JP4727325B2 - Surface mount type coil - Google Patents

Description

  The present invention relates to a surface mount coil used for various electronic devices and the like.

  Conventionally, various surface mount coils used for electronic devices and the like have been proposed. These surface mount type coils are provided with a drum type core having an upper collar part and a lower collar part at both ends of a winding shaft part around which a winding is wound. A metal terminal is attached to the outer peripheral surface of the mold core (see, for example, Patent Document 1, Patent Document 2, and Patent Document 3).

JP 2001-338817 A JP 2001-338818 A JP 2003-109823 A

  By the way, when a current flows through such a surface mount coil, the windings generate heat. In particular, when the drum core is housed in the ring core, there is no gap at the top of the ring core, and the heat generated by the winding is trapped inside the ring core.

  For this reason, a change may occur in the electrical characteristics, and the performance as designed may not be sufficiently exhibited, or the core member and the like may be rapidly deteriorated by repeated heating and cooling.

  The present invention has been proposed in view of the above-described circumstances, and by providing a heat dissipation effect, it is possible to reliably exhibit the performance as designed, and to provide a surface mount coil with excellent durability. Objective.

In order to achieve the above-described object, the surface mount coil of the present invention has a drum core having an upper collar part and a lower collar part at both ends of a winding shaft part for winding a winding,
A ring-type core that houses the drum-type core;
A surface mount type coil comprising two metal terminals mounted at positions facing each other on the outer peripheral surface of the ring core;
The upper collar of the drum core is placed on the upper end of the ring core;
A space portion having a circular cross section is provided from the upper surface to the lower surface at least at two locations in the diametrical direction at the inner peripheral portion of the ring core, and the upper collar portion of the drum core is the ring shape. When placed on the upper end of the core, the winding is configured to be drawn from the space,
Each metal terminal includes a band-shaped portion covering one outer side surface of the ring core and two corners adjacent to the one outer side surface, and a bend arranged so as to sandwich these corner portions from above and below. Part
Of the bent portions of each of the metal terminals, the upper portion of the bent portion corresponding to at least one corner, and electrically connected to the end of the winding at a position corresponding to the space portion For this purpose, a cut groove into which a part of the end of the winding is fitted is formed,
By bringing the inner end of the upper part of each of the bent portions into contact with the outer peripheral portion of the upper collar portion of the drum core, the outer peripheral portion of the lower collar portion of the drum core and the ring mold It is configured to be able to ensure a predetermined width interval between the inner peripheral portion of the core and the core .

  Here, it is preferable that the metal terminals are attached in close contact with the outer surface and the corner of the ring core.

Furthermore, it is preferable that a kerf is provided in the upper part of all the bent portions of all the metal terminals that are in contact with the outer peripheral portion of the upper collar portion of the drum core .

Moreover, it is preferable that the lower part of the bending part of all the said metal terminals is a substantially hexagonal mounting part .

  In the invention described in Patent Document 1, Patent Document 2, and Patent Document 3, a metal terminal is mounted on the outer peripheral surface of the ring-type core. The metal terminal includes a drum-type core and a ring-type core. This prevents the core from falling off the mounting board, leaving the vicinity of the metal terminal mounting portion. That is, the inventions described in the above patent documents are intended to improve impact reliability, and are not intended to enhance the heat dissipation effect as in the present invention. The literature does not provide any suggestion for the purpose, structure and effect of the present invention.

  According to the surface mount type coil of the present invention, since the two metal terminals are mounted on the outer peripheral surface of the ring type core so as to face each other, the heat generated in the windings passes through each metal through the ring type core. Conducted to the terminal and dissipated into the outside air. Therefore, the heat dissipation effect is enhanced, the performance as designed can be surely exhibited, and the durability can be improved.

  Further, by attaching each metal terminal in close contact with the outer surface and corners of the ring core, the thermal conductivity between the ring core and the metal terminal is increased, and the heat dissipation effect can be further enhanced.

  Further, by interposing a heat conductive member between each metal terminal and the outer surface and corner of the ring core, the thermal conductivity between the ring core and the metal terminal is further increased, and further The heat dissipation effect can be enhanced.

