JP2013149868A - Reactor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reactor which is excellent in heat radiation performance, is easily fixed to another member with an easy operation, and is composed of a small number of components.SOLUTION: A reactor includes: a reactor body formed by winding a coil 20 around a U shaped core 11; and a cooling plate 30 fixing the reactor body. The U shaped core 11 and the coil 20 are fixed to the cooling plate 30 by fixing members 12. Insulating treatment is performed on a portion of a surface of the cooling plate 30, which faces the coil 20, by an insulation material 33. The coil 20 and the cooling plate 30 are disposed so that a clearance 34 is maintained between a surface of the insulation material 33 of the cooling plate 30 and a surface of the coil for suppressing partial discharging. The fixing members 12 and the cooling plate 30 may be composed of one metal plate P.

Description

  The present invention relates to a reactor in which a heat dissipation structure from a core or a coil is improved.

The following is known as a structure for fixing the reactor.
(1) A reactor is accommodated in a case, and resin is poured into the case to enclose the reactor (Patent Document 1).
(2) A heat transfer sheet is disposed on the lower surface of the coil, and the reactor is fixed to the mounting surface via the heat transfer sheet (Patent Document 2).
(3) A heat sink made of an insulating material is disposed on the coil contact surface on the cooling surface side of the reactor (Patent Document 3).

JP 2004-193322 A Japanese Patent No. 4645417 JP 2009-194198 A

  However, the prior art as described above has a drawback that a complicated configuration such as filling a resin around the coil or the core or disposing a heat sink is required. In particular, in the technique of Patent Document 1 in which a box-shaped aluminum case is filled with a resin, the cost of the resin as the filler is high and the number of filling steps is also increased. Moreover, the initial investment of the filling equipment is very expensive, and the installation space is also required. Furthermore, considering insulation and resin filling work, it is necessary to provide (minimum insulation distance + variation in component dimensions + minimum filling gap) between the coil and the aluminum case, and there is a limit to the heat dissipation of the coil.

  When the heat transfer sheet is used as in Patent Document 2, it is difficult to fix the coil. In that case, there is a method of fixing the coil by pushing the core, but considering the dimensional variation, the design is difficult, and the assembling work and the sheet sticking work are very difficult. In particular, regarding heat dissipation of the core with the heat dissipation sheet, heat dissipation becomes severe unless it is brought into contact with the case from the viewpoint of vibration. On the other hand, when contact is made with the case in consideration of heat dissipation, vibration is increased.

  As in Patent Document 3, the configuration in which the heat sink is provided between the coil that fixes the reactor and the coil needs to prepare a dedicated heat sink for each different member that fixes the reactor. It cannot be installed on a member.

  The present invention solves the problems of the prior art as described above, and its purpose is excellent in heat dissipation, can be fixed to other members by a simple operation, and has a small number of parts. It is to provide a reactor.

In order to achieve the above object, the reactor of the present invention is characterized by a combination of the following configurations.
(1) A reactor main body formed by winding a coil around a core and a cooling plate for fixing the reactor main body are provided.
(2) The core and the coil are fixed to the cooling plate by a fixing metal fitting.
(3) A portion of the cooling plate surface facing the coil is insulated by an insulating material.
(4) The coil and the cooling plate are disposed with a gap for suppressing partial discharge between the insulating material surface of the cooling plate and the coil surface.

  The said structure WHEREIN: Resin mold can be carried out with a core in the state which contacted the surface of the core with the fixing metal fitting. In addition, the fixing bracket and the cooling plate can be formed of a single metal plate, and the resin-molded core can be fixed to the metal plate together with the coil.

  As the insulating material provided on the surface of the cooling plate, an insulating sheet, ceramics, resin, coating agent and the like can be used, but those having good heat transfer performance are suitable. This insulating material is preferably formed in advance on the surface of the cooling plate by means of pasting, coating, or laminating.

  The gap necessary for suppressing the partial discharge varies depending on the rating of the reactor, but can be set to 0.3 to 0.75 mm in a reactor having a rating of 1 kV.

  In the present invention, when the reactor body and the cooling plate are fixed, since a minute gap and an insulating material are provided between the coil and the cooling plate, heat can be directly released from the coil to the cooling plate, and excellent heat dissipation can be achieved. Performance can be obtained, and partial discharge between the coil and the cooling unit can be effectively suppressed.

