JP2012174815A - Coil component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly reliable coil component which prevents cracks and chips in a compact due to vibration and impact and noise caused by contact between the compact mounted on a substrate and terminal parts.SOLUTION: Coils 11 formed of a conductive material is buried in a compact 10 formed of a magnetic material, and terminal parts 12, each of which protrudes from the compact 10, are respectively bent along areas from side surfaces to a bottom surface of the compact 10. At least a part of a gap, formed by the compact 10 and the terminal part 12 that are arranged so as to face each other, is fixed by an adhesive member 13.

Description

  The present invention relates to a coil component for use in electronic equipment, communication equipment, and the like.

  As a configuration of a conventional coil component, there is a configuration in which a coil made of a conductive material is embedded in a molded body made of a magnetic material, and a terminal portion protruding from the side surface of the molded body is bent from the side surface toward the bottom surface. In the coil component having this configuration, since the terminal portion is bent from the side surface to the bottom surface of the molded body, the molded body near the protruding position where the terminal portion protrudes from the molded body is subjected to stress. Therefore, if vibration or impact is applied to the substrate in a state where it is mounted on the substrate, there is a possibility that the molded body near the protruding position where the terminal portion protrudes from the molded body may be cracked or chipped. If the magnetic powder and the fragments of the molded body that accompany the cracks and chips are scattered on the substrate, there is a risk of problems such as short circuits and poor contact, and a decrease in reliability.

  Therefore, for example, Patent Document 1 discloses a method for relaxing the stress applied to the molded body in the vicinity of the protruding position where the terminal portion protrudes from the molded body, and suppressing the occurrence of cracks and chipping of the molded body due to vibration and impact. There is a way. The conventional coil component disclosed in Patent Document 1 includes a molded body in which a magnetic material is powdered, the surface is covered with an insulating film, a binder is mixed, and pressure-molded, and the molded body is embedded in the molded body and from the molded body. The coil which made the edge part protrude and the holding member which hold | maintains the edge part of this coil are provided. The end of the coil is overlapped with the holding member and bent from the side of the molded body to the bottom, and a recess is provided on the side of the molded body from the protruding position of the end of the coil toward the top of the molded body. It has a configuration. With this configuration, it is intended to suppress the occurrence of cracks and chips in the molded body by relaxing the stress due to vibration and impact applied to the molded body at the protruding position where the end of the coil projects.

JP 2006-324457 A

  However, in the method disclosed in Patent Document 1, since only the stress on the upper surface side from the protruding position where the terminal portion protrudes from the molded body is relieved, the stress on the lower surface side, the left surface side, and the right surface side is relieved from the protruding position. It has not been. In addition, since stress is applied only to the molded body in the vicinity of the protruding position where the terminal portion protrudes from the molded body, it is difficult to prevent cracking or chipping of the molded body caused by vibration or impact, which may reduce reliability. There are challenges. Further, there is a problem that noise may be generated when the molded body and the terminal portion come into contact with each other due to externally applied vibration after the substrate is mounted.

  In view of the above, an object of the present invention is to provide a coil component that is excellent in reliability by preventing cracking and chipping of a molded body due to vibration and impact and noise caused by contact between the molded body after mounting on a substrate and a terminal portion.

  In order to solve the above problems, a coil component according to the present invention includes a molded body obtained by mixing a magnetic powder and a binder and press-molding, and a coil embedded in the molded body. Is provided with at least a bottom surface serving as a mounting surface and a side surface in contact with an edge of the bottom surface, and the coil includes a terminal portion protruding from the side surface of the molded body and bending toward the bottom surface, At least a part of the gap with the terminal portion is fixed by an adhesive member.

  The coil component according to the present invention is characterized in that the terminal portion is an end portion of the coil.

  In the coil component according to the present invention, the end portion of the coil and the joint portion of the terminal portion are connected, and a part of the terminal portion including the whole coil and the joint portion of the terminal portion is embedded in the molded body. It is characterized by being.

