JP2019079974A - Coil component and on-vehicle electronic equipment comprising the same - Google Patents

Abstract

To provide a coil component capable of dealing with a high-density surface mounting step and of securing reliability requested as an on-vehicle component.SOLUTION: A coil component comprises: a compact 1 including magnetic powder and a binding agent; a coil 2 consisting of a conductor; and a box-like cover 3 consisting of an insulator. The coil is buried in the compact, and comprises terminal parts 2a and 2b protruded from a lateral face of the compact and directed toward a bottom face side of the compact, and further, bent along the bottom face. An adhesive member 4 is arranged at a clearance produced among the compact, the terminal parts, and the cover.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a coil component suitable for a power supply circuit of various electronic devices and an on-vehicle electronic device including the same.

  In recent years, with the development of in-vehicle electronic control technology, the number and places of use of various electronic devices mounted on vehicles such as automobiles are increasing, and downsizing and improvement in reliability of the electronic devices themselves are required. Some electronic components used in this type of electronic device are surface-mounted on a circuit board, and along with miniaturization for high-density mounting, heat resistance to solder reflow and in-vehicle use used under severe environmental conditions High durability and reliability unique to applications are required.

  As an electronic component that meets such requirements, there is a coil component such as a choke coil used in a power supply circuit or the like. In Patent Document 1, a coil made of a conductive material is embedded in a molded body made of a magnetic body, and the terminal portion of the coil protruding from the side surface of the molded body is bent along the bottom surface from the side surface of the molded body. The coil component of the structure by which at least one part of the clearance gap which arises in the opposing part of the side of a body and a terminal part is fixed by the adhesion member is disclosed.

JP, 2012-174815, A

  The coil component disclosed in Patent Document 1 has a configuration in which the terminal portion of the coil protruding from the side surface of the molded body is bent from the side surface to the bottom surface of the molded body. Reversion tends to occur, and when it occurs, a gap may occur between the molded body and the terminal portion. Then, if there is a gap between the molded body and the terminal portion, in the case of a coil component for in-vehicle use, if the frequency of vibration during traveling of the vehicle and the natural frequency of the coil component resonate, A large force is applied to the terminal, which may damage or break the bent portion.

  As an on-vehicle component, as a technology for improving resistance to vibration and impact, as in Patent Document 1, by fixing a part of the gap between the compact of the coil component and the terminal with an adhesive member, resonance of the terminal against vibration It is possible to suppress However, because only between the molded body and the terminal portion is fixed by the adhesive member, it is fixed to the molded body by the adhesive member depending on the environmental conditions such as temperature, humidity, vibration and impact assumed as an on-vehicle component There is a problem that the terminal portion may be peeled off and it is difficult to secure the long-term reliability of the coil component.

  Therefore, the present invention solves the problems of the prior art and can cope with a high density surface mounting process, and can also ensure the reliability required as an on-vehicle component, and an on-vehicle component comprising the same. It aims at providing an electronic device.

  According to the present invention, there is provided a molded body containing a magnetic powder and a binder, a coil made of a conductor, and a cover made of an insulator, the molded body having a bottom surface to be a mounting surface and an opposite side to the bottom surface. The coil is embedded in the molded body and protrudes from the side surface toward the bottom side and further along the bottom surface. The cover includes the terminal portion and the vicinity thereof at the side surface of the molded body and a part of the side surface of the molded body, and the cover includes the side surface of the molded body and the terminal portion. An adhesive agent is disposed in the gap between the terminal portion and the gap between the terminal portion and the cover, and the gap between the side surface of the molded body and the cover. .

  In the coil component of the present invention, the cover may further cover at least a part of the upper surface of the molded body.

  Further, in the coil component of the present invention, the cover may have a U-shaped shape which is bent from the upper surface to the side surface of the molded body and extended to the bottom surface side.

  Further, in the coil component of the present invention, the width of the cover in the U-shaped shape is preferably not less than the width of the terminal portion and not more than the width of the molded body on the side surface of the molded body.

  Further, in the coil component of the present invention, the cover may have a box shape covering the upper surface and the side surface of the molded body.

  Further, in the coil component of the present invention, it is a U-shaped fixed member extending along the outer surface of the cover toward the bottom side of the formed body, and further including a terminal portion along the bottom side of the formed body It is desirable to further provide a holding member.