  In the present invention, since the reactor main body and the cooling plate are integrated by the fixing metal fitting, it is not necessary to arrange a dedicated heat transfer sheet or heat radiating plate for each installation location of the reactor, and the installation of the reactor is easy.

It is a disassembled perspective view which shows the reactor of 1st Embodiment. It is a perspective view of the assembly state of the reactor of 1st Embodiment. It is sectional drawing of the reactor of 1st Embodiment. It is an enlarged view of A part of FIG. It is a disassembled perspective view which shows the reactor of 2nd Embodiment. It is a perspective view of the assembly state of the reactor of 2nd Embodiment. It is sectional drawing of the reactor of 2nd Embodiment. It is an enlarged view of A part of FIG.

1. First Embodiment A first embodiment of the present invention will be described with reference to FIGS.

(1) Configuration As shown in FIGS. 1 and 2, the reactor according to the present embodiment includes a reactor body including a core 10 and a coil 20 wound around the core 10, and a cooling plate 30 that fixes the reactor body. Composed.

  The core 10 is formed by combining two U-shaped cores 11 with the end surfaces of the linear portions thereof facing each other. Each U-shaped core 11 includes a resin 13 together with a fixing member 12 for fixing the reactor body to the cooling plate 30. Is molded. In this case, the end surface 11 a of the U-shaped core 11 has the core surface exposed from the resin 13, and a magnetic path is formed between the end surface 11 a of the other U-shaped core 11 facing the U-shaped core 11. The other part of the U-shaped core 11 is covered with a resin 13 on the surface.

  The fixing member 12 has a central portion molded in the resin 13 and both end portions exposed from the resin 13. The exposed portion is provided with a screw insertion hole 15 for fixing the reactor main body to the cooling plate 30.

  As shown in the cross-sectional view of FIG. 3, the portion of the fixing member 12 in the resin 13 is bent in a U shape, and the upper surface 12 a contacts the surface of the U-shaped core 11, and part of the upper surface 12 a It is inserted between the U-shaped core 11 and the coil 20. Further, the lower surface 12 b of the fixing member 12 is exposed from the resin 13 and is in contact with the surface of the cooling plate 30. The height of the vertical portion 12 c of the fixing member 12 is approximately the same as the winding thickness of the coil 20. The dimension is such that a minute gap is formed between them.

  The reactor main body is configured by inserting the straight portions of the two U-shaped cores 11 having such a configuration into the coil 20 with both end faces thereof facing each other. In this case, the spacer 40 is inserted between the end faces 11a of the two U-shaped cores 11 to form a gap between the cores. The spacer 40 is not indispensable in the present embodiment, and may be a simple space as long as the gap dimensional accuracy is ensured.

  In this embodiment, the positions of the two U-shaped cores 11 inserted into the coil 20 are maintained by screwing the fixing members 12 of the U-shaped cores to the cooling plate 30. That is, screw holes 31 are provided at the four corners of the cooling plate 30, and fastening screws 32 inserted into the screw insertion holes 15 of the fixing members 12 are fastened to the screw holes 31, so that the cooling plate 30, the reactor body, Are fixed and the two U-shaped cores 11 are positioned.

  On the other hand, an insulating material 33 is provided on the surface of the cooling plate 30 facing the coil 20. As this insulating material 33, an insulating sheet, ceramics, resin, coating agent or the like can be used. In this embodiment, a polyimide resin layer containing an alumina filler in order to ensure good thermal conductivity. Is previously formed on the surface of the cooling plate 30 by a technique such as baking. Although the thickness of this insulating material 33 can be suitably selected according to the insulation characteristic etc. which are required for a reactor, it is 10-250 micrometers, for example, Preferably it is 10-80 micrometers.

  Between the surface of the insulating material 33 and the surface (outer peripheral surface) of the coil 20, as shown in the sectional view of FIG. 3 and the enlarged view of FIG. 34 is provided. The dimension of the gap 34 varies depending on the rating of the reactor, but can be set to 0.3 to 0.75 mm in a reactor having a rating of 1 kV. In the present embodiment, the coil 20 and the cooling plate 30 are fixed more firmly by filling the gap 34 with an adhesive.

