JP2016119398A - Reactor structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reactor structure which enables downsizing while securing the insulation quality between a coil and a case of a reactor.SOLUTION: A reactor structure 100 includes a reactor 10, a case 20 housing the reactor 10, and a potting material 30 filling the case 20 and supporting the reactor 10. The reactor 10 has cores 11, coils 12 wound around the cores 11, and a resin mold 14 covering the cores 11 and the coils 12. The resin mold 14 has: a side surface 14a which faces an inner side surface 21a of the case 20 while forming a space D therebetween; and an opening part 14b which exposes end parts of the coils 12, which face a bottom surface 22a of the case 20, to place the end parts in contact with the potting material 30. An edge part 14c of the opening part 14b of the resin mold 14 is embedded in the potting material 30.SELECTED DRAWING: Figure 1A

Description

  The present invention relates to a reactor structure used for in-vehicle applications and the like.

  For example, a reactor is used in a converter that is mounted on a vehicle such as a hybrid electric vehicle (HEV) or an electric vehicle (EV) and that steps up or down a voltage. The reactor has a coil wound around a core, and is fixed to the case via a potting material made of a resin material such as an epoxy resin. As a reactor support structure, a structure in which a reactor is supported on a case via a latent heat storage material having a melting point set within a specified temperature range of the reactor is known (see Patent Document 1 below).

JP 2013-38324 A

  In a reactor structure including a reactor and a case that supports the reactor, further downsizing and higher performance of the reactor are required. For example, in the conventional reactor structure 900 shown in FIG. 5A and FIG. Is supported in the case 920 by a potting material 930 having

  In order to reduce the size of such a conventional reactor structure 900, it is necessary to reduce the space between the coil 912 and the inner side surface 921a of the case 920. However, when the space between the coil 912 and the inner side surface 921a of the case 920 is reduced, the distance between the coil 912 and the inner side surface 921a of the case 920 becomes closer, and potting, which is the insulation distance between the coil 912 and the case 920. The creepage distance L along the surface 930a of the material 930 is shortened, and the insulation between the coil 912 and the case 920 may be reduced.

  5C, when the creeping distance L along the surface 930a of the potting material 930 is increased in order to ensure insulation between the coil 912 and the case 920, as in the modification of the conventional reactor structure 900 shown in FIG. It becomes difficult to reduce the size of the structure 900. Further, the space for filling the potting material 930 between the coil 912 and the case 920 is increased, and not only the heat dissipation from the coil 912 to the case 920 is lowered, but also the amount of use of the potting material 930 is increased and the material cost is increased. May rise.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a reactor structure that can be reduced in size while ensuring insulation between the coil of the reactor and the case.

  In order to achieve the above object, a reactor structure of the present invention is a reactor structure including a reactor, a case that accommodates the reactor, and a potting material that is filled in the case and supports the reactor. Has a core, a coil wound around the core, and a resin mold that covers the core and the coil, the resin mold facing the inner surface of the case with a space therebetween, An opening that exposes an end of the coil facing the bottom surface of the case and contacts the potting material; and an edge of the opening is embedded in the potting material.

  In the reactor structure of the present invention described above, the case is filled with a potting material that supports the reactor. Here, as the potting material, for example, a liquid curable resin material excellent in insulation and thermal conductivity can be used. Thereby, the heat dissipation of a reactor and the insulation with respect to a case can be improved. Moreover, since a potting material functions as an adhesive agent, the adhesiveness with respect to a resin mold and a case can be improved compared with a sheet-like heat radiating material. If the thermal conductivity of the potting material is higher than the thermal conductivity of the resin mold, the potting material can efficiently transfer the heat of the coil to the case, and the temperature rise of the reactor can be more effectively suppressed.

  Further, in the reactor structure of the present invention, the resin mold of the reactor has a side surface facing the inner side surface of the case with an interval, and an opening portion that exposes the end of the coil facing the bottom surface of the case and contacts the potting material. And have. Thereby, the heat of the coil exposed from the opening of the resin mold can be efficiently transmitted to the bottom surface of the case by the potting material, and the heat on the bottom surface of the case can be radiated from the inner side surface of the case to the outside air. Moreover, the insulation of a reactor can be improved with the space between the resin mold of a reactor and the inner surface of a case.