Hereinafter, embodiments of the surface mount coil of the present invention will be described with reference to the drawings.
1 to 4 show a surface mount coil according to a first embodiment of the present invention. FIG. 1 is an exploded perspective view of the surface mount coil. FIG. 2 is a longitudinal sectional view of the surface mount coil. 3 is a perspective view of a state in which the ring-type core to which the metal terminal is attached is viewed from above, and FIG. 4 is a perspective view of the state in which the ring-type core to which the metal terminal is attached is viewed from below.

  As shown in FIGS. 1 to 4, the surface mount coil 10 according to the first embodiment of the present invention has an upper flange portion 23 and a lower flange portion 24 at both ends of a winding shaft portion 22 around which a winding 21 is wound. And a ring core 30 that accommodates the drum core 20 therein, and two metal terminals 40 are mounted on the outer peripheral surface of the ring core 30 at positions facing each other. Has been.

  As shown in FIG. 1, the drum-type core 20 is formed so that the outer diameter of the upper collar part 23 is larger than the outer diameter of the lower collar part 24. In the present embodiment, the outer diameter of the upper collar portion 23 is formed to be larger than the inner diameter of the ring core 30, and the drum core 30 is accommodated in the ring core 30 while the drum core 20 is housed in the ring core 30. The upper collar portion 23 of the drum core 20 is placed on the upper end portion. Further, as shown in FIG. 2, the lower flange portion 24 of the drum core 20 is formed at a position such that the lower surface thereof is slightly above the lower surface of the ring core 30.

  Moreover, as shown in FIG. 1, the groove part 25 is formed in the outer peripheral part of the upper collar part 23 of the drum-type core 20 in two places which oppose a diameter direction. This groove part 25 is for drawing out each end part 21a, 21b of the coil | winding 21 wound by the winding shaft part 22 outside.

  As shown in FIG. 1, the ring-shaped core 30 has a substantially rectangular outer shape, and each corner is notched to form a notch surface 31, and the notch surfaces 31 located diagonally are substantially parallel to each other. Has been. Further, a fitting recess 32 into which the mounting portion of the metal terminal 40 is fitted is formed on the lower surface near each corner of the ring core 30.

  Further, in the inner peripheral portion of the ring-shaped core 30, a space portion 33 having a substantially circular cross section is formed from the upper surface to the lower surface at two locations facing each other in the diameter direction. When the drum core 20 is inserted into the ring core 30, the space 33 formed in the ring core 30 and the groove 25 formed in the drum core 20 face each other.

  Each metal terminal 40 has a strip-shaped portion 41 covering one outer side surface of the ring-shaped core 30 and two corner portions adjacent to the one outer side surface, and an upper portion disposed so as to sandwich these corner portions from above and below. It has bent portions 42a and 42b (which constitute the upper portion of the bent portion) and lower bent portions 42c and 42d. Further, of the upper bent portions 42a and 42b of each metal terminal 40, the upper bent portion 42b corresponding to one corner is cut to electrically connect the end portions 21a and 21b of the winding 21. A groove 43 is formed. Further, the lower bent portions 42c and 42d are substantially hexagonal mounting portions.

  In order to assemble the surface mount coil 10 according to the present embodiment, first, the winding 21 is wound around the winding shaft portion 22 of the drum-type core 20, and the end portions 21a and 21b of the winding 21 are pulled out to the outside. .

  On the other hand, the metal terminals 40 are attached to one outer side surface of the ring core 30 and two corners adjacent to the one outer side surface. Similarly, the metal terminal 40 is attached to the other outer surface of the ring-shaped core 30 and two corners adjacent to the other outer surface. At this time, the upper bent portions 42a and 42b are positioned at the upper corners of the ring-shaped core 30, and the lower bent portions 42c and 42c of the metal terminal 40 are placed in the fitting recesses 32 provided at the lower corners. 42d is fitted. In this way, the outer surface and corners of the ring-shaped core 30 are surrounded by the band-like part 41 of the metal terminal 40, and each corner is viewed from above and below by the upper bent parts 42a and 42b and the lower bent parts 42c and 42d. It will be in the state where it was pinched.

