal conducting portions are formed from a surface of the second insulating layer to the through hole. The terminal portion and the terminal conduction portion are electrically connected to each other through the through hole. Thereby, the insulation withstand voltage between the terminal conducting portion and the magnetic core can be improved, and the terminal portion and the terminal conducting portion can be appropriately electrically connected.

In the above aspect of the invention, preferably, the first insulating layer covers an electrically insulating coating resin layer on a surface of the conductive tape, and the second insulating layer serves as an insulating coating on a surface of the magnetic core. A protective resin layer of electrical insulation of the material. Thereby, it is possible to stably obtain high insulation withstand voltage at low cost without making the manufacturing complicated.

Further, in the invention, it is preferable that at least the first insulating layer is not provided on the front end surface of the terminal portion, and at least the front end surface and the side wall of the magnetic core facing the front end are formed. gap. Since the front end surface of the terminal portion is the cut surface of the covered wire, the conductive tape body is exposed on the front end surface. Therefore, by providing a gap between the front end surface of the terminal portion and the side wall of the magnetic core, and embedding the second insulating layer in the gap, the insulation withstand voltage can be appropriately increased.

According to the inductance element of the present invention, the insulation withstand voltage between the front end of the terminal portion and the magnetic core can be effectively improved as compared with the prior art.

1‧‧‧Inductive components

10‧‧‧ coil

11‧‧‧Electrical belt

11a‧‧‧ board

11b‧‧‧ side end face

12‧‧‧coated resin layer (first insulating layer)

13‧‧‧1st end

14a, 17a‧‧‧1st line

14b, 17b‧‧‧ 2nd fold line

14c, 17c‧‧‧3rd line

14d, 17d‧‧‧ 4th line

15‧‧‧1st terminal part

16‧‧‧2nd end

18‧‧‧2nd terminal section

20‧‧‧ magnetic core

20a‧‧‧ recess

20b, 20c‧‧‧ sidewall of magnetic core 20

21‧‧‧ upper surface

22‧‧‧Lower surface (back)

23‧‧‧ side

24‧‧‧ front end

25, 45, δ‧‧‧ gap

26‧‧‧ front end

30‧‧‧ Pressing machine

31‧‧‧Mold body

32‧‧‧Down

33‧‧‧上模

34‧‧‧ cavity

40‧‧‧Protruding

41‧‧‧Protective resin layer (2nd insulating layer)

42‧‧‧Terminal Conduction

43‧‧‧through holes

A‧‧‧Size in the width direction

B‧‧‧Dimensions in the thickness direction

C‧‧‧ arrow

D‧‧‧ face to face area

E‧‧‧ between the front end 26 and the opposite direction of the height direction (thickness direction) of the recess 20a

F‧‧‧Adding pressure

O‧‧‧ winding centerline

Fig. 1 is a perspective view showing a state in which a coil used in an inductance element according to an embodiment of the present invention is wound and formed.

Fig. 2 is a perspective view showing a state in which a terminal portion is bent and formed in a coil.

Figure 3 is a rear view of the inductive component.

4 is a cross-sectional view of the inductor element, and is a cross-sectional view taken along line IV-IV of FIG. 2.

Fig. 5 is a partially enlarged cross-sectional view showing a portion of Fig. 4 in an enlarged manner.

Fig. 6 is a partially enlarged longitudinal sectional view showing a portion different from Fig. 5.

Fig. 7 is a partially enlarged longitudinal sectional view showing a portion different from Fig. 5.

Fig. 8 is a partially enlarged longitudinal sectional view showing a comparative example.

Fig. 9 is a rear view showing the inductance element in a state where the terminal conducting portion is not formed.

Figure 10 is a rear elevational view of a portion of the inductive component that is different from Figure 9.

Figure 11 is a side view showing the process of powder press forming a magnetic core.

Fig. 12 is a partially enlarged longitudinal sectional view showing the vicinity of a terminal portion when the magnetic core shown in Fig. 11 is subjected to powder press molding.