  Although there is no particular limitation as long as the molded body and the terminal portion are fixed by the adhesive member, at least a part of the gap between the side surface of the molded body and the terminal portion facing the side surface is fixed by the adhesive member. It is desirable that With this structure, the stress on the upper surface side, the lower surface side, the left surface side, and the right surface side caused by vibration and impact is dispersed on the adhesive surface where the molded body and the terminal portion are fixed by the adhesive member, It becomes possible to relieve the stress applied to the molded body in the vicinity of the protruding position where the terminal portion protrudes from the molded body. Furthermore, since the adhesive member serves as a buffer material between the molded body and the terminal portion, it is possible to prevent noise generated by vibration after mounting on the substrate.

  The coil component according to the present invention is characterized in that the width of at least a part of the surface of the terminal portion fixed by the adhesive member is wider than the width of the protruding terminal portion.

  By increasing the bonding area where the molded body and the terminal portion are fixed by the adhesive member, it is possible to increase the adhesive force between the molded body and the terminal portion. Further, since the bonding area is widened, stress generated by vibration or impact can be further dispersed, and stress applied to the molded body in the vicinity of the protruding position where the terminal portion projects from the molded body can be further relaxed. It becomes possible.

  The coil component according to the present invention is characterized in that at least a part of the surface of the terminal portion fixed by the adhesive member has irregularities.

  By providing unevenness on at least a part of the bonding surface of the terminal portion fixed by the molded body and the adhesive member, the molded body and the terminal portion can be formed without increasing the width of the terminal portion and increasing the bonding area. It becomes possible to strengthen the adhesive strength.

  The coil component according to the present invention is characterized in that a portion of the terminal portion that is opposed to the side surface of the molded body and fixed by the adhesive member has a through hole.

  By providing a through hole in a portion of the terminal portion that is fixed to the side surface of the molded body that is fixed by the adhesive member, the terminal portion is bent from the side surface of the molded body along the bottom surface. When the adhesive member is applied, the adhesive member can be applied from the through hole, and the adhesive member can be easily applied.

  According to the present invention, since the molded body and the terminal portion are fixed by the adhesive member, stress due to vibration or impact is dispersed on the adhesive surface, and the stress applied to the molded body near the protruding position where the terminal portion protrudes from the molded body. Can be mitigated, and cracking and chipping of the molded product can be prevented. Further, since the adhesive member serves as a buffer material between the molded body and the terminal portion, it is possible to prevent noise caused by the contact between the molded body and the terminal portion caused by vibration after mounting on the substrate.

  As described above, it is possible to prevent a crack or chip of the molded body due to vibration or impact and noise due to contact between the molded body after mounting on the substrate and the terminal portion, and to obtain a coil component having excellent reliability.

It is a top view which shows the state before bending the terminal of the coil components by this invention. It is sectional drawing of the coil components by this invention. It is a perspective view which shows an example of the coil components by this invention. It is a perspective view which shows the other example of the coil components by this invention. It is a perspective view which shows another example of the coil components by this invention.

  Hereinafter, embodiments of the present invention will be described in detail.

  FIG. 1 is a plan view showing a state before bending a terminal of a coil component according to the present invention. FIG. 2 is a cross-sectional view of a coil component according to the present invention. FIG. 3 is a perspective view showing an example of a coil component according to the present invention. FIG. 4 is a perspective view showing another example of the coil component according to the present invention. FIG. 5 is a perspective view showing another example of the coil component according to the present invention.

