JP2016184630A - Reactor and method of manufacturing reactor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reactor capable of reconciling good heat dissipation and noise reduction, and to provide a method of manufacturing the reactor.SOLUTION: A reactor includes a coil having a wound part formed by winding spirally, a magnetic core having a part disposed in the wound part, a metal member having a mounting surface of a combination body of the core and magnetic core, and an insulation layer provided on the mounting surface of the metal member, and bonding the wound part and metal member. The insulation layer is composed of a plurality of insulation materials containing resin and having different hardness, where hard regions composed of a hard insulation material, and soft regions composed of an insulation material softer than the hard insulation material exist alternately, when viewing in the axial direction of the wound part.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a reactor used for components of a power conversion device such as a vehicle-mounted DC-DC converter mounted on a vehicle such as a hybrid vehicle, and a manufacturing method thereof. In particular, the present invention relates to a reactor that can achieve both good heat dissipation and noise reduction, and a method for manufacturing the same.

  A reactor is one of the parts of a circuit that performs a voltage step-up operation or a voltage step-down operation. In Patent Documents 1 and 2, as a reactor used in a converter mounted on a vehicle such as a hybrid vehicle, a coil having a pair of winding portions (coil elements) formed by spirally winding a coil and an annular shape are used. An assembly in which a combination with a magnetic core is housed in a case and a sealing resin is filled in the case is disclosed. The winding part of the coil and the bottom plate part of the metal case are fixed by a bonding layer made of an insulating resin or an adhesive.

JP 2014-096463 A JP 2014-107294 A

  There is a demand for a reactor that can achieve both good heat dissipation and reduced noise.

  As described in Patent Documents 1 and 2, by joining the winding portion of the coil and the bottom plate portion of the metal case with a bonding layer such as an insulating resin, between the winding portion and the bottom plate portion. In addition to being able to improve insulation, it is possible to maintain a state in which the winding portion is disposed close to the bottom plate portion, and it is excellent in heat dissipation. By using a resin containing a ceramic filler having a high thermal conductivity as an insulating resin, heat dissipation is further improved. However, since the winding part is brought close to the bottom plate part, there is a problem that the vibration of the magnetic core caused by magnetostriction or the like is transmitted to the case through the winding part and the bonding layer, and noise may be generated. In particular, when the wound portion and the bottom plate portion are joined with a material containing a relatively hard resin such as an epoxy resin, the vibration of the magnetic core is more easily transmitted to the case. In addition, when some stress is applied to the bonding layer, the bonding layer made of the hard material described above may be cracked or peeled off. The heat dissipation is reduced due to peeling of the bonding layer, and noise is more likely to occur.

  Noise can be reduced if a sufficient gap is provided between the above-mentioned coil / magnetic core assembly and the bottom plate of the case, but the distance between the coil and the bottom plate increases and the heat dissipation decreases. Invite.

  If, for example, a material containing a relatively soft resin such as a silicone resin is used in place of the hard material described above, the soft material can absorb vibrations of the magnetic core described above, and noise reduction can be expected. However, the bonding layer made of a soft material may be deformed due to internal stress caused by temperature change, vibration or shock from the outside, or may be destroyed when subjected to a large shock. Due to deformation or destruction of the bonding layer, the heat dissipation may be reduced, or the noise reduction effect may not be obtained. Therefore, it is desired to improve durability against the action from the inside and the outside.

  In addition, a case where the bonding layer is repeatedly solidified after applying an adhesive or the like is laminated, or a plurality of adhesive layers are laminated, or an adhesive layer is provided on both sides of the insulating sheet described in Patent Document 1. It may be a structure laminated in the depth direction (hereinafter referred to as a vertically stacked structure). In this case, the insulation between the coil winding portion and the bottom plate portion of the metal case can be further enhanced, and a reduction in noise can be expected by increasing the distance between the winding portion and the bottom plate portion. However, in this case, the increase in the distance causes a decrease in heat dissipation. In addition, repeating the application and solidification increases the number of manufacturing steps, leading to a reduction in reactor productivity.