  Subsequently, the drum core 20 is inserted into the ring core 30 from the upper part of the ring core 30 from the lower collar part 24 side. At this time, the groove portion 25 of the drum core 20 is positioned above the space portion 33 of the ring core 30, and the end portions 21 a and 21 b of the winding 21 are positioned in the cut groove 43. At this time, the lower collar portion 24 of the ring-shaped core 30 is supported from below by a part of the outer peripheral portion thereof by the downward bent portions 42c and 42d. Then, the upper bent portion 42b and the end portions 21a and 21b of the winding 21 are bonded by soldering or the like in a state where the end portions 21a and 21b of the winding 21 are partially fitted in the kerf 43. Electrically connected by means.

  The band-like portion 41 of the metal terminal 40, the upper bent portions 42a and 42b, and the lower bent portions 42c and 42d are preferably attached in close contact with the outer surface and corner portions of the ring core 30. Thereby, the thermal conductivity between the ring-type core 30 and the metal terminal 40 increases, and the heat dissipation effect can be enhanced. Furthermore, it is preferable to interpose a heat conductive member such as a heat conductive silicon resin between the metal terminal 40 and the outer surface and corners of the ring core 30. Thereby, the thermal conductivity between the ring core 30 and the metal terminal 40 can be further enhanced.

  Further, in the surface mount type coil 10 of the present embodiment, the corner of the drum core 20 is notched, and further, the outer surface and corner of the drum core 20 are surrounded by the metal terminals 40. Even when external vibration or impact is applied, there is no possibility that the drum-type core 20 is damaged, and in particular, it can be optimally used as the surface-mounted coil 10 for vehicle loading.

  Next, a second embodiment of the surface mount coil according to the present invention will be described. 5 and 6 show a surface mount coil according to a second embodiment of the present invention. FIG. 5 is a perspective view of the coil as viewed from above, and FIG. 6 is a perspective view of the coil as viewed from below. It is. The surface-mounting coil according to the second embodiment is common in many parts to the surface-mounting coil according to the first embodiment described above. Therefore, in the following description, portions different from the first embodiment will be described in detail, and descriptions of common portions will be omitted as appropriate. In FIGS. 5 and 6, by using a number obtained by adding 100 to the numbers used in FIGS. 1 to 4, the correspondence between the constituent elements of the second embodiment and the first embodiment is shown. did.

  As shown in FIG. 5, the surface mount type coil 110 according to the second embodiment includes a winding wound around a winding shaft portion (not shown) on the outer periphery of the upper collar portion 123 of the drum core 120. Grooves 125 for pulling out the respective end portions 121a and 121b to the outside are formed at a total of four locations at intervals of ¼ circumference.

  In addition, in the inner peripheral portion of the ring-shaped core 130, space portions 133 (only two portions are shown) having a substantially circular cross section from the upper surface to the lower surface are formed at a total of four locations at intervals of ¼ circumference. When the drum core 120 is inserted into the ring core 130, the portion 133 faces each groove 125 formed in the drum core 120.

  Further, each upper bent portion 142a, 142b of the two metal terminals 140 is formed with a cut groove 143 for electrically connecting the ends of the windings, and each cut groove 143 has a drum core. Each groove portion 125 formed in 120 and each space portion 133 formed in the ring core 130 are opposed to each other.

  According to the surface mount type coil 110 configured as described above, the number of turns of the winding can be adjusted in units of a quarter turn, so the usage and specifications are changed, and the number of turns of the winding is changed. Even if it is necessary to do so, it is possible to flexibly cope with the change without changing the shape of the metal terminal 140.

  Further, as shown in FIG. 5, the inner end portions of the upper bent portions 142 a and 142 b are formed so as to contact the outer peripheral portion of the upper flange portion 123 of the drum core 120 across the groove portion 125. Accordingly, as shown in FIG. 6, an interval (clearance) having a predetermined width d can be secured between the outer peripheral portion of the lower collar portion 124 of the drum core 120 and the inner peripheral portion of the ring core 130. It has become.

  According to the surface mount type coil 110 configured as described above, the clearance between the outer peripheral portion of the lower flange portion 124 of the drum core 120 and the inner peripheral portion of the ring core 130 can be reliably performed. The inductance value can be stabilized, thereby improving the reliability and the usability.