In the inductance element 1 of the embodiment of the present invention, the coil 10 is embedded in the magnetic core 20 as a powder press molded body. In FIG. 2, the coil 10 embedded in the magnetic core 20 is indicated by a solid line, and the outer surface of the magnetic core 20 is indicated by a broken line.

As shown in FIGS. 1 and 2, the coil 10 is formed by winding a conductive tape body 11. As shown in Fig. 1 and Fig. 2 and the like, the conductive tape body 11 has a strip-shaped body having a rectangular cross section in the opposing plate faces 11a and 11a and the opposite side end faces 11b and 11b. As shown in FIG. 2, the dimension A in the width direction is sufficiently larger than the dimension B in the thickness direction, and the dimension A is twice or more, preferably 6 times or more, the dimension B.

The conductive tape body 11 is made of copper, and the coating resin layer 12 is formed on the surface of the conductive tape body 11 as shown in FIG. 5 and the like below.

The winding center line O of the coil 10 is shown in Figs. The coil 10 is wound in such a manner that the plate surface 11a of the conductive strip 11 is substantially perpendicular to the winding center line O, and the direction in which the side end surface 11b in the thickness direction is parallel to the winding center line O is determined, and the plate faces 11a are along each other. The winding center line O overlaps. As shown in FIGS. 1, 2, and 3, the coil 10 is wound such that the conductive strip 11 is elliptical. Further, although the coil 10 is elliptical in FIGS. 1 to 3, it may be a perfect circle and may be appropriately selected by the manufacturer.

As shown in FIG. 1, in a state in which the coil 10 is wound in an elliptical shape, the first end portion 13 and the second end portion 16 of the conductive tape body 11 protrude from the coil 10. Here, the end portions 13 and 16 guide the both end portions of the electrical tape body 11 that are not wound into the coil 10.

As shown in Fig. 2, the first end portion 13 is bent in the valley direction by the first fold line 14a. The right angle is bent at a substantially right angle in the direction of the mountain by the second folding line 14b, and is bent at a substantially right angle in the valley folding direction at each of the third folding line 14c and the fourth folding line 14d. The second end portion 16 is bent at a substantially right angle in the direction of the mountain fold at the first fold line 17a, and is bent at a substantially right angle in the valley folding direction at the second fold line 17b, the third fold line 17c, and the fourth fold line 17d.

The portion of the first end portion 13 closer to the end than the fourth folding line 14d is the first terminal portion 15, and the portion of the second end portion 16 closer to the end than the fourth folding line 17d is the second terminal portion 18.

As shown in FIG. 2 and FIG. 4, the first terminal portion 15 is located slightly away from the plate surface 11a of the conductive strip 11 wound around the coil 10, and the plate of the conductive strip 11 of the first terminal portion 15 is formed. The surface 11a faces the plate surface 11a of the conductive strip 11 constituting the coil 10 substantially in parallel.

As shown in FIG. 2, the second terminal portion 18 is also located slightly away from the plate surface 11a of the conductive strip 11 wound around the coil 10, and the surface of the conductive strip 11 of the second terminal portion 18 is formed. 11a is opposed to the plate surface 11a of the conductive strip 11 constituting the coil 10 substantially in parallel.

Further, the upper end surface 11a of the first terminal portion 15 in FIG. 2 and the second terminal portion 18 are substantially flush with the upper surface 11a of FIG. 2, and the surface is perpendicular to the winding center line O. The face.

In the case where the inductance element 1 is provided on a printed circuit board (not shown), the terminal portions 15 and 18 are directed downward, and thus the upper side of each of FIGS. 2, 4, and 5 to 8 is formed. The surface corresponds to the surface of the lower surface (back surface) in a state of being placed on the printed substrate.