  Accordingly, one of the objects of the present invention is to provide a reactor that can achieve both good heat dissipation and noise reduction.

  Another object of the present invention is to provide a reactor manufacturing method capable of manufacturing a reactor capable of achieving both good heat dissipation and noise reduction.

  A reactor according to an aspect of the present invention includes a coil having a winding portion formed by spirally winding a winding, a magnetic core having a portion disposed in the winding portion, the coil, and the magnetic core. The metal member which has the mounting surface of the assembly containing this, and the insulating layer which is provided on the mounting surface of the said metal member, and joins the said winding part and the said metal member is provided. The insulating layer includes a resin and is composed of a plurality of insulating materials having different hardnesses, and includes a hard region composed of a hard insulating material and a soft region composed of an insulating material softer than the hard insulating material. Regions alternately exist when viewed in the axial direction of the winding portion.

The manufacturing method of the reactor which concerns on 1 aspect of this invention is equipped with the following preparatory processes, a formation process, a solidification process, and a filling process.
(Preparation step) An assembly including a coil having a winding portion formed by winding a winding in a spiral shape and a magnetic core at least partially disposed in the winding portion, and a mounting surface of the combination The process of preparing the metal member which has, and the insulating material containing resin.
(Formation process) The process of forming a non-solidified layer on the said mounting surface using the said insulating material.
(Solidification step) The wound part of the assembly is placed on the unsolidified layer so that the unsolidified layer is sequentially solidified from the area on the mounting surface side to the area on the wound part side. The step of forming a solidified layer having open pores while fixing the winding part to the mounting surface as described above.
(Filling step) The hardness after solidification is different from that of the insulating material, and the insulating material containing resin is filled in a low-viscosity state that can be filled in the open pores and then solidified, and the winding portion and the mounting surface described above And forming an insulating layer including a plurality of insulating materials having different hardnesses.

  The reactor described above can achieve both good heat dissipation and noise reduction. The reactor manufacturing method described above can manufacture a reactor that can achieve both good heat dissipation and noise reduction.

It is a schematic perspective view which shows the reactor of Embodiment 1. FIG. It is a longitudinal cross-sectional view which shows the state which cut | disconnected the reactor of Embodiment 1 by the (II)-(II) cutting line shown in FIG. 1, and shows only the bottom part side of a case. It is a plane sectional view showing the state where the reactor of Embodiment 1 was cut by the (III)-(III) cutting line shown in Drawing 1, and expands and shows only some turns among the winding parts of a coil. It is a disassembled perspective view of the union body with which the reactor of Embodiment 1 is equipped. It is process explanatory drawing explaining a part of manufacturing method of the reactor of Embodiment 1. FIG.

[Description of Embodiment of the Present Invention]
First, embodiments of the present invention will be listed and described.
(1) A reactor according to an aspect of the present invention includes a coil having a winding portion formed by spirally winding a winding, a magnetic core having a portion disposed in the winding portion, the coil, and the above A metal member having a mounting surface of a combined body including a magnetic core, and an insulating layer provided on the mounting surface of the metal member and joining the winding portion and the metal member. The insulating layer is made of a plurality of insulating materials containing resin and having different hardness. In this insulating layer, a hard region made of a hard insulating material and a soft region made of an insulating material softer than the hard insulating material are alternately present when viewed in the axial direction of the winding portion.

  Since the above reactor includes an insulating layer between the coil winding portion and the metal member, it is excellent in electrical insulation, and the insulating layer includes both a hard insulating material and a soft insulating material. Therefore, it is possible to achieve both good heat dissipation and noise reduction for the following reasons.