  Further, in the coil component of the present invention, the width of the fixing member may be wider than the terminal portion of the fixing member so as not to exceed the side surface of the molded body.

  Further, in the coil component of the present invention, the fixing member may be a metal fixing fitting, and may have an annular portion having a through hole at a portion in contact with the upper surface of the cover.

  Further, in the coil component of the present invention, the terminal portion of the coil and the terminal portion of the fixing bracket can be used as soldered portions of the mounting surface.

  Further, in the coil component of the present invention, it is desirable that a plurality of rib portions be provided on the inner surface of the cover facing the molded body.

  According to the present invention, there is also provided an on-vehicle electronic device provided with the above-described coil component.

  According to the present invention, it is possible to prevent the occurrence of resonance of the vibration that causes a large stress in the terminal part of the coil component, and to suppress the occurrence of cracks and breakage in the bent part of the terminal part.

  In addition, since the area to which the bonding member adheres can be made larger than the surface area of the terminal portion compared to the coil component of the conventional configuration, the stress applied to the bonding portion by the vibration is alleviated and peeling at the bonding interface occurs. It becomes difficult.

  When the fixing bracket is provided, the cover can be fixed more firmly on the mounting substrate by the fixing bracket, so that the cover can be prevented from coming off even when a strong impact is applied. Further, by soldering the end portion of the fixing bracket to the mounting substrate, the fixing becomes stronger and peeling from the surface of the mounting substrate due to vibration can also be suppressed.

  When the cover has a box shape, the surface area of the cover is larger than the surface area of the molded product, so that there is also an effect of improving the heat dissipation and reducing the temperature rise. In addition, since the area of the surface of the molded body exposed to the air is reduced, rusting is less likely to occur on the surface of the molded body. Since the adhesive member is sufficient only to be interposed between the cover and the molded body, the amount of adhesive used can be reduced.

  When the fixing bracket is provided, by making the fixing bracket in contact with the upper surface of the cover an annular portion, the leakage flux from the molded body is attenuated by the eddy current loss, and the electromagnetic noise radiated to the outside from the coil component The electronic control device can be reliably operated by reducing the size and downsizing the arrangement between the parts.

1 is a see-through perspective view of a first embodiment of a coil component according to the invention; It is a longitudinal cross-sectional view by the AA 'line | wire of the coil components of FIG. Fig. 2 shows a perspective view of a second embodiment of a coil component according to the invention; It is a longitudinal cross-sectional view by the CC 'line | wire of the coil components of FIG. FIG. 7 is a perspective view of a third embodiment of a coil component according to the invention; It is a longitudinal cross-sectional view by the DD 'line | wire of the coil components of FIG.

  Hereinafter, some preferred embodiments and modifications of the coil component according to the present invention will be described in detail with reference to the drawings. In the following description, terms indicating directions such as “top”, “top”, “bottom”, etc. indicate relative directions depending only on the relative positional relationship of coil component parts, and vertical It does not indicate the absolute direction such as the direction. Further, it is needless to say that the configurations of the embodiments and the modifications described below are merely preferable examples, and the present invention is not meant to be limited to these configurations.

First Embodiment
A first embodiment of a coil component according to the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a see-through perspective view of a first embodiment of a coil component according to the present invention, with the contents of the coil component shown for clarity. FIG. 2 is a longitudinal sectional view of the coil component of FIG. 1 taken along the line A-A '.

  In FIG. 1 and FIG. 2, the coil component 100 according to the first embodiment is embedded in a compact 1 (shown by a solid line) formed by mixing and pressing magnetic powder and a binder, and the compact 1. Interposed between the outer surface of the molded body 1 and the inner surface of the cover 3 (shown by a broken line), the cover 3 (shown by a two-dot chain line) made of an insulator accommodating the molded body 1 And an adhesive member 4. Here, the coil 2 made of a conductor is such that one end of the winding is taken out from the lower side of the coil side and connected to the joint portion of the terminal portion 2a by the conductive material, and the other end of the winding is the coil opposite to the terminal portion 2a It takes out from the upper part of a side, and is connected with the junction of terminal area 2b by a conductive material. Further, a part of the terminal portions 2a and 2b including the whole of the coil 2 and the joint portion between the winding and the terminal portions 2a and 2b is embedded in the molded body 1. Further, the terminal portion 2a protruding from the lower side of the side surface of the molded body 1 extends downward from the side surface of the molded body 1 and is bent so that the tip end portion follows the bottom surface of the molded body 1. On the other hand, the terminal portion 2b protruding from the side surface upper portion on the opposite side to the terminal portion 2a in the molded body 1 extends downward along the side surface of the molded body 1 and is bent so that the tip end follows the bottom surface of the molded body 1 It is giving. In addition, although the taking-out position of one end of a winding and the other end is made into the coil side lower part and the coil side upper part, respectively, this is only an example, and the taking-out position can be decided arbitrarily. Below, the part which follows the side of molded object 1 among terminal parts 2a and 2b may be called a terminal side part, and the part which follows the bottom of molded object 1 may be called a terminal bottom. In this case, the surface of the terminal side surface portion is defined by the inner surface facing the molded body 1, the outer surface facing the cover 3, and two side surfaces connecting these two surfaces.