As shown in FIGS. 2 and 3, the magnetic core 20 as a powder press molded body has a top surface 21 and a lower surface (back surface) 22 and further has a cubic shape of four side faces. As shown in FIG. 2, FIG. 3, and FIG. 4, the first terminal portion 15 formed by the end portions 13 and 16 of the conductive strip 11 extending from the coil 10 and the surface 11a of the surface of the second terminal portion 18 are formed. In FIG. 2 and FIG. 4, the upper surface 11a) is exposed on the lower surface 22 of the core 20, and the surface 11a on the surface side of each of the terminal portions 15, 18 is substantially flush with the lower surface 22 of the core 20.

Further, as shown in FIG. 2, the plate surface 11a of the portion between the fold line 14c of the first end portion 13 of the conductive strip 11 and the fold line 14d is exposed on one side surface 23 of the magnetic core 20. Moreover, the second end portion 16 The plate surface 11a of the portion between the fold line 17c and the fold line 17d is also exposed on the side surface 23 of the magnetic core 20. Each of the plate faces 11a and the side faces 23 are substantially flush with each other.

4 and 9 (FIG. 9 is a rear view in which the terminal conducting portion 42 is removed from FIG. 3), the terminal portions 15, 18 are disposed on the lower surface 22 of the magnetic core 20 and the shape of the terminal portion. The recess 20a is formed in substantially the same shape. As shown in FIG. 11 below, the concave portion 20a is a magnetic core material that is supplied to the inside of the cavity 34 by a pressing force F in a state in which the coil 10 and the terminal portions 15, 18 are disposed inside the cavity 34. Formed when pressurized. In other words, in the formation of the molded body, the periphery of each of the terminal portions 15, 18 is surrounded by the core material in addition to the plate surface 11a on the surface side of each of the terminal portions 15, 18, thereby forming the concave portion 20a. Alternatively, the concave portion 20a may be formed in advance on the lower surface 22 of the magnetic core 20 before the formation of the terminal portions 15, 18, and the end portions 13 and 16 extending from the coil 10 may be bent to arrange the terminal portions 15 and 18 in the concave portion. Within 20a.

As shown in FIG. 5, the pair of terminal portions 15 and 18 (the second terminal portion 18 is not shown in FIG. 5, but the second terminal portion 18 has the same cross-sectional structure as the first terminal portion 15, so the following The terminal portions 15 and 18) are composed of a conductive tape body 11 and a coating resin layer (first insulating layer) 12 formed on the surface of the conductive tape body 11. The coating resin layer 12 is a two-layer structure in which a fusion layer such as nylon is laminated on the surface of the insulating resin layer, for example.

The coating resin layer 12 is formed on the upper surface and the lower surface of the conductive tape body 11 shown in Fig. 5, that is, the plate surface 11a and the side end surface 11b (see Fig. 9 and the like). Although not shown, the coating resin layer 12 is also formed on the surface of each of the conductive strips 11 of the coil 10 shown in Figs. 1, 2, and 4, so that the coating resin layer 12 is interposed between the respective constituents of the coil 10. The belt body 11 is.

As shown in FIG. 5, the coating resin layer 12 is not formed on the front end surface 24 of each of the terminal portions 15, 18. This is because the front end surface 24 corresponds to the cut surface when the covered wire is cut. Further, the front end surface 24 is defined as a region slightly retracted from the front end portion 26 of each of the terminal portions 15, 18, and the plate surface 11a and the side end surface 11b constituting the front end 26 of each of the terminal portions 15, 18 may not be formed. The structure of the resin layer 12 is covered. In the present specification, the front end portions 26 of the terminal portions 15, 18 are It may be referred to only as the front end surface 24, or may be an area including a position slightly retracted from the front end surface 24. The front end portions 26 of the terminal portions 15 and 18 are set to an area of 1/4 or less with respect to the extension length of the terminal portions 15 and 18 extending to the back surface 22 of the magnetic core 20 shown in Fig. 9, for example, and are preferably set to Areas below 1/10.

