JP2013229527A - Reactor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reactor which improves heat radiation performance from a coil around which a conductor foil is wound.SOLUTION: A reactor includes: soft magnetic cores 31, 32; coils 51, 52 around which conductor foils are wound; a conductive case; conductive heat transfer parts 71, 72; and insulation parts 61, 62 having electric insulation properties. The soft magnetic cores 31, 32 and the coils 51, 52 are housed in the case. The insulation parts 61, 62 are disposed on end surfaces of the coils 51, 52 in a winding axial direction. Parts of surfaces of the heat transfer parts 71, 72 contact with the end surfaces through the insulation parts 61, 62, and the heat transfer parts 71, 72 have heat transfer paths to the case.

Description

  The present invention relates to a reactor that is a passive element using a coil.

  Patent Document 1 discloses a configuration in which a magnetic gap is provided in the center of the EE core and a foil wound coil is provided in the center.

  Further, Patent Document 1 describes a foil-wound coil configured to avoid the vicinity of the magnetic gap because leakage magnetic flux in the vicinity of the core magnetic gap causes eddy current in the foil-wound coil and AC loss increases.

JP-T-2007-53328

  In an inductor provided with a coil and a magnetic core wound with a conductive foil as disclosed in Patent Document 1, heat is generated inside the foil-wound coil due to DC resistance loss and eddy current loss. Especially in a reactor for high power applications, the conductive foil is used. Although heat dissipation from a coil wound around is important, Patent Document 1 has a problem that heat dissipation of a coil wound around a conductor foil is not sufficiently considered.

  Therefore, the objective of this invention is providing the reactor which improved the heat dissipation from the coil which wound the conductor foil.

  To solve the above problems, the present invention includes a soft magnetic core, a coil wound with a conductive foil, a conductive case, a conductive heat transfer portion, and an insulating portion having electrical insulation, and the soft magnetic core and coil Is housed in the case, the insulating part is disposed on the end surface of the coil in the winding axis direction, a part of the surface of the heat transfer part is in contact with the end face through the insulating part, and the heat transfer part is a heat transfer path to the case Resolve with a reactor that has

  The other part of the surface of the heat transfer section may have a heat transfer path to the soft magnetic core.

  Moreover, the minimum width of the cross section with respect to the direction of the heat transfer path in the heat transfer section may be larger than the thickness dimension of the case.

  Moreover, a part of end surface in a coil may contact a soft-magnetic core via an insulation part, and the soft-magnetic core may have the heat-transfer path | route to a case.

  The soft magnetic core has a square shape, the coil is a coil in which a first coil and a second coil are connected in parallel, and the first coil and the second coil are two opposite sides of the soft magnetic core. A part of the surface of the heat transfer section may be in contact with the end surfaces of both the first coil and the second coil via the insulating section.

  The case further includes a lid, the case has at least one opening, the lid is fixed to the opening, the lid has two first external connection terminals on the outside, and one or two second external connections on the inside. A terminal is provided, the first external connection terminal is connected to each innermost end portion of the conductor foil in the first coil and the second coil by a conductor, and the second external connection terminal is connected to the first coil and the second coil. Each conductor foil outermost peripheral end in the second coil is connected by a conductor, and the conductor in the second external connection terminal is routed in a direction close to each other, and the two first external connection terminals and two The second external connection terminals may be conductively connected to each other.

  In addition, the inductance of the reactor when the DC superimposed current of 15 A is applied to the coil may be 70% or more of the inductance when the DC superimposed current is not applied.

  The soft magnetic core further includes a nonmagnetic metal member having a magnetic gap, fixed by an electrically insulating material so as to be close to the magnetic gap, and disposed along the direction of the magnetic path in the soft magnetic core, The member may be insulated by a part of the conductive path that circulates in the direction of the magnetic path.

  By this invention, the reactor which improved the heat dissipation from the coil which wound the conductor foil can be provided.

The perspective view which shows the 1st example of the reactor in this invention. Sectional drawing of the AA surface in FIG. 1 which shows the 1st example of the reactor in this invention. The perspective view which shows the 2nd example of the reactor in this invention. Sectional drawing of the BB surface in FIG. 3 which shows the 2nd example of the reactor in this invention.