  Here also, a structure is shown in which the winding end of the coil 2 is connected to the junction of the terminal portions 2a and 2b, but the winding end of the coil 2 may be used as it is as the terminal portions 2a and 2b. . Moreover, although it is desirable to form the recessed part 1a for receiving the terminal bottom face part of terminal part 2a, 2b in the bottom face of the molded object 1, you may abbreviate | omit. When the recessed portion 1a is provided, the height of the coil component 100 at the time of substrate mounting can be reduced, and the stability against vibration is enhanced.

  The cover 3 is made of an electrical insulator such as a liquid crystal polymer that can withstand high temperature during solder mounting, and is attached from the opposite side (upper side in FIG. 1) of the mounting surface of the molded body 1. In the cover 3, a plurality of rib portions 3 a having a projection length extending from the lower end to the top surface and substantially in contact with the side surface of the molded body 1 are provided on each inner surface facing the molded body 1. In particular, the upper end portion of the rib 3a corresponding to the upper surface of the molded body 1 has an inverted L shape so that a portion in contact with the upper surface of the molded body 1 can be formed. Thus, in addition to the side surface of the molded body 1, each rib portion 3 a also abuts on a part of the upper surface of the molded body 1. The shape of such a rib portion 3a is a preferable example, and the rib portion may not extend from the lower end of the inner surface of the cover 3 to the top surface, and may be partially disposed on the inner surface of the cover 3 .

  Here, of the four inner side surfaces of the cover 3, two rib portions 3a are provided on each of two inner side surface portions facing the terminal portions 2a and 2b, and three rib portions 3a are provided on the remaining two inner side surface portions. However, this is only an example and is not limited thereto. By providing such a rib 3a, a gap in which the bonding member 4 is accommodated can be secured. Further, since the gap between the molded body 1 and the cover 3 can be set by the protruding length of the rib portion 3a, the amount of adhesive used can be reduced. Furthermore, the reduction of the contact area between the molded body 1 and the cover 3 can reduce the frictional resistance when the cover 3 is attached, and the assembling work of the molded body 1 and the cover 3 can be smoothly performed. Moreover, as for each inner surface part of the cover 3 which opposes the molded object 1, it is desirable to make it uneven | corrugated on the surface by sandblasting etc. FIG. By doing this, the adhesiveness between the cover 3 and the bonding member 4 is increased, and it is possible to suppress the occurrence of peeling between the cover 3 and the bonding member 4 (interface).

  As shown in FIG. 2, it is desirable that the bottom surface of the cover 3 and the bottom surface of the molded body 1 be flush with each other, but the present invention is not limited thereto. In order to form the adhesive member 4 in the gap between the molded body 1 and the cover 3, introduction of an adhesive as described below is performed.