As shown in FIGS. 5 and 9, the front end surface 24 of each of the terminal portions 15 and 18 and the side wall 20b of the magnetic core 20 opposed to the front end surface 24 in the planar direction (the direction orthogonal to the front end surface 24) A gap 25 is formed therebetween. The gap 25 is a space region continuous with the recess 20a. Alternatively, as shown in FIG. 10, the gap 25 may be opposed to the side wall surface 11b of each of the terminal portions 15, 18 from the front end surface 24 of each of the terminal portions 15, 18 and the side wall 20b of the magnetic core 20, and the side wall surface 11b. Formed between the side walls 20c of the magnetic core 20. The structure of Fig. 10 is applied to a configuration in which the coating resin layer 12 is not formed at the end 26 of the front end portion 24 of each of the terminal portions 15 and 18 to the region slightly retracted therefrom. Further, the gap 25 can be formed not only at the position of the front end 26 of each of the terminal portions 15, 18 but also continuously from the front end 26 to the rear end.

As shown in FIGS. 4 and 5, the protective resin layer 41 (second insulating layer) is filled in the gap 25. The protective resin layer 41 is applied to the entire area of the outer surface of the magnetic core 20. Similarly to the coating resin layer 12, the protective resin layer 41 is an electrically insulating resin layer. The material of the protective resin layer 41 is not particularly limited, and examples thereof include polyimine or epoxy resin. Further, the protective resin layer 41 is preferably a resin which can be impregnated on the outer surface of the magnetic core 20.

Further, as shown in FIGS. 3, 4, and 5, a pair of terminal conducting portions 42 are formed on the lower surface 22 (surface on the lower surface side) of the magnetic core 20. As shown in FIG. 5, the terminal conducting portion 42 faces the magnetic core 20 via the protective resin layer 41. Moreover, as shown in FIG. 5, the terminal conduction portion 42 and the conductive tape body 11 constituting the terminal portions 15 and 18 are opposed to each other except for a laminated structure of the coating resin layer 12 and the protective resin layer 41.

As shown in FIG. 3 and FIG. 5, between the terminal conducting portion 42 and the conductive strip 11 constituting the terminal portions 15 and 18, the coating resin layer 12 and the protective resin layer 41 are penetrated in the thickness direction (height direction). Through hole 43. Thus, in FIG. 5, the protective resin layer 41 and the gap 25 are The surface of the magnetic core 20 and the surface of the coating resin layer 12 are formed, and a through hole 43 penetrating through the laminated portion of the coating resin layer 12 and the protective resin layer 41 is formed, and the surface of the conductive tape 11 (plate surface 11a) is formed. The through hole 43 is exposed. Further, the terminal conducting portion 42 enters the through hole 43, and the terminal conducting portion 42 is in contact with the conductive tape body 11. Thereby, the terminal conduction portion 42 is electrically connected to the conductive tape body 11 constituting the terminal portions 15 and 18.

Fig. 8 is a comparative example. In Fig. 8, a gap is formed between the front end surface 24 of each of the terminal portions 15, 18 and the side wall 20b of the magnetic core 20 opposed to the front end surface 24, and the conductive strip 11 and the magnetic body are formed. The core 20 is in contact at the location of the front end face 24.

The magnetic core 20 is, for example, a powder-molded molded body comprising a magnetic powder and a binder resin. In the comparative example of FIG. 8, the insulating layer is not maintained between the end faces 24 and the magnetic core 20 before the terminal portions 15 and 18. That is, the insulation withstand voltage is lowered. On the other hand, in the embodiment shown in FIG. 5, a gap 25 is formed between the end surface 24 of the terminal portions 15, 18 and the side wall 20b of the magnetic core 20, and the gap 25 is filled with the electrically insulating protective resin layer 41. Therefore, the insulation withstand voltage between the front end surface 24 exposed by the conductive strip 11 and the side wall 20b of the magnetic core 20 can be effectively improved as compared with the comparative example shown in FIG. Further, if the configuration shown in Fig. 10 is adopted, a gap 25 is formed between the side wall surface 11b of the front end portion 26 of the terminal portions 15, 18 and the side wall 20c of the magnetic core 20, and the gap 25 is filled with protection. Since the resin layer 41 is in a form in which the coating resin layer 12 is not formed at the end 26 before the front end surface 24 is slightly retreated, the insulation withstand voltage can be effectively improved.