  The present invention includes, for example, a soft magnetic core, a coil wound with a conductive foil, a conductive case, a conductive heat transfer portion, and an insulating portion having electrical insulation. Housed in the case, the insulating part is arranged on the end surface in the winding axis direction of the coil, a part of the surface of the heat transfer part is in contact with the end face through the insulating part, and the heat transfer part has a heat transfer path to the case. It is possible to take a reactor embodiment.

  A coil wound with a conductive foil has high thermal conductivity in the in-plane direction of the conductive foil. Therefore, since the heat conductivity with respect to the winding axis direction of the coil included in the in-plane direction of the conductor foil is also high, the winding axis direction of the coil can be obtained by bringing the heat transfer portion into contact with the end surface in the winding axis direction of the coil via the insulating portion. Heat can be radiated from the end surface to the case through the heat transfer section.

  The heat transfer path from the heat transfer unit to the case is, for example, integrally molding the heat transfer unit and the case, contacting the heat transfer unit and the case, or sandwiching an electrical insulator between the heat transfer unit and the case. This can be ensured.

  When the electric insulator is sandwiched between the heat transfer section and the case, the thickness of the electric insulator is preferably 1 mm or less in order to ensure sufficient heat transfer. The electrical insulator is preferably an inorganic substance such as alumina or a metal oxide, or contains an inorganic powder to improve thermal conductivity.

  Alternatively, the heat transfer section may be made of a metal such as aluminum, and an oxide film may be formed on the surface to ensure electrical insulation between the coil end face and the case.

  In Patent Document 1, the foil wound coil is configured so as to avoid the vicinity of the magnetic gap. However, since the cross-sectional area of the conductor foil in the vicinity of the magnetic gap is reduced, the direct current resistance loss is increased.

  Furthermore, unexpected leakage may occur due to leakage magnetic flux from the soft magnetic core entering an external member other than the coil. Particularly, a large loss occurs in an external component made of a magnetic material such as a Ni-plated terminal, a semiconductor such as a circuit component, or an external component having a complicated shape of conductivity.

  On the other hand, in the configuration of the present embodiment, when the leakage AC magnetic flux from the soft magnetic core surface intersects the inner peripheral surface of the coil or the case surface, an eddy current is generated in the vicinity thereof, and the magnetic flux in the direction opposite to the intersecting leakage magnetic flux. Occurs. Accordingly, the alternating magnetic field component of the leakage magnetic flux from the soft magnetic core surface is confined by the inner peripheral surface of the coil and the case surface, and loss due to the conductor foil inside the coil and the parts outside the case can be suppressed.

  In particular, it is desirable to minimize the DC resistance loss by using a coil having the same width and cross-sectional area in the winding axis direction from the start to the end of winding.

  As the conductor foil, for example, a copper foil or an aluminum foil having a thickness of 6 μm to 200 μm can be used. It is desirable to use a lightweight aluminum foil that does not oxidize as the conductor foil. However, if the terminal part connected to the outside is made of a material having a high contact potential with aluminum such as copper, contact between copper and aluminum It is desirable to prevent the contact portion from reacting with moisture, oxygen or the like by covering the portion with resin or the like.

  For example, aluminum, iron, stainless steel, or the like can be used as the material of the case, but nonmagnetic aluminum is desirable for confining the magnetic flux in the case. Even in a case using a magnetic material such as iron, the magnetic flux can be confined in the case even if an aluminum foil or an aluminum plate is attached to the inner surface as a nonmagnetic material.

  In order to prevent eddy current loss due to leakage magnetic flux from the soft magnetic core surface entering the coil, it is desirable to shield the leakage magnetic flux from the soft magnetic core on the inner peripheral surface of the coil with the innermost conductor foil.

  Therefore, it is desirable that the thickness of the conductor foil is thicker than the skin depth at the frequency of the AC component in the current flowing through the coil.

  Moreover, this invention can take embodiment which the heat-transfer part surface has a heat-transfer path | route to a soft-magnetic core.

  The heat transfer path from the heat transfer section to the soft magnetic core is, for example, integrally molding the heat transfer section and the soft magnetic core, contacting the heat transfer section and the soft magnetic core, or between the heat transfer section and the soft magnetic core. This can be ensured by sandwiching an electrical insulator between the two.