  The bonding member 4 may be formed by pressing the liquid or gel adhesive into the gap after combining the cover 3 and the molded body 1 with the upper surface side of the cover 3 facing down. Before combining, it is preferable to apply an adhesive to each inner surface of the cover 3 except the rib 3a and the surfaces of the molded body 1 and the terminal side surface of the terminal 2a, 2b opposite thereto. By doing this, the wettability of the adhesive with the inner surface of each cover 3 and the surface of the terminal side surface of the molded body 1 and the terminal portions 2a and 2b is improved, and the occurrence of adhesion failure can be suppressed. The material of the bonding member 4 is not particularly limited as long as it fixes the cover 3, the molded body 1 and the terminal portions 2a and 2b, but the space between the molded body 1 and the terminal side surface portion of the terminal portions 2a and 2b is not particularly limited. It is desirable that the viscosity is such that it can flow into the gap between By selecting the adhesive having such viscosity, the vibration from the terminal portion is widely dispersed through the inner surface, the outer surface and the two side surface regions of the terminal side portion to which the adhesive is applied. The adhesive strength between the molded body 1 and the molded body 1 is increased, and the terminal portions 2a and 2b can be prevented from peeling from the side surface of the molded body 1. As a result, the rigidity of the coil component 100 is less likely to be reduced, and natural vibrations are less likely to occur at low frequencies such as vehicle vibrations. It is preferable that the thermal expansion coefficient of the bonding member 4 be made close to the thermal expansion coefficient of the terminal portions 2a and 2b by including an appropriate amount of glass filler in the adhesive. For example, when the material of the terminal portions 2a and 2b is Cu, the thermal expansion coefficient of the bonding member 4 is set to the thermal expansion coefficient of the terminal portions 2a and 2b by mixing about 30 to 40% by volume of glass filler into the adhesive. It can be approached.

  The coil component according to the first embodiment of the present invention described above is a box made of a magnetic body powder and a binder, a compact formed by pressure molding with a binder, a coil embedded in the compact, and an insulator And a cover of The molded body has at least a bottom surface which is a mounting surface, and a side surface which is in contact with one side of an edge of the bottom surface. The coil includes two terminal portions protruding from the side surface of the molded body and bent along the bottom surface. The terminal portion includes a terminal side surface portion along the side surface of the molded body and a terminal bottom surface portion along the bottom surface of the molded body. The cover is combined with the molded body so as to cover the outer peripheral surface of the molded body other than the bottom surface, and the gap between the inner surface of the cover and the outer peripheral surface of the molded body including the terminal side surface portion adheres It is fixed by a member. In addition, the coil component is mounted by soldering two terminal bottom portions to a mounting substrate.

[Effect of First Embodiment]
A gap between the inner surface of the cover and the outer peripheral surface of the molded body, including the terminal side portion projecting from the molded body, is fixed by the adhesive member. As a result, even if there is a gap between the terminal side surface portion and the molded body, the adhesive flows into the space and the terminal portion and the molded body can be fixed. At the same time, since the terminal portion and the molded body are bonded and fixed via the cover, the rigidity of the coil component is less likely to decrease, and natural vibration is less likely to occur at low frequencies such as vehicle vibration. As a result, stress due to vibration applied to the bonding interface is alleviated, and peeling between the molded body and the bonding member, between the terminal side surface portion and the bonding member, and between the cover and the bonding member is less likely to occur.

  Since the surface area of the cover is larger than the surface area of the molded body, the heat dissipation is improved, and the effect of reducing the temperature rise due to the heat generation of the coil component can also be obtained. In addition, since the area of the surface of the molded body exposed to the air is reduced, rust is less likely to occur on the surface of the molded body.

  The natural vibration frequency is 2000 Hz or more and 9600 Hz or less, and can be higher than the frequency generated by the vibration of the vehicle. Therefore, the vibration force applied to the substrate does not include the directional component and frequency component inducing natural vibration, and the large stress due to resonance Will not occur.

  There is no natural vibration that causes a large stress in the terminal part of the coil component, and it is possible to suppress the occurrence of cracks and breakage at the bent part of the terminal part.

  The adhesive member intervenes over the entire surface of the terminal side surface, that is, the inner and outer surfaces of the terminal side surface and the entire two side surfaces, so that the area of the bonding portion on the terminal side surface can be made larger than in the conventional case. The stress due to the vibration applied to the interface is alleviated, and peeling between the terminal portion and the adhesive member is less likely to occur.

  By providing a plurality of rib portions 3 a extending from the lower end (bottom surface portion) to the top surface on the inner surface side of the cover 3, the molded body 1 can be positioned and arranged at a predetermined position inside the cover 3. As a result, unevenness or left-right difference does not occur between the surface of the molded body 1 and the inner surface of the cover 3, that is, the thickness of the bonding member 4, and partial difference or left-right difference does not occur in stress dispersion.

  In addition, the following example can be considered as a modification of 1st Embodiment mentioned above.