  Furthermore, in the reactor structure of the present invention, the edge of the opening of the resin mold is embedded in the potting material. Thus, the edge of the opening of the resin mold facing the bottom surface of the case is arranged on the bottom surface side of the case with respect to the surface of the potting material exposed in the space between the side surface of the resin mold and the inner side surface of the case. The Therefore, the insulation distance between the coil exposed to the opening of the resin mold and the case is the sum of creepage distances along the following surfaces. That is, the creepage distance along the edge of the opening from the coil to the side of the resin mold, the creepage distance along the side of the resin mold from the edge of the opening to the surface of the potting material, and the side of the case from the side of the resin mold It is the sum of the creeping distance along the surface of the potting material to the inner surface.

  Thus, the creepage distance, which is the insulation distance between the coil and the case, includes the creepage distance along the side surface of the resin mold, thereby ensuring the creepage distance between the coil and the case, The space between the inner surface and the inner surface can be reduced. In other words, the reactor structure of the present invention reduces the space between the coil and the inner surface of the case for the purpose of downsizing, and even if the creeping distance along the surface of the potting material exposed in the space decreases, The decrease can be supplemented by the creepage distance along the side surface of the resin mold.

  Therefore, according to the reactor structure of the present invention, the space between the coil of the reactor and the inner side surface of the case can be reduced to reduce the size, and the creepage distance between the coil and the case can be reduced by the side surface of the resin mold. It is possible to secure and prevent a decrease in insulation between the coil and the case. Moreover, the space for filling the potting material between the coil and the case is reduced due to the downsizing of the case, and not only the heat dissipation from the coil to the case is suppressed, but also the amount of potting material used is suppressed. Material costs can be reduced.

  As can be understood from the above description, according to the reactor structure of the present invention, it is possible to provide a reactor structure that can be reduced in size while ensuring insulation between the coil of the reactor and the case.

A sectional view showing roughly a reactor structure concerning an embodiment of the present invention. FIG. 1B is an enlarged cross-sectional view of the reactor structure shown in FIG. 1A. The expanded sectional view which shows the modification 1 of the reactor structure shown to FIG. 1B. The expanded sectional view which shows the modification 2 of the reactor structure shown to FIG. 1B. The expanded sectional view which shows the modification 3 of the reactor structure shown to FIG. 1B. Sectional drawing which shows the conventional reactor structure schematically. The expanded sectional view of the conventional reactor structure shown to FIG. 5A. The expanded sectional view of other conventional reactor structures.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a reactor structure of the present invention will be described in detail with reference to the drawings.

  FIG. 1A is a cross-sectional view schematically showing a reactor structure 100 according to an embodiment of the present invention. FIG. 1B is an enlarged cross-sectional view of the reactor structure 100 shown in FIG. 1A. The reactor structure 100 of the present embodiment includes a reactor 10, a case 20 that houses the reactor 10, and a potting material 30 that is filled in the case 20 and supports the reactor 10.

  The reactor 10 includes a core 11, a coil 12 wound around the core 11, a bobbin 13 for ensuring insulation between the core 11 and the coil 12, and the core 11 and the coil 12. And a resin mold 14 to be used. The resin mold 14 exposes the side surface 14a facing the inner side surface 21a of the side wall 21 of the case 20 with a space therebetween and the end of the coil 12 facing the bottom surface 22a inside the bottom wall 22 of the case 20 to expose the potting material 30. And an opening 14b to be brought into contact with. An edge 14 c of the opening 14 b of the resin mold 14 is embedded in the potting material 30.

  Accordingly, the resin mold 14 has a surface of the potting material 30 in which an end portion on the bottom surface 22a side of the case 20 including the edge portion 14c of the opening 14b is exposed in a space between the case 20 and the side surface 14a of the resin mold 14. It is arranged closer to the bottom surface 22a of the case 20 than 30a. Moreover, the edge part 14c of the opening part 14b of the resin mold 14 and the edge part of the coil 12 are covered with the potting material 30 with which the circumference | surroundings were filled.

  As the material of the core 11, for example, a material obtained by compression molding a powder of a soft magnetic material such as a metal such as iron or a metal oxide, or a material in which a nonmagnetic material such as ceramics or resin is interposed therebetween is used. it can. As the coil 12, for example, a copper rectangular wire or the like can be used. The material of the bobbin 13 can be selected from thermoplastic resin materials such as polyphenylene sulfide (PPS), polyamide (PA), and polyester (PE) (for example, PET, PBT, LCP).