Further, by impregnating the protective resin layer 41 with the outer surface of the magnetic core 20 and the gap 25, the resin penetrates into the gap 25 by capillary action, and the protective resin layer 41 can be appropriately buried in the gap 25. Further, by using the same resin embedded in the gap 25 as the insulating coating material on the outer surface of the magnetic core 20, the inside of the gap 25 can be buried by the resin in a low-cost and simple manufacturing method.

Further, as shown in FIG. 5, by interposing the protective resin layer 41 between the magnetic core 20 and the terminal conducting portion 42, the withstand voltage between the magnetic core 20 and the terminal conducting portion 42 can be improved. Again, as shown in Figure 5. As shown in the figure, the protective resin layer 41 is formed on the surface of each of the terminal portions 15, 18, but the through-coating resin layer 12 and the protective resin layer 41 are formed in the conductive portion between the terminal portions 15, 18 and the terminal conducting portion 42. The through hole 43 having the laminated structure allows the conductive strip 11 constituting the terminal portions 15 and 18 to be appropriately electrically connected to the terminal conducting portion 42 via the through hole 43. The through hole 43 is formed at a position that is retracted rearward from the front end surface 24 of each of the terminal portions 15 and 18 by a specific size. Thereby, the laminated structure of the coating resin layer 12 and the protective resin layer 41 remains between the through hole 43 and the front end surface 24 of each of the terminal portions 15 and 18 and at a position further rearward than the through hole 43. As shown in FIG. 3, the through hole 43 is smaller than the width dimension of the terminal portions 15, 18, and the through hole 43 is formed in a size accommodated in the region of the terminal portions 15, 18 in the arrow of FIG. Therefore, the terminal portions 15 and 18 and the terminal conduction portion 42 can be appropriately electrically connected via the through hole 43 , and the terminal conduction portion 42 and the magnetic core 20 can be appropriately ensured by the insulating resin layer extending around the through hole 43 . Insulation between.

This embodiment does not limit the method of forming the gap 25, and for example, the gap 25 can be formed by springback. The rebound will be described below using FIG.

The step of forming the magnetic core 20 into a powder press-formed body is shown in FIG.

The press machine 30 shown in Fig. 11 is provided with a lower mold 32 inside the mold body 31, and a cavity 34 is formed thereover. The coil 10 shown in FIG. 2 is inserted into the cavity 34, and the plate surface 11a of the surface of the first terminal portion 15 and the plate surface 11a of the surface of the second terminal portion 18 abut against the upper surface of the lower mold 32. Way to locate.

Thereafter, a core material containing a magnetic powder and a binder resin is supplied to the inside of the cavity 34. The magnetic powder-based magnetic alloy powder is, for example, a powder of a Fe-based amorphous alloy containing Fe, which is mainly composed of various metals such as Ni, Sn, Cr, P, C, B, and Si, and is powdered by a water mist method. The binder resin is a polysiloxane resin or an epoxy resin.

The core material is a mixed powder obtained by coating the magnetic powder with the binder resin. Alternatively, it may be a simple mixture of a magnetic powder and a powdery binder resin. Further, the core material may be temporarily formed in advance and inserted after being combined with the coil 10. Inside the cavity.

When the core material is filled into the cavity 34, the upper mold 33 is inserted from above the cavity 34, and the cavity 34 is heated, and the core material is subjected to the pressing force F by the lower mold 32 and the upper mold 33. The pressure is applied to form a magnetic core 20 as a powder press molded body. In the powder press molding, the binder resin functions as a binder for binding magnetic powders to each other. Further, heating is not necessarily required at the time of pressurization, and pressurization may be performed at room temperature.