(First modification)
In the first embodiment, the shape of the cover 3 is in the form of a box which can cover the entire molded body 1. However, the cover is a plate-like insulator cover which is in the vicinity of the terminal portions 2a and 2b and has a width larger than the width of the terminal portions 2a and 2b and is arranged like a batten on the terminal portions 2a and 2b. It may be. In this case, the adhesive is applied to the gap between the molded body and the terminal portion (terminal side surface portion), the gap between the terminal portion (terminal side surface portion) and the plate-like cover, and the gap between the molded body and the cover By being introduced and solidified, the vibration of the terminal portion is dispersed to the adhesive member on the molded body side (inner side) and the adhesive member on the cover side (outer side). Specifically, by making the width of the cover larger than the width of the terminal portions 2a and 2b, the cover covers the terminal portion, particularly the terminal side surface portion and its vicinity, and a part of the side surface of the molded body. Since the two sides are covered with the adhesive in addition to the inner and outer surfaces of the part (terminal side part), not only the vibration from the terminal part is dispersed to both the inside and the outside but also the two sides It is dispersed inside and outside through the adhesive members. As a result, there is no cover, and the bonding member is provided only in the gap between the molded body and the terminal portion, and the stress is relieved more than in the case where only the inner side of the terminal portion is fixed.

  In addition to the terminal portions 2a and 2b, the cover may be two L-shaped covers covering at least a part of the side surface and the upper surface of the molded body, and the inner surface side of the cover has a rib portion It is good. Of course, the width of the cover is made wider than the width of the terminal portions 2a and 2b.

  According to the first modification, the adhesive may be sufficient only by being interposed between the plate-like cover and the molded body, including between the molded body and the terminal side face portion, and between the terminal side face portion and the cover. Therefore, the amount of adhesive used can be reduced compared to the first embodiment.

(Second modification)
Next, in place of the two L-shaped covers arranged like the above-mentioned batten, a U-shaped cover is used, and this cover is used as a terminal for the terminals 2a and 2b. A gap between the molded body 1 and the cover, a gap between the molded body 1 and the terminal side wall of the terminal portion 2a, 2b, and a terminal side wall of the terminal portion 2a, 2b after being assembled to face the side wall portion An adhesive may be introduced into the gap between the part and the cover to be solidified. The width of the U-shaped cover is wider than the width of the terminal portions 2a and 2b. In the second modified example, the presence of the U-shaped cover causes the upper surface of the cover to press the side surface portions of the terminals facing the two leg portions of the cover, which further strengthens adhesion. Moreover, since a cover becomes a patch which adheres a terminal part to the side of a forming object, adhesive strength rises and it can control exfoliation. Furthermore, as described in the first modification, since the vibrational stress is dispersed at the interface between the cover and the adhesive surface, the stress is more relaxed. Of course, one or more rib portions may be provided on the inner surface side of the cover.

  The width of the U-shaped cover may be wider than the width of the terminal portions 2a and 2b and equal to or less than the width of the molded body 1, but is preferably equal to the width of the molded body. Since the cover opening (bottom surface) faces upward when curing the adhesive, it is possible that the U-shaped or the like may easily run off when the adhesive is applied or filled and cured. This problem can be solved by providing an inner surface rib in the vicinity of the end face separately from the rib portion.

  The second modification may be applied to the cover in the second and third embodiments described later.

  As described above, according to the first embodiment, the first and second modifications of the present invention, it is possible to cope with a high density surface mounting process while ensuring the reliability required as an on-vehicle component. It is possible to provide a coil component that can be

Second Embodiment
A second embodiment of a coil component according to the invention will be described with reference to FIGS. 3 and 4. FIG. 3 is a perspective view of a second embodiment of a coil component according to the invention, and FIG. 4 is a longitudinal cross-sectional view of the coil component of FIG. 3 along the line C-C '. In FIG. 3 and FIG. 4, the same components as those shown in FIG. 1 and FIG. 2 are given the same reference numerals, and detailed description may be omitted.

  In FIGS. 3 and 4, the difference between a coil component 200 according to the second embodiment and the coil component 100 according to the first embodiment is as follows. On the outside of the cover 3, a fixing bracket 5 is provided which extends over the top surface of the cover 3 and the bottom surface of the molded body 1. The fixing bracket 5 is formed by bending a flat plate made of spring steel or the like. The fixing bracket 5 is formed and disposed in contact with the outer surface of the cover 3. That is, the fixing bracket 5 has a gate-like shape extending along the outer surface of the cover 3 toward the end surface (bottom surface) side, and further includes a terminal 5b bent along the bottom surface of the molded body 1 There is. Surface treatment such as Sn plating may be performed on the surfaces of the fixing bracket 5 and the terminal portion 5b. In addition, it is preferable that the fixing bracket 5 be bent into an M shape in which the center of the upper surface portion is slightly recessed from both sides. By so doing, it becomes easy to bring the fixing bracket 5 into contact with the side surface and the upper surface of the cover 3 and it becomes possible to fix the fixing bracket 5 more firmly. The width of the fixing bracket 5 other than the terminal portion 5 b may be wider than the terminal portion 5 b so as not to exceed the side surface of the molded body 1.