  As shown in FIGS. 1-5, the coil component by this invention connects the edge part of the coil 11 which consists of electrically conductive materials, and the junction part of the terminal parts 12, 22, 32, 42, and the whole coil 11 and terminal part are connected. Part of the terminal portions 12, 22, 32, and 42 including the joint portions 12, 22, 32, and 42 are embedded in the molded body 10. Further, the terminal portions 12, 22, 32, and 42 protruding from the side surface of the molded body 10 are bent from the side surface to the bottom surface of the molded body 10. Further, the adhesive member 13 is applied to at least a part of a gap formed by bending the terminal portions 12, 22, 32, 42 and the terminal portions 12, 22, 32, 42. The terminal portions 12, 22, 32, 42 are fixed by the adhesive member 13. Here, although the structure which connects the edge part of the coil 11 and the junction part of terminal part 12,22,32,42 is shown, even if the terminal part 12,22,32,42 is an edge part of the coil 11, it shows. Good.

  Further, as shown in FIG. 3, the terminal portion 22 may have a width of a surface to which the adhesive member 13 is applied wider than a width of the terminal portion 22 protruding from the molded body 10. The bonding surface of the terminal portion 22 including the bonding surface wider than the width of the terminal portion 22 protruding from the molded body 10 and the molded body 10 are fixed by the adhesive member 13. Since the width of a part of the bonding surface for fixing the terminal portion 22 with the molded body 10 and the adhesive member 13 is wider than the width of the terminal portion 22 protruding from the molded body 10, the molded body 10 and the terminal portion 22 are bonded to each other. 13 can increase the bonding area to be bonded.

  By increasing the adhesion area, it is possible to further disperse the stress due to vibration and impact applied to the molded body 10 in the vicinity of the protruding position of the terminal portion 22 protruding from the molded body 10. By dispersing the stress over a wide area, the stress applied to the molded body 10 in the vicinity of the protruding position of the terminal portion 22 protruding from the molded body 10 is reduced. Thereby, the crack of the molded object 10 of the protrusion position vicinity of the terminal part 22 and a chip | tip can be prevented stably.

  Moreover, as shown in FIG. 4, the one part adhesive surface of the terminal part 32 fixed with the molded object 10 and the adhesive member 13 may have an unevenness | corrugation. The bonding surface of the terminal portion 32 including the uneven surface and the molded body 10 are fixed by the bonding member 13. By providing unevenness on a part of the bonding surface for fixing the terminal portion 32 with the molded body 10 and the adhesive member 13, the width of the terminal portion 32 is widened and the bonding area is not increased, so that the molded body 10 and the terminal portion 32 can be expanded. The adhesion area is increased and a strong adhesion can be obtained.

  By strengthening the adhesive force, it is possible to prevent the molded body 10 and the terminal portion 32 from being detached due to vibration or impact. By preventing the bonding between the molded body 10 and the terminal portion 32, the stress due to vibration or impact applied to the molded body 10 in the vicinity of the protruding position of the terminal portion 32 protruding from the molded body 10 is reduced. It becomes possible to stably disperse 32 on the adhesive surface fixed by the adhesive member 13.

  In addition, the terminal portion 32 is provided with irregularities on a part of the bonding surface for fixing the terminal portion 32 with the molded body 10 and the adhesive member 13, and further, a part of the surface to which the adhesive member 13 is applied protrudes from the molded body 10. It can also be made wider than the width. A part of the bonding surface for fixing the terminal part 32 with the molded body 10 and the adhesive member 13 has irregularities, and further, by expanding the width of a part of the bonding surface of the terminal part 32 to widen the bonding area, the molded body 10 It is possible to strengthen the adhesive force of the terminal portion 32 and reduce the stress applied to the molded body 10 in the vicinity of the protruding position of the terminal portion 32 protruding from the molded body 10.

  The application of the adhesive member 13 to the gap between the molded body 10 and the terminal portion 32 is not particularly limited as long as it is applied to such an extent that the molded body 10 and the terminal portion 32 are fixed. desirable. By applying so as to fill the gaps between the concaves and convexes, the bonding area is widened and the bonding force can be increased.