  If the heat inside the coil cannot be sufficiently dissipated from the case, the heat dissipation can be further improved by providing a path for transferring heat from the coil end face to the soft magnetic core.

  Moreover, this invention can take embodiment whose minimum width of the cross section with respect to the direction of the heat-transfer path | route in a heat-transfer part is larger than the thickness dimension of the said case.

  By taking a large cross-sectional area of the heat transfer section that connects the heat transfer path between the coil end face and the case, heat can be temporarily accumulated in the heat transfer section without trapping heat in the coil end face. Furthermore, if it has the path | route which heat-transfers from a heat-transfer part to a case via a soft-magnetic core, the heat dissipation effect from a coil end surface can be improved more.

  According to the present invention, the soft magnetic core has a square shape, the coil is a coil in which the first coil and the second coil are connected in parallel, and the first coil and the second coil are opposed to each other in the soft magnetic core. It is possible to take an embodiment in which a part of the surface of the heat transfer part is in contact with both end faces of both the first coil and the second coil via an insulating part.

  Copper loss is reduced by adopting a configuration in which the first coil and the second coil are connected in parallel, and the area of the end face is doubled compared to the case of one coil, so the heat transfer efficiency to the case is improved. To do.

  In particular, compared to the EE core configuration described in Patent Document 1, the area where the coil end face is exposed from the soft magnetic core is more than doubled, so the contact area to the heat transfer part via the insulating part is increased. And the heat transfer efficiency to the case can be significantly improved.

  According to the present invention, the case has at least one opening, and the opening is provided with two first external connection terminals on the outside and one or two second external connection terminals on the inside. The terminal is connected to the innermost peripheral edge of each conductor foil in the first coil and the second coil by a conductor, and the second external connection terminal is each conductor foil in the first coil and the second coil. The outermost peripheral end is connected to the conductor, and the conductor in the second external connection terminal is routed in a direction close to each other, and the two first external connection terminals and the two second external connection terminals are conductively connected to each other. Can be taken as an embodiment of the reactor.

  Since the outer first outer connection terminal is connected by the conductor at the innermost peripheral end portion of the conductor foil, the conductor can take an insulation distance corresponding to the thickness of the coil between the conductor and the case.

  On the other hand, the conductors routed from the two second external connection terminals on the inner side are each routed to the outermost peripheral end portion of the conductor foil and come close to each other, but are electrically conductively connected with the same polarity. There is no need to ensure insulation.

  Accordingly, the two second external connection terminals on the inner side may be integrated into one second external connection terminal.

  Further, the present invention can take an embodiment in which the inductance when a DC superimposed current of 15 A is applied to the coil is 70% or more of the inductance when the DC superimposed current is not applied.

  The alternating magnetic field induced in the soft magnetic core by energizing the coil with an alternating current of 15 A or more periodically reaches a maximum value of about 0.2 Tesla or more, and the amplitude of the magnetic field is about 0.2 Tesla or more. Therefore, the magnetic material and the magnetic gap are configured so that the soft magnetic core does not cause magnetic saturation. Further, when a large alternating current used for such a boosting reactor of 500 kHz or less is applied to the coil, heat dissipation from the coil end surface is particularly required.

  In a reactor that is used for noise filters of 500 kHz or less, or for boosting and noise filter applications, the resonant frequency of the coil needs to be 500 kHz or more. Therefore, the relative dielectric constant of the insulating separator wound together with the conductor foil is It is desirable that it is 10 or less.

  The present invention further includes a non-magnetic metal member that has a magnetic gap, is fixed by an electrically insulating material so as to be close to the magnetic gap, and is disposed along the direction of the magnetic path in the soft magnetic core. The metal member may take an embodiment in which the metal member is insulated by a part of the conductive path that circulates in the direction of the magnetic path. Although a metal plate or the like may be newly provided as the metal member, the case or the heat transfer unit may also serve as the metal member.

  The soft magnetic core has a large leakage flux from the magnetic gap, so the magnetic field component of the leakage flux is confined by a paramagnetic or diamagnetic metal member such as aluminum, copper, or nickel alloy, and the loss due to external members is minimized. Can be suppressed. In addition, as for the thickness of a metal member, it is desirable that it is thicker than the skin depth in the frequency of an alternating current component among the electric currents supplied to a coil.