  Moreover, it is preferable to have the notch part 3b in the end surface part (bottom face part) of the cover 3 which adjoins to the terminal part 5b. By doing this, the bending radius of the bending process for forming the terminal portion 5 b in the fixing bracket 5 can be increased, and the process becomes easy. Furthermore, it is desirable to form the recessed part 1b for accommodating and arrange | positioning the front-end | tip part of the terminal part 5b in the bottom face of the molded object 1. As shown in FIG. In addition, the surface of the terminal portion 5b of the fixing bracket 5 opposed to the mounting surface and the surface of the terminal portions 2a and 2b (terminal bottom portion) connected to the coil 2 opposed to the mounting surface are on the same plane. Preferably, it is configured to be located. By doing this, when mounting by solder on the land of the mounting substrate using a reflow soldering tank, in addition to the terminal bottom portions of the terminal portions 2a and 2b connected to the coil 2, the terminal portion 5b of the fixing bracket 5 is also Solder mounting can be performed, and fixation to a mounting substrate can be performed more firmly.

  In addition, when mounting a fixing bracket with an adhesive instead of solder mounting, it may replace with a fixing bracket and may use the fixing member made of resin, for example.

(Effect of the second embodiment)
The coil component 200 according to the second embodiment has the same configuration as that of the coil component 100 according to the first embodiment, and further includes a fixing bracket 5 straddling the upper surface of the cover and the bottom surface of the molded body outside the cover 3 . Therefore, the coil component 200 exerts the following effects in addition to the same effects as the effects described in the first embodiment.

  The coil component 200 is generally mounted on the land of the mounting substrate by solder using a reflow soldering bath, but at this time the terminal portion 5b of the fixing bracket 5 is also fixed on the land of the mounting substrate by solder. The fixing strength can be improved as compared with only the solder mounting in the terminal portions 2a and 2b, and peeling due to stress caused by the vibration applied to the solder surface can also be suppressed. Further, the presence of the fixing bracket 5 can also prevent the cover 3 from falling off by any chance.

Third Embodiment
A third embodiment of a coil component according to the present invention will be described with reference to FIGS. FIG. 5 is a perspective view of a third embodiment of a coil component according to the present invention, and FIG. 6 is a longitudinal cross-sectional view of the coil component of FIG. 5 taken along the line D-D '. In FIGS. 5 and 6, the same components as those shown in FIGS. 1 to 4 are denoted by the same reference numerals, and detailed description may be omitted.

  In FIGS. 5 and 6, the difference between the coil component 300 according to the third embodiment and the coil component 200 according to the second embodiment is as follows. The fixing bracket 5 has an annular portion 6 having a through hole at a portion in contact with the upper surface of the cover 3 on the upper surface thereof. The action of the annular portion 6 is as follows. When the coil 2 is energized, a magnetic flux is generated in the molded body 1, and a part of the magnetic flux may be a leakage magnetic flux leaking from the upper surface of the molded body 1 to the surrounding space. In this case, when the leakage magnetic flux interlinks with the surrounding electronic parts and the substrate wiring, noise is generated, which is a factor that hinders the miniaturization of the electronic control device. On the other hand, the leakage flux from the upper surface of the molded body 1 is around the through hole 6 by forming a through hole as a portion in contact with the upper surface of the cover 3 on the upper surface of the fixing bracket 5 as the annular portion 6. It is shielded by the eddy current generated in As a result, according to the third embodiment, in addition to the effect that the fixation with the mounting substrate can be performed more firmly as described in the second embodiment, the effect of suppressing the generation of noise can be obtained. It becomes possible to provide a coil component more suitable for downsizing of the electronic control device.

  In the third embodiment, in order to improve the noise suppression effect, iron, aluminum, copper or the like may be used as the material of the fixture 5 instead of spring steel.