  As shown in FIG. 5, the side surface of the molded body 10 and the bonding surface of the terminal portion 42 fixed by the bonding member 13 may have a through hole. The bonding surface of the terminal portion 42 including the surface having the through hole and the molded body 10 are fixed by the bonding member 13. When the adhesive member 13 is applied after being bent along the bottom surface from the side surface of the molded body 10 by having a through hole in the adhesive surface for fixing the terminal portion 42 with the molded body 10 and the adhesive member 13, the adhesive member 13 can be applied to the gap between the molded body 10 and the terminal portion 42 through the through-hole, and the adhesive member 13 can be easily applied.

  Further, at least a part of the adhesion portion of the terminal portion 42 having the through hole may be wider than the width of the terminal portion 42 protruding from the molded body 10. When the adhesive member 13 is applied after the terminal portion 42 is bent by providing a through hole in the terminal portion 42 having a larger bonding area, the adhesive member is applied to the gap between the molded body 10 and the terminal portion 42 from the through hole. Thus, it can be reliably applied to the inside of the terminal portion which has become wider than that applied from the gap between the molded body 10 and the terminal portion 42. Further, by increasing the width of a part of the terminal portion 42, the strength of the portion provided with the through hole is also reinforced.

  Further, even if at least a part of the adhesion part of the terminal part 42 having the through hole has irregularities, or at least a part of the adhesion part of the terminal part 42 protrudes from the molded body 10. It may be wider than the width. By providing through holes in these terminal portions 42, when the adhesive member 13 is applied after the terminal portions 42 are bent, the adhesive member 13 can be applied to the gap between the molded body 10 and the terminal portion 42 through the through holes. It is possible for the adhesive member 13 applied from the hole to reach the whole through the concave and convex grooves, and can be applied so as to fill the concave and convex gaps. When a liquid adhesive is used as the adhesive member 13, a liquid reservoir for the adhesive member 13 is provided by increasing the gap between the molded body 10 and the terminal portion 42 in the vicinity of the through hole. In addition, the adhesive member 13 can be permeated over a wide range of the gap between the molded body 10 and the terminal portion 42.

  The adhesive member 13 is not particularly limited as long as it fixes the molded body 10 and the terminal portions 12, 22, 32, and 42. However, the adhesive member 13 hangs on the bottom surface of the terminal portions 12, 22, 32, and 42, which are mounting locations. It is desirable to use the adhesive member 13 that has thixotropy as much as possible and that has a small resin flow. Further, the adhesive member 13 applied from the through hole has a thixotropy that prevents resin flow to the bottom surface of the terminal portion 42 and can be applied to the gap between the molded body 10 and the terminal portion 42 through the through hole. It is desirable.

  Examples of the present invention will be specifically described.

Example 1
The present embodiment has a configuration as shown in FIG. An end of a coil obtained by winding a 0.5φ round wire covered with a polyamide-imide insulating film for 6.5 turns with an inner diameter of 2.0 mm and a joint of a terminal portion having a width of 3.2 mm were connected. Further, a part of the terminal portion had a width of 5.0 mm. An iron-based magnetic powder (Fe—Si—Cr) having an average particle size of 10 to 20 μm and a binder containing an epoxy-based thermosetting resin are mixed in an unheated state where the thermosetting resin is not completely cured. Thus, a powder to be a molded body was obtained. A part of the terminal part including the joint part of the coil and the terminal part is embedded with the powder to be the molded body, and pressure molding is performed at 3.0 to 10.0 t / cm ² to obtain 7 mm × 7 mm × 3 mm height. A molded body was obtained.

  After drying this molded body under the condition of 150 ° C., when the terminal portion is bent along the side surface of the molded body, the portion facing the side surface of the molded body is a portion where the width of the terminal portion is wide. An epoxy resin adhesive with high thixotropy and low resin flow was applied. After coating, the terminal part was bent along the bottom surface from the side of the molded body, and the terminal part coated with the adhesive was pressed from both sides for 5 minutes to obtain a coil component in which the molded body and the terminal part were fixed. .