  Here, since the metal member is insulated by a part of the conductive path that circulates in the direction of the magnetic path, a short ring that restricts the magnetic path inside the soft magnetic core is not configured.

  In addition, when an alternating current is applied to the coil, a magnetic attractive force periodically acts on the surfaces of the soft magnetic cores facing each other through the magnetic gap, and the vicinity of the magnetic gap particularly vibrates greatly. In particular, noise occurs when the frequency of such vibrations is in the audible range.

  However, if a metal member is fixed with an electrically insulating material so as to be close to the magnetic gap, such vibrations in the audible range are suppressed by the rigidity of the metal member and the electrically insulating material, and resonance is performed up to a higher frequency than the audible range. Noise can be suppressed by increasing the vibration frequency.

  In particular, it is desirable that the electrically insulating material has viscoelasticity because vibration itself can be attenuated.

  Further, the inside of the case may be filled with a liquid such as resin or oil together with the soft magnetic core and the coil.

(Embodiment 1)
FIG. 1 is a perspective view showing a first example of a reactor in the present invention.

  The reactor 1 includes a case including a side wall 11, a mounting plate 12, a flange portion 13, and a bottom plate (not shown), an insulating plate 14 having electrical insulation, and a lid provided with a rigid reinforcing plate 15. A magnetic core is enclosed. The case and the lid are fixed by an assembly screw 16.

  The insulating plate 14 is provided with the external connection terminal 2.

  2 is a cross-sectional view of the AA plane in FIG. 1 showing a first example of a reactor in the present invention.

  The coils 51 and 52 are respectively routed to the winding start end portion of the conductor foil and the conductor portion 21 is provided to the winding end end portion and the conductor portion 22 is provided. The routing conductor portions 21 and 22 are externally provided. The connection terminal 2 is conductively connected. As a method for such a conductive connection, for example, a screw thread is formed on the inside of the case of the external connection terminal 2, and the conductor portions 21 and 22 are tightened by being routed by a nut and a washer.

  In this case, out of the four external connection terminals 2, the outer two external connection terminals 2 are routed away from the adjacent external connection terminals 2 and fixed so that the conductor portion 21 is routed. Since the connection terminal 2 is routed in the direction close to each other and fixed so that the conductor portion 21 is routed, the lead conductor portion 21 and the lead conductor portion 22 are separated from each other. 21 and 22 are desirable because mutual insulation can be secured.

  Of the four external connection terminals 2, the routing conductor portion 21 connected to the outer two external connection terminals 2 is routed to the winding start end portion in the vicinity of the inner peripheral surfaces of the coils 51 and 52. Therefore, the distance for ensuring the electrical insulation between the side wall 11 in the case can be taken.

  In addition, it is desirable that the insulating portions with respect to the soft magnetic core 31 can be secured by being fastened and fixed to the external connection terminals 2 so that the lead conductor portions 21 and 22 are separated from the soft magnetic core 31.

  Further, when two coils 51 and 52 are connected in parallel, out of the four external connection terminals 2, the inner two external connection terminals 2 and the outer two external connection terminals 2 have the same polarity, so It is possible to prevent a failure caused by short-circuiting of the lead conductor portions 22 in the two external connection terminals 2. Of course, the two coils 51 and 52 may be connected in series without being connected in parallel, or individually connected to a circuit or the like.

  In addition, mutual insulation may be ensured by covering the surfaces of the soft magnetic core 31 and the routing conductor portions 21 and 22 with an insulator.

  Moreover, you may provide the insulation partition plate which mutually insulates the two routing conductor parts 22 inside.

  The magnetic gap material 4 is sandwiched between the magnetic legs of the U-shaped soft magnetic cores 31 and 32, and the two soft magnetic cores form a square shape.

  Here, the soft magnetic core can be composed of, for example, a compacted core obtained by compacting metal magnetic powder such as MnZn ferrite, amorphous foil wound core, laminated electrical steel sheet, Fe-Si, or the like.

  In particular, laminated magnetic steel sheets and compacted cores that have a high saturation magnetic flux density and a low effective relative permeability have low leakage flux from the magnetic gap, and vibration and noise due to the current flowing through the coil. Is also desirable.

  In addition, since the relative magnetic permeability is low if it is a soft magnetic core such as a laminated magnetic steel sheet or a powder molded core, the magnetic gap material 4 may be replaced with an adhesive layer for bonding the soft magnetic cores.