  As a material of the resin mold 14, a thermoplastic resin having a melting point of 200 ° C. or more containing a filler can be used. As the thermoplastic resin, for example, a thermoplastic resin similar to the bobbin 13 can be selected. As a filler, 1 or more types can be selected from glass fiber (GF fiber), glass flakes, and a mineral component (talc, calcium carbonate, mica etc.), for example. The resin mold 14 of this embodiment uses a material in which GF fibers and mineral components are mixed in PPS resin, has a flexural modulus of 10 GPa or more and a flexural strength of 150 MPa or more. Further, the thermal conductivity of the resin mold 14 is, for example, 1.0 W / mK or less, for example, within a range of about 0.4 W / mK to 0.6 W / mK.

  The case 20 has a concave shape having a side wall 21 and a bottom wall 22, and the upper part is opened, and the potting material 30 and the reactor 10 are accommodated in the accommodating portion 23 inside the side wall 21 and the bottom wall 22. The case 20 supports the reactor 10 with the potting material 30 accommodated in the bottom of the accommodating portion 23, and has a gap D between the resin mold 14 covering the core 11 and the coil 12 of the reactor 10 and the inner side surface 21 a of the side wall 21. doing. The case 20 is made of, for example, a metal material such as aluminum or an aluminum alloy. The case 20 includes, for example, a refrigerant flow path for circulating a coolant such as cooling water (not shown) inside the bottom wall 22 and is cooled by the refrigerant flowing through the refrigerant flow path.

  The case 20 has a recess 22b on the bottom surface 22a, and the end of the coil 12 exposed from the opening 14b of the resin mold 14 of the reactor 10 is accommodated in the recess 22b. The bottom wall 22 of the case 20 includes a thin portion 22c that is thinned by forming the concave portion 22b, and a thick portion 22d that is thicker than the thin portion 22c around the concave portion 22b. By forming the recess 22b on the bottom surface 22a of the case 20, a step portion 22e that protrudes relatively toward the reactor 10 is formed around the recess 22b of the bottom surface 22a of the case 20. The step portion 22e is provided at a position facing the edge portion 14c of the opening portion 14b of the resin mold 14 of the reactor 10 with a space therebetween so as to fill an extra space between the coil 12 and the case 20.

As the potting material 30, for example, a liquid or paste-like curable resin material excellent in insulation and thermal conductivity can be used. In order to efficiently transfer the heat of the coil 12 of the reactor 10 to the case 20, the thermal conductivity of the potting material 30 is preferably higher than the thermal conductivity of the resin mold 14. If the potting material 30 is a moisture curing type and a room temperature curing type (one liquid type or two liquid mixing type), a silicone resin, an epoxy resin, and a urethane resin can be selected as the base resin. Moreover, the potting material 30 contains a metal oxide, an inorganic compound, etc., in order to improve heat conduction. The potting material 30 of the present embodiment uses a material containing 60 vol% of alumina filler in a silicone resin, the thermal conductivity is 1.5 W / mK or more, the insulation (volume resistivity) is 10 ¹² Ω · cm or more, Tracking performance is 600V or more.

  In order to support the reactor 10 with the potting material 30, for example, after filling the container 23 of the case 20 with a liquid or paste-like potting material 30, a predetermined interval is provided between the side wall 21 and the bottom wall 22 of the case 20. Reactor 10 is accommodated in case 20. Then, the end of the coil 12 exposed to the opening 14b of the resin mold 14 of the reactor 10 is brought into contact with the potting material 30, and the edge 14c of the opening 14b of the resin mold 14 is buried under the liquid level of the potting material 30. . Thereafter, the reactor 10 is fastened to the case 20 with a bolt (not shown), and the potting material 30 is cured.

  Alternatively, after the reactor 10 is accommodated in the case 20 and fastened to the case 20 with a bolt (not shown), the potting material 30 is filled between the reactor 10 and the case 20 and the edge of the opening 14b of the resin mold 14 is filled. The potting material 30 is cured by burying the portion 14 c under the liquid surface of the potting material 30. Thereby, the edge part 14c of the opening part 14b of the resin mold 14 of the reactor 10 can be embed | buried in the potting material 30. FIG.

  Hereinafter, the effect | action of the reactor structure 100 of this embodiment is demonstrated.

  As described above, the reactor structure 100 of the present embodiment includes the reactor 10, and the reactor 10 includes a resin mold 14 that covers the core 11 and the coil 12. The resin mold 14 has a side surface 14 a that faces the inner side surface 21 a of the case 20, and an opening portion 14 b that exposes the end of the coil 12 that faces the bottom surface 22 a of the case 20 and makes contact with the potting material 30. Yes.