(Example 2)
The present embodiment has a configuration as shown in FIG. It has a hole penetrating through a part of the surface to which the adhesive is applied, and an end portion of a coil obtained by winding a 0.5φ round wire covered with a polyamide-imide insulating film for 6.5 turns with an inner diameter of 2.0 mm. The junction part of the terminal part whose width is 3.2 mm was connected. 1. An iron-based magnetic powder (Fe—Si—Cr) having an average particle size of 10 to 20 μm and a binder containing an epoxy-based thermosetting resin are mixed in an unheated state where the thermosetting resin is not completely cured. A plurality of green compacts pressure-molded at 0 to 4.0 t / cm ² were obtained. A part of the terminal part including the joined part of the coil and the terminal part was sandwiched with the green compact, and re-press molding was performed to obtain a molded body of 7 mm × 7 mm × height 3 mm.

  After the molded body was dried at 150 ° C., the terminal portion was bent along the bottom surface from the side surface of the molded body. An epoxy resin adhesive was applied to the gap between the terminal portion and the side surface of the molded body through the through hole of the terminal portion. After the application, the terminal part to which the adhesive was applied was pressed and cured at 150 ° C. for 60 minutes to obtain a coil component in which the molded body and the terminal part were fixed.

  As described above, the coil component of the present invention bonds stress generated by vibration or impact by fixing at least a part of the molded body and the terminal portion bent along the bottom surface from the side surface of the molded body. It becomes possible to disperse on the surface. This prevents stress due to vibration or impact from concentrating only on the molded body in the vicinity of the protruding position where the terminal portion projects from the molded body. Therefore, the stress applied to the molded body in the vicinity of the protruding position of the terminal portion is reduced, and it is possible to prevent cracks and chips from occurring. In addition, the adhesive member in the gap between the molded body and the terminal portion serves as a cushioning material, and it is possible to prevent the occurrence of noise due to contact between the molded body and the terminal portion due to vibration after mounting on the substrate. At the same time, it is possible to prevent the spring-back of the bent terminal and to prevent the coil component from floating from the circuit board.

  As mentioned above, although the Example of this invention was described, this invention is not limited to said embodiment and Example, The change of a structure, correction, material, etc. in the range which does not deviate from the summary of this invention. Can be changed. For example, although Fe—Si—Cr is exemplified as the magnetic powder, the present invention is not limited to this, and other Fe alloys, nickel alloys, cobalt alloys, and the like may be used. In addition, the epoxy resin is exemplified as the adhesive member, but it is sufficient that the adhesive strength between the molded body and the terminal portion can be maintained and the durability is excellent. Also good. Furthermore, the curing conditions of the adhesive member are not limited to those illustrated, but if the adhesive member to be used has thermosetting properties, temperature and time conditions are required and can be changed depending on the characteristics of the adhesive member to be used. is there.

DESCRIPTION OF SYMBOLS 10 Molded body 11 Coil 12, 22, 32, 42 Terminal part 13 Adhesive member

Claims (6)

  A molded body formed by mixing magnetic powder and a binder and press-molding, and a coil embedded in the molded body, the molded body having a bottom surface serving as a mounting surface and an edge on an edge of the bottom surface At least a side surface in contact with the coil, and the coil includes a terminal portion that protrudes from the side surface of the molded body and bends toward the bottom surface, and at least a part of a gap between the side surface and the terminal portion is fixed by an adhesive member. Coil parts characterized by that.   The coil component according to claim 1, wherein the terminal portion is an end portion of the coil.   The end part of the coil and a joint part of the terminal part are connected, and a part of the terminal part including the joint part of the whole coil and the terminal part is embedded in the molded body. The coil component according to 1.   4. The coil component according to claim 1, wherein a width of at least a part of a surface of the terminal portion fixed by the adhesive member is wider than a width of the protruding terminal portion.   5. The coil component according to claim 1, wherein at least a part of a surface of the terminal portion fixed by the adhesive member has irregularities.   6. The coil component according to claim 1, wherein a portion fixed by the adhesive member of the terminal portion facing the side surface of the molded body has a through hole.

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