  Coils 51 and 52 in which a conductive foil and an insulating separator are alternately wound are provided in the magnetic gap portion of the soft magnetic core. The coils 51 and 52 may be accommodated in a bobbin for ensuring insulation between the soft magnetic cores 31 and 32 and the case. If the bobbin which accommodates the coils 51 and 52 is comprised with a material with high heat conductivity, it can also be set as the heat-transfer path | route from a coil to a case like the heat-transfer parts 71 and 72. FIG.

  In addition, in order to prevent magnetic saturation in a noise filter application or a noise filter application that also serves as a booster, such as used in a power conversion circuit, where a large current of 15 A or more is temporarily applied to the coil, soft magnetism is used. The effective permeability including the magnetic gap in the core is desirably 150 or less in terms of relative permeability.

  An insulating portion 61 is provided on the end surfaces of the coils 51 and 52 in the winding axis direction, and the insulating portion 61 is further in contact with the heat transfer portion 71.

  The heat transfer section 71 is further in contact with the soft magnetic core 32, the bottom plate 17 and the side wall 11 in the case.

  The heat transfer section 71 is a member that supports the coils 51 and 52, and from the end faces of the coils 51 and 52 to a part of the heat transfer path T0 to the bottom plate 17 via the soft magnetic core 32, to the bottom plate 17 in the case. The heat transfer path T1 and the heat transfer path T2 to the side wall 11 are provided. The dimension W1 in the direction perpendicular to the direction of the heat transfer path T1 in the heat transfer part 71 is larger than the thickness dimension of the bottom plate 17, and the dimension W2 in the direction perpendicular to the direction of the heat transfer path T2 in the heat transfer part 71. This is desirable because it can be temporarily accumulated in the heat transfer section 71 without causing heat to be accumulated in the end faces of the coils 51 and 52 by making it larger than the thickness dimension of the side wall 11.

  A heat transfer section 72 is provided on the end face of the coils 51 and 52 on the lid side via an insulating section 62. The heat transfer part has an extension part 721 to the inner peripheral surface of the coils 51 and 52, and the extension part 721 is coupled to the magnetic gap material 4 and the soft magnetic cores 31 and 32 via the insulating part 63.

  Further, the heat transfer section 72 is in contact with the side wall 11 in the case, and serves as a heat transfer path from the end surfaces and inner peripheral surfaces of the coils 51 and 52 to the side wall 11 in the case.

  By applying an alternating current to the coils 51, 52, the soft magnetic cores 31, 32 have a magnetic force that sandwiches the magnetic gap material 4. However, since the extension part 721, the soft magnetic cores 31 and 32, and the magnetic gap material 4 are fixed via the insulating part 63, vibration due to the above-described magnetic force is suppressed.

  Further, if the extension 721 is a rigid metal conductor such as aluminum, the AC magnetic field component of the leakage magnetic flux from the vicinity of the magnetic gap material 4 is prevented from entering the coils 51 and 52, and eddy current loss is also suppressed. The

  The leakage magnetic flux from the soft magnetic cores 31 and 32 causes a large eddy current loss when it enters a conductor plate or a semiconductor thinner than the skin depth, but it is thicker than the skin depth and is distributed by a metal that is a non-magnetic good conductor. Eddy current loss is reduced when the current is limited.

  Therefore, eddy current loss can be reduced even when the innermost conductor foil of the coils 51 and 52 is thicker than the skin depth.

  The soft magnetic core 31 and the heat transfer part 72 are pressed from the lid side by the pressing plate 8. That is, the coils 51 and 52 are sandwiched and fixed between the presser plate 8 and the bottom plate 17 directly via the heat transfer portions 71 and 72 and the insulating portions 61 and 62, respectively.

  In addition, a reinforcing portion 111 is provided on the side wall 11 of the case by integral molding or the like, and the pressing plate 8, the insulating plate 14, and the reinforcing plate 15 are fixed to the reinforcing portion 111 with an assembly screw 16.

  Therefore, since the coils 51 and 52 and the soft magnetic cores 31 and 32 are firmly fixed by the configuration of the present embodiment, it is possible to prevent positional displacement due to vibration or impact from the outside of the case.