(Effect of the third embodiment)
The coil component 300 according to the third embodiment has the same configuration as that of the coil component 100 according to the first embodiment, and further includes a fixing fitting 5 straddling the upper surface of the cover and the bottom surface of the molded body outside the cover 3 . Moreover, the fixing bracket 5 is configured to have a through hole as an annular portion 6 in a portion in contact with the upper surface of the cover 3 on the upper surface thereof. Therefore, the coil component 300 exerts the following effects in addition to the same effects as the effects described in the first embodiment.

  The coil component 300 is generally mounted on the land of the mounting substrate by solder using a reflow soldering bath, but at this time the terminal portion 5b of the fixing bracket 5 is also fixed on the land of the mounting substrate by solder. The fixing strength can be improved as compared with only the solder mounting in the terminal portions 2a and 2b, and peeling due to stress caused by the vibration applied to the solder surface can also be suppressed. Further, the presence of the fixing bracket 5 can also prevent the cover 3 from falling off by any chance. Furthermore, when the portion facing the cover upper surface portion of the fixing bracket 5 is formed as the annular portion 6, noise generation due to leakage flux from the molded body 1 can be suppressed by eddy current, and coil parts suitable for miniaturization of electronic control devices Play an effect.

  Next, Examples 1 to 3 corresponding to the first to third embodiments will be described.

Example 1
A flat wire with a width of 1.0 mm and a thickness of 0.45 mm covered with an insulating film of polyamide imide was rolled at the end of the coil 2 wound by 5.5 turns with an inner diameter of 3.0 mm to a thickness of 0.15 mm Thereafter, it was molded to have a width of 2.0 mm, and this portion was plated with solder. Iron-based magnetic powder (Fe-Si-Cr) with an average particle size of 10 to 20 μm and a binder containing an epoxy-based thermosetting resin are mixed in a non-heated state in which the thermosetting resin is not completely cured The powder which becomes a compact was obtained. The coil 2 and a part of the terminal portions 2a and 2b were embedded with the powder to be this molded body, and pressure molding was performed at 3.0 to 10.0 t / cm ² to obtain a molded body 1 of 7 mm × 7 mm × 5 mm in height . After the molded body 1 is dried at 150 ° C., a portion to be a terminal portion is drawn along the side of the molded body 1 and further bent along the bottom of the molded body 1 to form a terminal portion 2a. , 2b. On the other hand, the liquid crystal polymer was injection-molded to prepare a cover 3 having a thickness of 0.3 mm and an inner thickness of 8.5 mm × 8.5 mm × height 5.7 mm. On the inner surface of the cover 3, a plurality of rib portions 3a having a height of 0.7 mm and a width of 0.5 mm are provided on the inner side surface portion and a part of the top surface portion. Apply 30 vol% of epoxy resin and glass filler to the inner surface of the cover 3 to the extent that the tip of the rib 3a is not applied, thinly apply the epoxy resin to the surface of the molded body 1, and combine them The heat curing was performed at 100 ° C. for 2 hours to form the bonding member 4, and the coil component 100 was obtained.

  The coil component 100 achieves the effects as described in the first embodiment.

Example 2
In the same manner as in Example 1, the molded body 1 and the terminal portions 2a and 2b of the coil were formed. On the other hand, the liquid crystal polymer was injection-molded to prepare a cover 3 having a thickness of 0.3 mm and an inner thickness of 8.5 mm × 8.5 mm × height 5.7 mm. At this time, notches 3b each having a width of 4.1 mm and a height of 0.6 mm were provided in a pair of opposing end surface portions (bottom surface portions) of the cover 3. On the inner surface of the cover 3, a plurality of rib portions 3a having a height of 0.7 mm and a width of 0.5 mm are provided on the inner side surface portion and a part of the top surface portion. Apply 30 vol% of epoxy resin and glass filler to the inner surface of the cover 3 to the extent that it does not touch the tip of the rib 3a and thinly apply the epoxy resin to the surface of the molded body 1, then cut out These were combined in such a direction that the surface on which 3b was provided and the surface on which the terminal portions 2a and 2b of the coil were not opposed, and heat curing was performed at 100 ° C. for 2 hours to form an adhesive member 4. Furthermore, after preparing spring steel of 2.0 mm in width and 0.15 mm in thickness and performing Sn plating treatment, it performs M-shaped bending so that the inside thickness becomes 9 mm in width and 9.8 mm in height, and further to the tip portion Bending was applied to form a fixture 5 having a terminal portion 5b. The coil component 200 was obtained by combining the above from the upper surface side of the cover 3.