(2) Effects The following effects are exhibited in the reactor according to the present embodiment having the above-described configuration.

(A) Since the fixing member 12 resin-molded together with the U-shaped core 11 is used to fix the cooling plate 30 and the reactor main body, there is no need to fill the resin between the cooling plate 30 and the reactor main body. Manufacturing is simplified.

(B) Since the outer peripheral surface of the coil 20 and the cooling plate 30 are arranged with a small gap 34 without covering the outer peripheral surface of the coil 20 disposed around the U-shaped core 11 with resin, The thermal resistance is dramatically reduced and the coil temperature can be reduced.

(C) Since a minute gap is provided between the surface of the coil 20 and the surface of the cooling plate 30, the occurrence of partial discharge in that portion can be effectively suppressed.

(D) Since the U-shaped core 11 is fixed to the cooling plate 30 via the fixing bracket 12, vibration due to a magnetic attractive force or the like is absorbed by the fixing bracket 12.

(E) Since the fixing bracket 12 is in contact with the U-shaped core 11 and the fixing bracket 12 is disposed between the U-shaped core 11 and the coil 20, the fixing bracket 12 effectively functions as a heat radiation path. . As a result, the resin filled between the reactor main body and the case becomes unnecessary, and it becomes unnecessary to use a box-like case, and the plate-like cooling plate 30 can be used. As a result, the configuration of the entire reactor is simplified.

(F) Since the insulating material 33 is integrated with the cooling plate 30 in advance, it is not necessary to separately prepare an insulating sheet or a heat radiating plate as in the prior art when the reactor is fixed to the installation place. The mounting work becomes simple. Further, the presence of the insulating material improves the withstand voltage.

2. Second Embodiment A second embodiment of the present invention will be described with reference to FIGS. Parts corresponding to the respective parts of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

(1) Configuration In the present embodiment, the cooling plate 30 and the fixing bracket 12 that are separated from each other in the first embodiment bend one metal plate P as shown in FIGS. 5 and 6. , Are integrally formed. In this case, the portion corresponding to the fixing metal 12 is not molded in the resin 13 and is exposed together with the portion corresponding to the cooling plate 30. Therefore, a U-shaped core 11 and a nut-shaped screw hole 31 a for fixing the U-shaped core 11 to the cooling plate 30 are molded in the resin 13.

  In this embodiment, the cooling plate 30 is formed in the center part of the metal plate P, and a pair of left and right coils 20 is placed on this part. On both sides of the cooling plate 30, U-shaped fixtures 12 are formed by bending the metal plate P. An upper surface 12 a of the U-shaped fixing bracket 12 is a mounting surface of the U-shaped core 11. Therefore, the contact portion with the upper surface 12 of the U-shaped core 11 is exposed without being covered with the resin 13.

  The lower surface 12 b of the U-shaped fixing member 12 has the same height as the surface of the cooling plate 30. The vertical portion 12 c of the fixing metal 12 functions as a leg that supports the U-shaped core 11, and its height is substantially the same as the thickness of the coil 20, and the U-shaped core 11 on which the coil 20 is mounted. Is mounted on the upper surface 12a, the dimension is such that a minute gap 34 is formed between the outer peripheral surface of the coil 20 (the lower surface of the coil) and the surface of the cooling plate 30 as in the first embodiment. ing.

  Also in the present embodiment, as shown in the cross-sectional view of FIG. 7 and the enlarged view of FIG. 8, an insulating material 33 similar to that of the first embodiment is provided on the facing surface of the coil 20 in the cooling plate 30.

  At the four corners of the U-shaped fixing member 12, tongue pieces 12 d having screw insertion holes 15 are provided by bending the four corners of the cooling plate 30 into an L shape. The tongue piece 12d is disposed on a nut-like screw hole 31a molded in the corner of the U-shaped core 11, and is integrally formed by a set screw 32 tightened into the nut-like screw hole 31a through the screw insertion hole 15. The fixed fixing metal 12 and the cooling plate 30 are fixed to the U-shaped core 11.

(2) Operational Effect In the present embodiment having such a configuration, the spacer 40 is arranged so that the end surfaces 11 a of the linear portions of the two resin-molded U-shaped cores 11 face each other inside the coil 20. The reactor body is configured by sandwiching them. Thereafter, the combined reactor main body is formed such that the lower surface of the coil 20 is positioned on the surface of the cooling plate 30 and the bottom surfaces of the two U-shaped cores 11 are positioned on the U-shaped fixing member 12. Set on top of each other and screw them together.