  The inside of the case may be filled with an insulating liquid such as resin or oil. In particular, it is desirable that the frequency causing the resonant vibration of the soft magnetic cores 31 and 32 is made higher than the audible range by hardening the periphery of the soft magnetic cores 31 and 32 with a rigid resin. Further, it is desirable that the space between the case side wall 11 and the bottom plate 17 is filled with an insulating liquid, so that vibration generated from the periphery of the soft magnetic cores 31 and 32 can be absorbed. Instead of the insulating liquid, it may be filled with a viscoelastic substance such as a gel, an adhesive, or rubber.

  When filling the inside of the case with an insulating liquid such as oil, the insulating plate 14 in the lid has a flexible layer such as rubber and a rigid body such as a composite of glass, resin, or insulating paper solidified with resin. By configuring the two layers of the layers so that the flexible layer is in contact with the reinforcing plate 15, the flexible layer in the insulating plate 14 improves the sealing performance of the insulating liquid, and the rigid layer Since strength can be secured, it is desirable.

  Moreover, you may use as the heat-transfer parts 71 and 72 what performed the anodizing process to the aluminum material. The aluminum anodized film can provide some electrical insulation between the coil, the soft magnetic core, and the side wall 11 and the bottom plate 17 of the case. Therefore, it is desirable to provide the terminal portion necessary for anodization in a portion not in contact with a conductor such as a coil, a soft magnetic core, and a case.

  Further, it is desirable that the presser plate 8 is made of an inorganic substance having a high thermal conductivity or a metal such as aluminum because a heat transfer path from the soft magnetic core 31 and the heat transfer portion 72 to the side wall 11 in the case can be formed. As for the pressing plate 8, it is desirable to secure an electric insulation to some extent by using an anodized aluminum material.

(Embodiment 2)
FIG. 3 is a perspective view showing a second example of the reactor in the present invention.

  As in the first embodiment, the reactor 1 includes a case including a side wall 11, a mounting plate 12, and a bottom plate (not shown), and a lid including an insulating plate 14 having electrical insulation and a rigid reinforcing plate 15. ing. However, the case and the lid are different from the first embodiment in that the lid is fixed from the case opening side by the fixing portion 131.

  Note that the external connection terminals 2 are installed on the insulating plate 14 as in the first embodiment.

  4 is a cross-sectional view of the BB surface in FIG. 3 showing a second example of the reactor in the present invention.

  As in the first embodiment, the coils 51 and 52 are routed to the winding start end portion of the conductor foil and the conductor portion 21 is provided at the winding end end portion, and the conductor portion 22 is provided to the external connection terminal 2. And conductively connected. The external connection terminal 2 may be conductively connected by, for example, forming a bolt by being threaded on the inside of the case, and drawing the nut with a nut and washer to tighten the conductor portions 21 and 22.

  Unlike the first embodiment, the magnetic gap material 4 is sandwiched between the rectangular parallelepiped block-type soft magnetic cores 33, 34, 35, and 36, and the four soft magnetic cores form a square shape.

  Since the arrangement of the coils 51 and 52, the insulating portion 61, and the heat transfer portion 71 is the same as that of the first embodiment, a heat transfer path is formed from the end faces of the coils 51 and 52 to the bottom plate 17 and the side wall 11 in the case, and heat transfer is simultaneously performed. The part 71 supports the coils 51 and 52 via the insulating part 61.

  Moreover, since the arrangement | positioning of the insulation part 62 and the heat-transfer part 72 is the same as that of Embodiment 1 also about the end surface by the side of the lid in the coils 51 and 52, the heat-transfer path | route from the coil 51 and 52 end surface to the side wall 11 in a case is provided. At the same time, the heat transfer section 72 supports the coils 51 and 52 from the lid side via the insulating section 62.

  On the other hand, the heat transfer part 71 is connected to the soft magnetic cores 34 and 35 and the magnetic gap material 4 via the insulating part 631, and the heat transfer part 72 is connected to the soft magnetic cores 33 and 34 via the insulating part 632. This is different from the first embodiment in that it is coupled to the magnetic gap material 4.

  By applying alternating current to the coils 51 and 52, the soft magnetic cores 33 to 36 have a magnetic force that sandwiches the magnetic gap material 4. However, since the heat transfer parts 71 and 72, the soft magnetic cores 33, 34, and 35 and the magnetic gap material 4 are fixed via the insulating parts 631 and 632 with the above configuration, vibration due to the magnetic force is suppressed. .