  The coil component 200 achieves the effects as described in the second embodiment.

Example 3
In the same manner as in Example 2, the molded body 1, the terminal portions 2a and 2b of the coil, the cover 3 and the bonding member 4 were formed. A spring steel having a thickness of 0.15 mm was stamped out to prepare a fixture 5 having an annular portion 6 having a through hole with a diameter of 3 mm. The plate material of the fixing bracket 5 had a width of 5.2 mm around the annular portion 6 and a width of 2 mm at the other portions. After applying Sn plating to this, M-shaped bending is performed so that the inner thickness is 9 mm wide and 9.8 mm high, and bending is further applied to the tip portions of the two leg portions to make the terminal portion 5 b The fixing bracket 5 was formed. The coil component 300 was obtained by combining the above from the upper surface side of the cover 3.

  The coil component 300 achieves the effects as described in the third embodiment.

  As described above, the first to third embodiments and the first and second modifications of the present invention have been described, but as described in the description of the first embodiment, the first to third embodiments of the present invention are described. The present invention is not limited to the configuration of the embodiment, and changes and modifications of the configuration can be made without departing from the scope of the present invention. That is, various modifications and alterations that can be made by those skilled in the art are also included in the present invention.

  For example, although Fe-Si-Cr has been exemplified as the magnetic powder, the present invention is not limited to this, and another Fe alloy, a nickel alloy, a cobalt alloy or the like may be used. Further, although an epoxy resin is exemplified as the bonding member, an adhesive such as an acrylic resin may be used as long as the bonding strength between the molded body and the terminal portion and the cover can be maintained and the durability is excellent. . Furthermore, the curing conditions of the adhesive member are not limited to those illustrated, and the adhesive member to be used may have room temperature curability.

  The coil component of the present invention can achieve high reliability such as impact resistance and can maintain good heat dissipation, and is useful for various electronic devices, particularly for in-vehicle electronic devices.

DESCRIPTION OF SYMBOLS 1 Molded object 1a, 1b Recess 2 Coil 2a, 2b Terminal part 3 Cover 3a Rib part 3b Notch part 4 Bonding member 5 Fixing bracket 5b Terminal part 6 Annular part

Claims (11)

A compact containing magnetic powder and a binder;
A coil made of a conductor,
It has a cover made of insulator,
The molded body includes at least a bottom surface serving as a mounting surface, a top surface opposite to the bottom surface, and a side surface contacting one side of an edge of the bottom surface.
The coil is embedded in the molded body, and includes a terminal portion that protrudes from the side surface, faces the bottom surface side, and is bent along the bottom surface.
The cover covers the terminal portion and the vicinity thereof on the side surface of the molded body, and a part of the side surface of the molded body.
An adhesive is disposed in the gap between the side surface of the molded body and the terminal portion, the gap between the terminal portion and the cover, and the gap between the side surface of the molded body and the cover Coil parts characterized by   The coil component according to claim 1, wherein the cover further covers at least a part of the upper surface of the molded body.   The coil component according to claim 2, wherein the cover has a U-shaped shape that is bent from the top surface to the side surface of the molded body and extends to the bottom surface side.   The coil component according to claim 3, wherein the width of the cover in the U-shaped shape is equal to or greater than the width of the terminal portion on the side surface of the molded body and equal to or smaller than the width of the molded body.   The coil component according to claim 1, wherein the cover is in a box shape covering the upper surface and the side surface of the molded body.   A U-shaped fixing member extending toward the bottom side of the molded body along the outer surface of the cover, further comprising a fixing member having a terminal portion along the bottom surface of the molded body The coil component according to any one of claims 1 to 5, wherein   The coil component according to claim 6, characterized in that the width of the fixing member is wider than the terminal portion of the fixing member and does not exceed the side surface of the molded body.   The coil component according to claim 6 or 7, wherein the fixing member is a metal fixing fitting and has an annular portion having a through hole at a portion in contact with the upper surface of the cover.   9. The coil component according to claim 8, wherein the terminal portion of the coil and the terminal portion of the fixing bracket are used as soldered portions of the mounting surface.   The coil component according to any one of claims 1 to 9, wherein a plurality of rib portions are provided on the inner surface of the cover facing the molded body.   An on-vehicle electronic device comprising the coil component according to any one of claims 1 to 10.

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