As shown in FIG. 11, in the cavity 34, a core material containing a magnetic powder and a binder resin is pressurized between the lower mold 32 and the upper mold 33 by a pressing force F, and the coil 10 and the first terminal portion 15 are simultaneously pressed. The second terminal portion 18 is also pressurized by the pressing force F.

As shown in FIGS. 3 and 4, the first terminal portion 15 and the second terminal portion 18 have a face-to-face area D in which a part of the first terminal portion 15 faces the plate surface 11a of the conductive strip 11 on which the coil 10 is formed. As shown in Fig. 4, in the face-to-face area D, the gap δ between the terminal portions 15, 18 and the coil 10 is narrowed, and after the press forming, under the action of the resilience to separate the terminal portions 15, 18 from the coil 10 The magnetic core 20 in the region where the gap δ is narrow is liable to generate internal stress. Thereby, as shown in FIG. 9, between the end faces 24 of the respective terminal portions 15, 18 and the side walls 20b of the magnetic core 20, or as shown in FIG. 10, the front ends 26 of the respective terminal portions 15, 18 and the magnetic core 20 A rebound-based gap 25 is easily formed between the side walls 20c.

By adjusting the pressing force F or adjusting the heating temperature (annealing temperature) or the like, a repulsive force is appropriately generated, whereby a gap 25 of a moderate size can be formed. Here, the size of the gap 25 is not particularly limited as long as the insulation between the front end 26 of the terminal portions 15 and 18 and the side wall of the magnetic core 20 is ensured by interposing the protective resin layer 41, but the gap 25 is formed. When the thickness is too large, the strength of the magnetic core 20 is lowered. Therefore, the width of the gap 25 is preferably set to be about 100 μm or less (the width dimension of the longitudinal direction of the inductance element 1 is several tens of mm). For example, a mixed material of a powder of a Fe-based amorphous alloy and a binder resin is used as the core material, and the pressing force F is set to about 780 to 1180 MPa, and the heating temperature is set to about 350 to 450 °C.

Further, as shown in FIG. 12, for example, a mold having a projection 40 under the surface may be used. 32. As shown in FIG. 12, the protruding portion 40 is located just before the front end surface 24 of the terminal portions 15, 18, and the front end portion 24 and the magnetic core can be formed in front of the respective terminal portions 15, 18 without the position of the protruding portion 40 being buried by the core material. A gap 25 is formed between 20. Further, the protrusion 40 may be formed to surround the periphery of the front end 26 of the terminal portions 15, 18, and a gap 25 surrounding the front end 26 of the terminal portions 15, 18 may be formed as shown in FIG.

Alternatively, after the magnetic core 20 is subjected to powder press molding, the magnetic core 20 around the front end 24 of the terminal portions 15 and 18 or the front end 26 of the terminal portions 15 and 18 may be removed by laser or the like to form the gap 25.

6 and 7 are partial enlarged cross-sectional views of a portion different from Fig. 5. In FIG. 6, the front end 26 of each of the terminal portions 15, 18 is in a state of being floated in a direction separating from the inside of the concave portion 20a of the magnetic core 20. Compared with FIG. 5, since the front end 26 of each of the terminal portions 15, 18 is spaced apart from the magnetic core 20, the insulation withstand voltage between the front end 26 of each of the terminal portions 15, 18 and the magnetic core 20 can be more effectively improved.

In the form of Fig. 6, the front end face 24 of the terminal portions 15, 18 and the side wall 20b of the magnetic core 20 are also in an opposing positional relationship in the arrow C viewed from a direction perpendicular to the plane.

Further, as shown in FIG. 6, when the front end portion 24 of the terminal portions 15 and 18 faces the rear end portion 26 without forming the resin layer 12, the front end 26 is bent and floated in the concave portion 20a as shown in FIG. Thereby, the coating resin layer 41 can also be interposed between the opposing faces E in the height direction (thickness direction) of the front end 26 and the concave portion 20a. Thereby, the insulation withstand voltage between the tip end 26 and the magnetic core 20 can be more effectively improved.