  Moreover, if the heat transfer parts 71 and 72 are metal members, such as rigid aluminum, the leakage magnetic flux from the magnetic gap material 4 vicinity is confined by the heat transfer parts 71 and 72, and an eddy current loss is also suppressed.

  As in the first embodiment, the soft magnetic core 33 and the heat transfer portion 72 are pressed from the lid side by the pressing plate 8. That is, the coils 51 and 52 are sandwiched and fixed between the pressing plate 8 and the bottom plate 17 directly via the heat transfer portions 71 and 72 and the insulating portions 61 and 62, and the soft magnetic cores 33 to 36 and the magnetic gap material 4 are fixed. .

  Unlike the first embodiment, the above components are assembled together with the insulating plate 14, the reinforcing plate 15, and the lid having the external connection terminal 2, and then housed inside the case, and the side wall 11 near the opening in the case is directed inward. The fixing part 131 is provided by folding it back and the lid is fixed.

  Therefore, as in the first embodiment, the coils 51 and 52 and the soft magnetic cores 33 to 36 are firmly fixed by the configuration of the present embodiment, so that it is possible to prevent positional displacement due to vibration and impact from the outside of the case. The

DESCRIPTION OF SYMBOLS 1 Reactor 2 External connection terminal 51, 52 Coil 8 Holding plate 11 Side wall 12 Mounting plate 13 Insulating plate 15 Reinforcement plate 16 Assembly screw 17 Bottom plate 21, 22 Leading conductor part 31, 32, 33, 34, 35, 36 Soft magnetic core 4 Magnetic gap material 61, 62, 63, 631, 632 Insulating part 71, 72 Heat transfer part 111 Reinforcement part 131 Fixing part 721 Extension part T0, T1, T2 Heat transfer path W1, W2 Dimensions

Claims (8)

A soft magnetic core,
A coil wound with a conductive foil;
A conductive case;
A conductive heat transfer section;
Insulating part having electrical insulation,
The soft magnetic core and the coil are housed in the case;
The insulating portion is disposed on an end surface of the coil in the winding axis direction,
A part of the surface of the heat transfer part is in contact with the end face through the insulating part,
The heat transfer section has a heat transfer path to the case.   2. The reactor according to claim 1, wherein another part of the surface of the heat transfer part has a heat transfer path to the soft magnetic core.   The reactor according to claim 1, wherein a minimum width of a cross section with respect to a direction of a heat transfer path in the heat transfer unit is larger than a thickness dimension of the case. A part of the end face of the coil is in contact with the soft magnetic core through the insulating portion,
The reactor according to any one of claims 1 to 3, wherein the soft magnetic core has a heat transfer path to the case. The soft magnetic core has a square shape,
The coil is a coil in which a first coil and a second coil are connected in parallel;
The first coil and the second coil are respectively wound around two opposing sides of the soft magnetic core,
The part of the surface of the heat transfer part is in contact with the end face of both the first coil and the second coil via the insulating part. The reactor described in Crab. In addition, with a lid,
The case has at least one opening;
The lid is fixed to the opening;
The lid is provided with two first external connection terminals on the outer side and one or two second external connection terminals on the inner side,
The first external connection terminal is connected to the innermost peripheral edge of each conductor foil in the first coil and the second coil by a conductor,
The second external connection terminal is connected to the outermost peripheral edge of each of the conductor foils in the first coil and the second coil by a conductor,
The conductors in the second external connection terminals are routed in directions close to each other,
The reactor according to claim 5, wherein the two first external connection terminals and the two second external connection terminals are conductively connected to each other.   7. The inductance according to claim 1, wherein an inductance of the reactor when a DC superimposed current of 15 A is applied to the coil is 70% or more of an inductance when the DC superimposed current is not applied. 8. Reactor. The soft magnetic core has a magnetic gap;
A non-magnetic metal member fixed by an electrically insulating material so as to be close to the magnetic gap and disposed along the direction of the magnetic path in the soft magnetic core;
The reactor according to any one of claims 1 to 7, wherein the metal member is insulated by a part of a conductive path that circulates in a direction of the magnetic path.

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