  Compared with the case where a sheet-like heat dissipation material is used by filling the case 20 with a liquid or paste-like potting material 30 that functions as an adhesive and a heat dissipation material and contacting the reactor 10 with the potting material 30, the reactor 10 is used. And the adhesiveness of the potting material 30 with respect to the case 20 can be improved. In addition, by using the potting material 30 having a thermal conductivity higher than that of the resin mold 14, the potting material 30 can efficiently transfer the heat of the coil 12 to the case 20, thereby increasing the temperature of the reactor 10. Can be suppressed.

  Moreover, the reactor structure 100 of this embodiment has the space | interval D between the resin mold 14 of the reactor 10, and the inner surface 21a of the side wall 21 of the case 20. FIG. Thereby, the heat transmitted to the case 20 via the potting material 30 can be efficiently radiated from the side wall 21 of the case 20 to the outside air, and the temperature rise of the reactor 10 can be effectively suppressed.

  Here, the example of the conventional reactor structure is demonstrated for the comparison with the reactor structure 100 of this embodiment. FIG. 5A is a cross-sectional view schematically showing a conventional reactor structure 900. FIG. 5B is an enlarged cross-sectional view of the conventional reactor structure 900 shown in FIG. 5A. FIG. 5C is an enlarged cross-sectional view showing a modified example of the conventional reactor structure 900.

  In the conventional reactor structure 900 shown in FIGS. 5A and 5B, the lower end of the resin mold 914 that covers the core 911 and the coil 912 of the reactor 910, that is, the end 914c of the resin mold 914 that faces the bottom surface 922a of the case 920, The potting material 930 is opposed to the potting material 930 with a gap without contacting the potting material 930. Further, in the conventional reactor structure 900, the coil 912 exposed from the resin mold 914 and the inner side surface 921a of the case 920 face each other with a space therebetween, and the end portion of the coil 912 facing the bottom surface 922a of the case 920 is the case. It is supported by a potting material 930 filled between 920 and 920.

  In such a conventional reactor structure 900, when the space between the coil 912 and the inner side surface 921a of the case 920 is reduced for miniaturization, the coil 912 and the case along the surface 930a of the potting material 930 exposed in the space are reduced. The creepage distance L, which is the distance between the coil 912, that is, the insulation distance between the coil 912 and the case 920, may be reduced, and the insulation between the coil 912 and the case 920 may be deteriorated.

  Further, as in the modification of the conventional reactor structure 900 shown in FIG. 5C, if the creeping distance L along the potting material 930 is increased in order to ensure the insulation between the coil 912 and the case 920, it is difficult to reduce the size. In addition, the space for filling the potting material 930 between the coil 912 and the case 920 increases. In this case, not only the heat dissipation from the coil 912 to the case 920 is lowered, but the amount of the potting material 930 used is increased and the material cost may be increased.

  On the other hand, in the reactor structure 100 of the present embodiment shown in FIGS. 1A and 1B, the resin mold 14 faces the side surface 14a facing the inner side surface 21a of the case 20 with a gap D and the bottom surface 22a of the case 20. And an opening 14b that exposes the end of the coil 12 to be brought into contact with the potting material 30. The edge 14 c of the opening 14 b is embedded in the potting material 30.

  Thereby, the edge part 14c of the opening part 14b of the resin mold 14 which opposes the bottom face 22a of the case 20 is the surface of the potting material 30 exposed to the space between the side surface 14a of the resin mold 14 and the inner side surface 21a of the case 20. It is arranged closer to the bottom surface 22a of the case 20 than 30a. Therefore, the insulation distance between the coil 12 exposed to the opening 14b of the resin mold 14 and the case 20 is the sum of creeping distances L1, L2, and L3 along the following surfaces.

  That is, the insulation distance includes the creeping distance L1 along the edge 14c of the opening 14b from the coil 12 to the side surface 14a of the resin mold 14, and the resin mold from the edge 14c of the opening 14b to the surface 30a of the potting material 30. 14 is the sum of the creepage distance L2 along the side surface 14a of the resin 14 and the creepage distance L3 along the surface 30a of the potting material 30 from the side surface 14a of the resin mold 14 to the inner side surface 21a of the case 20.

  Thus, the creepage distance between the coil 12 and the case 20 is ensured by including the creepage distance L2 along the side surface 14a of the resin mold 14 in the creepage distance that is the insulation distance between the coil 12 and the case 20. However, the space between the coil 12 and the inner surface 21a of the case 20 can be reduced. In other words, the reactor structure 100 of the present embodiment reduces the space between the coil 12 and the inner side surface 21a of the case 20 for the purpose of downsizing, and the creepage distance along the surface 30a of the potting material 30 exposed in the space. Even if L3 decreases, the decrease can be supplemented by the creepage distance L2 along the side surface 14a of the resin mold 14.