  In this case, it is the same as in the first embodiment that the insulating material 33 is disposed in advance on the cooling plate 30 portion of the metal plate P. Further, as in the first embodiment, the coil 20 and the cooling plate 30 can be fixed more firmly by filling or applying an adhesive with good heat conductivity in the gap 34 portion.

  If it does in this way, since the U-shaped part of fixing member 12 will be in direct contact with the exposed part of U type core 11, heat dissipation from a core will be performed effectively. Moreover, since the outer peripheral surface of the coil 20 and the cooling plate 20 are arranged close to each other with the minute gap 34 in the coil 20, heat dissipation from the coil 20 is also performed smoothly.

In the present embodiment, since the fixing bracket 12 and the cooling plate 30 are composed of one metal plate P, the number of parts can be reduced compared to the first embodiment in which the fixing bracket and the cooling plate are separate members. It becomes possible. In addition, since it is not necessary to mold the fixing metal 12 in the resin 13, the molding process of the U-shaped core 11 is simplified, and since there are few members to be placed in the mold, positioning in the mold is easy. The accuracy is also improved.
3. Other Embodiments The present invention is not limited to the above-described embodiments, and includes other embodiments as described below.

(1) In the above embodiment, the adhesive is filled between the surface of the coil 20 and the surface of the cooling plate 30, but a heat radiating sheet is provided instead of the adhesive, or a space portion in which nothing exists. Is also possible.

(2) The shape of the fixing member 12 is not limited to that shown in the drawing, and can be appropriately changed as long as a heat radiation path from the U-shaped core or coil can be formed.

(3) As a core constituting the reactor, in addition to a combination of two U-type cores, a U-type + I-type core obtained by bonding a U-type core and an I-type core through a gap can be used.

(4) If the gap dimension formed between the end surfaces 11a of the two U-shaped cores 11 can be properly managed by creating and integrating the fixing member 12 and the cooling plate 20 with high accuracy, the spacer 40 is It can be simply a gap of space without providing it.

(5) The gap for suppressing the partial discharge differs depending on the rating of the reactor and the like, and the numerical values in the embodiment do not limit the present invention. However, even when the specifications of the reactor are different, the configuration of the present invention can effectively suppress the occurrence of partial discharge at 0.05 mm or more and 1.5 mm or less.

(6) The present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

DESCRIPTION OF SYMBOLS 10 ... Core 11 ... U-shaped core 11a ... End surface 12 of U-shaped core ... Fixing member 12a ... Upper surface 12b ... Lower surface 12c ... Vertical part 12d ... Tongue piece 13 ... Resin 15 ... Screw insertion hole 20 ... Coil 30 ... Cooling plate 31, 31a ... Screw hole 32 ... Set screw 33 ... Insulating material 34 ... Minute gap 40 ... Spacer P ... Metal plate

Claims (6)

A reactor body formed by winding a coil around the core and a cooling plate for fixing the reactor body,
The core and the coil are fixed to the cooling plate by a fixing bracket,
The portion of the cooling plate surface facing the coil is subjected to insulation treatment with an insulating material,
The reactor, wherein the coil and the cooling plate are arranged with a gap for suppressing partial discharge between the insulating material surface of the cooling plate and the coil surface.   The reactor according to claim 1, wherein the fixing metal fitting is resin-molded together with the core in a state in which a part thereof is in contact with the surface of the core.   The reactor according to claim 1, wherein the fixing metal fitting and the cooling plate are constituted by a single metal plate, and a resin-molded core is fixed to the metal plate together with a coil.   The reactor according to any one of claims 1 to 3, wherein the insulating material provided on the surface of the cooling plate is any one of an insulating sheet, ceramics, resin, and coating agent, or a combination thereof. .   The reactor according to any one of claims 1 to 4, wherein the insulating material is formed on a surface of the cooling plate in advance before fixing the reactor main body to the cooling plate. The reactor according to any one of claims 1 to 5, wherein a gap for suppressing the partial discharge is 0.05 mm or more and 1.5 mm or less.

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