  As in the first embodiment described above, the band-shaped portion 141 of the metal terminal 140, the upper bent portions 142a and 142b, and the lower bent portions 142c and 142d are formed on the outer surface and corners of the ring core 130. It is preferable to attach it in close contact with the portion, whereby the thermal conductivity between the ring core 130 and the metal terminal 140 is increased, and the heat dissipation effect can be enhanced. Furthermore, it is preferable to interpose a heat conductive member such as a heat conductive silicon resin between the metal terminal 140 and the outer surface and corners of the ring core 130, whereby the ring core 130 and the metal terminal 140 are arranged. The thermal conductivity between the two can be further increased.

  Similarly to the above-described first embodiment, the surface-mounted coil 110 of the second embodiment has a cut-out corner of the drum-type core 120, and further includes an outer surface of the drum-type core 120 and Since the corners are surrounded by the metal terminals 140, the drum core 120 is not damaged even when external vibration or impact is applied. 110 can be optimally used.

  In the surface mount coils 10 and 110 according to the first and second embodiments described above, the drum cores 20 and 120 and the ring cores 30 and 130 are formed of ferrite. The material is not limited to this, and can be selected from other common core materials. For example, materials such as permalloy, sendust, and iron carbonyl can be used, and these fine powders are compression molded. It is also possible to use a dust core.

  The surface mount coil of the present invention is not limited to a surface mount coil for loading on a vehicle, and can be used for various electronic devices.

1 is an exploded perspective view of a surface mount coil according to a first embodiment of the present invention. 1 is a longitudinal sectional view of a surface mount coil according to a first embodiment of the present invention. A perspective view of the ring-shaped core with metal terminals as seen from above A perspective view of the ring-type core with the metal terminal attached as seen from below. The perspective view of the state which looked at the surface mount type coil concerning a 2nd embodiment of the present invention from the upper surface The perspective view of the state which looked at the surface mount type coil which concerns on 2nd Embodiment of this invention from the lower surface

Explanation of symbols

10, 110 Surface mount type coil 20, 120 Drum type core 21 Winding 21a, 21b, 121a, 121b Winding end 22 Winding shaft part 23, 123 Upper collar part 24, 124 Lower collar part 25, 125 Groove part 30, 130 Ring-shaped core 31 Notch surface 32 Fitting recess 33, 133 Space 40, 140 Metal terminal 41, 141 Strip 42a, 42b, 142a, 142b Upper bent part 42c, 42d, 142c, 142d Lower bent part 43, 143 Width of kerf d interval

Claims (4)

A drum core having an upper collar part and a lower collar part at both ends of a winding shaft part for winding the winding;
A ring-type core that houses the drum-type core;
A surface mount type coil comprising two metal terminals mounted at positions facing each other on the outer peripheral surface of the ring core;
The drum core is formed such that the outer diameter of the upper collar part is larger than the outer diameter of the lower collar part,
The ring-shaped core has a substantially rectangular outer shape, and each corner is notched to form a notch surface, and the notch surfaces located diagonally are substantially parallel to each other,
The upper collar of the drum core is placed on the upper end of the ring core;
A space portion having a circular cross section is provided from the upper surface to the lower surface at least at two locations in the diametrical direction at the inner peripheral portion of the ring core, and the upper collar portion of the drum core is the ring shape. When placed on the upper end of the core, the winding is configured to be drawn from the space,
Each metal terminal includes a band-shaped portion covering one outer side surface of the ring core and two corners adjacent to the one outer side surface, and a bend arranged so as to sandwich these corner portions from above and below. Part
Of the bent portions of each of the metal terminals, the upper portion of the bent portion corresponding to at least one corner, and electrically connected to the end of the winding at a position corresponding to the space portion For this purpose, a cut groove into which a part of the end of the winding is fitted is formed,
By bringing the inner end of the upper part of each of the bent portions into contact with the outer peripheral portion of the upper collar portion of the drum core, the outer peripheral portion of the lower collar portion of the drum core and the ring mold A surface-mounting coil configured to ensure a predetermined width between the inner peripheral portion of the core .   2. The surface mount coil according to claim 1, wherein each of the metal terminals is attached in close contact with the outer surface and the corner of the ring core. 2. The surface mounting according to claim 1, wherein a cut groove is provided in an upper portion of all the bent portions of all the metal terminals that are in contact with the outer peripheral portion of the upper flange portion of the drum core. Type coil. 4. The surface mount coil according to claim 3, wherein the lower part of the bent part of all the metal terminals is a substantially hexagonal mounting part.

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