  Therefore, according to the reactor structure 100 of the present embodiment, the space between the coil 12 of the reactor 10 and the inner side surface 21a of the case 20 can be reduced, and the coil 12 can be reduced by the side surface 14a of the resin mold 14. A creepage distance between the coil 12 and the case 20 can be ensured, and a decrease in insulation between the coil 12 and the case 20 can be prevented. Further, the space for filling the potting material 30 between the coil 12 and the case 20 is reduced due to the downsizing of the case 20, and not only the heat dissipation from the coil 12 to the case 20 is suppressed, but also the potting material 30. It is possible to reduce the material cost by suppressing the amount used.

  Moreover, in the reactor structure 100 of this embodiment, the case 20 has the recessed part 22b which accommodates the edge part of the coil 12 exposed from the opening part 14b of the resin mold 14 of the reactor 10 in the bottom face 22a, Around the recessed part 22b A step portion 22e that protrudes relatively toward the reactor 10 is formed. Further, the step portion 22e is provided at a position facing the edge portion 14c of the opening portion 14b of the resin mold 14 of the reactor 10 with a space therebetween so as to fill an extra space between the coil 12 and the case 20. Yes. Therefore, according to the reactor structure 100 of the present embodiment, the space for filling the potting material 30 between the coil 12 and the case 20 is reduced, and only a reduction in heat dissipation from the coil 12 to the case 20 is suppressed. In addition, the material cost can be reduced by suppressing the amount of the potting material 30 used.

  As described above, according to the reactor structure 100 of the present embodiment, it is possible to provide the reactor structure 100 that can be reduced in size while ensuring the insulation between the coil 12 of the reactor 10 and the case 20. . The present invention is not limited to the reactor structure 100 described in the present embodiment. Hereinafter, modifications 1 to 3 of the reactor structure 100 of the present embodiment will be described.

  2 to 4 are enlarged cross-sectional views showing modified examples 1 to 3 of the reactor structure 100 shown in FIG. 1B.

  In the first modification of the reactor structure 100 shown in FIG. 2, the resin mold 14 of the reactor 10 is curved along the curved surface of the coil 12. Moreover, the edge part 14c of the opening part 14b provided in the resin mold 14 may be formed in the curved surface form. In the second modification of the reactor structure 100 shown in FIG. 3, the lower end portion of the side surface 14 a adjacent to the edge portion 14 c of the opening portion 14 b of the resin mold 14 is formed in a curved shape that is opposite to the curved surface of the coil 12. Thereby, the edge part 14c of the opening part 14b of the resin mold 14 is extended toward the inner surface 21a of the case 20 rather than the side surface 14a. According to these modified examples, not only the same effect as the reactor structure 100 described above can be obtained, but also the creeping distance between the coil 12 and the case 20 can be increased.

  In the third modification of the reactor structure 100 shown in FIG. 4, a convex portion 14 d that protrudes toward the inner side surface 21 a of the case 20 is formed at the lower end portion of the side surface 14 a adjacent to the edge portion 14 c of the opening 14 b of the resin mold 14. Has been. According to this modification, not only the same effect as the reactor structure 100 described above is obtained, but also the creeping distance L1 along the edge portion 14c of the opening 14b of the resin mold 14 is extended, and the surface 30a of the potting material 30 is extended. The creeping distance L3 along can be shortened. Moreover, the space between the coil 12 and the case 20 can be reduced, and the amount of the potting material 30 used can be reduced.

  The embodiment of the present invention has been described in detail with reference to the drawings, but the specific configuration is not limited to this embodiment, and there are design changes and the like without departing from the gist of the present invention. They are also included in the present invention.

10 Reactor 11 Core 12 Coil 14 Resin Mold 14a Side 14b Opening 14c Edge 20 Case 21a Inner Side 22a Bottom 30 Potting Material 100 Reactor Structure D Interval

Claims (1)

A reactor structure comprising a reactor, a case that accommodates the reactor, and a potting material that is filled in the case and supports the reactor,
The reactor includes a core, a coil wound around the core, and a resin mold that covers the core and the coil.
The resin mold has a side surface facing the inner side surface of the case with a gap, and an opening that exposes the end of the coil facing the bottom surface of the case and contacts the potting material,
The reactor structure, wherein an edge of the opening is embedded in the potting material.

Images