Further, as shown in FIG. 7, a gap in which the side wall 20b is inclined such that the front end surface 24 of each of the terminal portions 15 and 18 and the side wall 20b of the magnetic core 20 gradually become larger toward the height direction of the terminal conducting portion 42 may be formed. 45. Further, a gap 45 similar to that of FIG. 7 can be formed between the side end surface 11b of the front end 26 of each of the terminal portions 15, 18 and the side wall 20c of the magnetic core 20 (see FIG. 10). If the gap 45 shown in FIG. 7 is the same volume as the gap 25 shown in FIG. When formed, the gap 45 of FIG. 7 can be enlarged laterally with respect to the gap 25 of FIG. 5, so that the inside of the gap 45 can be appropriately buried in the protective resin layer 41.

In the inductance element 1 shown in FIG. 2, FIG. 3, and the like, the pair of terminal portions 15 and 18 are provided on the lower surface (back surface) 22 of the magnetic core 20, but the terminal portions 15 and 18 are disposed on the magnetic core 20. Which one of the outer surfaces is not particularly limited.

Further, as shown in FIGS. 3 and 4, a pair of terminal conductive portions 42 are electrically connected to the pair of terminal portions 15 and 18, but the terminal conductive portion 42 is not necessarily formed. However, by providing the terminal conducting portion 42, the electrical connection between the inductor element 1 and the printed circuit board can be stabilized and good.

In the above description, the first insulating layer formed on the surface of the conductive tape 11 is made of the electrically insulating coating resin layer 12, and the second insulating layer of the buried gap 25 is made of an electrically insulating protective resin layer. 41, but the material of each insulating layer is not limited to the resin. However, when the coated wire is used, the first insulating layer is preferably coated with the resin layer 12. As the second insulating layer, an insulating material other than the resin can be buried in the gap 25 by sputtering or vapor deposition. However, the protective resin layer 41, which is an insulating coating material on the outer surface of the magnetic core 20, is used in the second insulating layer, and the gap 25 is buried by impregnation, whereby the gap 25 can be appropriately buried, and the manufacturing steps are not It is complicated and can suppress manufacturing costs.

11‧‧‧Electrical belt

11a‧‧‧ board

12‧‧‧coated resin layer (first insulating layer)

15‧‧‧1st terminal part

20‧‧‧ magnetic core

20a‧‧‧ recess

20b‧‧‧ sidewall of magnetic core 20

22‧‧‧Lower surface (back)

24‧‧‧ front end

25‧‧‧ gap

26‧‧‧ front end

41‧‧‧Protective resin layer (2nd insulating layer)

42‧‧‧Terminal Conduction

43‧‧‧through holes

Claims (4)

An inductor element in which a coil is embedded in a magnetic core, wherein one end extending from the coil bends an end portion of the conductive strip body to form a pair on the outer surface of the magnetic core a terminal portion; a surface of the conductive tape body covered by a first insulating layer except for a front end of the terminal portion; a gap is formed between the front end of the terminal portion and the magnetic core facing the front end, and is filled in the gap There is a second insulating layer. The inductance element according to claim 1, wherein the second insulating layer is formed on the surface of the magnetic core and the surface of the first insulating layer together with the gap; and penetrates one of the first insulating layer and the second insulating layer a through hole for exposing a surface of the conductive strip body of the terminal portion; a pair of terminal conducting portions formed from a surface of the second insulating layer to the through hole; and the terminal portion and the terminal conducting portion The conduction is conducted through the through hole. The inductance element according to claim 1 or 2, wherein the first insulating layer covers an electrically insulating coating resin layer on a surface of the conductive tape, and the second insulating layer serves as an insulating layer on a surface of the magnetic core An electrically insulating protective resin layer of the coating material. The inductance element according to claim 1 or 2, wherein the first insulating layer is not provided on at least the front end surface of the terminal portion, and the gap is formed at least between the front end surface and a side wall of the magnetic core facing the front end .