(Heat dissipation)
-Although the said insulating layer contains a several different material, it does not have the vertically stacked structure described in patent document 1. FIG. Specifically, for each of the insulating layer and the joining layer of the vertically stacked structure, a flat cross section cut perpendicular to the thickness direction is taken, and when this flat cross section is viewed in the axial direction of the coil winding portion, The vertically stacked joining layer has a flat cross section made of a uniform material from one end to the other end of the wound portion, but the insulating layer has alternating regions made of different materials. Has a flat cross section. Such an insulating layer can contain both a hard region and a soft region even if it has a thickness similar to the thickness of one layer constituting the joining layer of the conventional vertically stacked structure. Therefore, it is easy to reduce the average thickness of the insulating layer as compared with the vertically stacked structure, and it is easy to reduce the distance between the coil winding portion and the metal member (hereinafter sometimes referred to as a facing distance). The winding part and the metal member can be arranged close to each other. Therefore, the heat radiation path from the winding part to the metal member is shortened, and the thermal resistance can be reduced.
-Since the insulating layer includes a plurality of different materials, at least one of the insulating materials can be made to have excellent thermal conductivity by containing a ceramic filler, and the thermal conductivity of the insulating layer itself can be improved. Enhanced.

(Noise reduction)
-Since the insulating layer includes a hard region and a soft region, when the magnetic core receives vibrations from the outside or from the outside, the soft region can be deformed to absorb this vibration. Propagation can be reduced.
-Since the insulating layer includes a hard region and a soft region, when stress is applied, the soft region can be deformed and the stress can be relaxed, and the stress applied to the hard region can be reduced. When subjected to an impact, the hard region that is difficult to deform can reduce the impact on the soft region. Such vibration absorption, stress relaxation, impact reduction, and the like can reduce cracking, breakage, peeling, and the like of the insulating layer due to vibration, impact, stress, and the like, and the insulating layer can be satisfactorily maintained for a long time. From this point, it can be said that the insulating layer is excellent in durability against an external action.

  (2) As an example of the reactor described above, there is a mode in which the insulating layer includes one of the hard insulating material and the soft insulating material and includes an inclusion region surrounded by the other insulating material.

  When the inclusion region is a soft region composed of a soft insulating material, the soft region existing at an appropriate interval in the hard region can absorb the vibration of the magnetic core and the vibration from the outside and reduce the noise well. it can. These soft regions can relieve stress and reduce peeling of the insulating layer, etc., so that the fixed state between the coil winding part and the metal member can be maintained well, and this form is excellent in heat dissipation and insulation. It can be secured. When the hard region is made of an insulating material having excellent heat dissipation described later, the heat dissipation is further improved.

  Or, if the inclusion region is a hard region made of a hard insulating material, the soft core can reliably absorb the vibration of the magnetic core, absorb external vibrations, and relieve stress, thereby reducing noise. Excellent heat dissipation. In particular, this configuration has a hard region that is more rigid and difficult to deform than the soft region, and can reduce deformation and breakage of the soft region due to external impact, thereby reducing the vibration and stress relaxation effects of the soft region. Obtained well. Moreover, since this form can also maintain the fixed state of the winding part of a coil and a metal member favorably, it can also ensure insulation while being excellent in heat dissipation. In this form, the insulating layer has a relatively large number of soft regions, but has excellent durability against external effects, and can maintain desired characteristics over a long period of time.

  (3) As an example of the above-described reactor, in the case of (2) including the above-described inclusion region, the inclusion region is formed along the circumferential direction of the turns constituting the winding portion and disposed between adjacent turns. The form containing the rod-shaped body made is mentioned.

  The said form equips at least one of the adjacent areas between the adjacent turns in an insulating layer with a rod-shaped inclusion area | region. As a representative form, when the insulating layer is viewed in the axial direction of the coil winding portion, a plurality of rod-shaped inclusion regions are arranged in parallel to the axial direction, that is, between a plurality of adjacent turns. The form provided with a rod-shaped body is mentioned. In the above configuration, since there is an inclusion region between the turns, the interval in which the hard region and the soft region are alternately arranged when the insulating layer is viewed in the axial direction of the winding portion is the size of the winding forming the turn. It can be said that the hard region and the soft region are provided in a well-balanced manner from the viewpoint that the thickness can be about the thickness (thickness) and the inclusion region can exist for a long time along the turn direction. Therefore, the said form can acquire favorable effects, such as a vibration absorption and stress relaxation by a soft area | region, and the rigidity improvement by a hard area | region, and can make favorable heat dissipation and noise reduction compatible. Moreover, although the above-mentioned form has sufficient inclusion region, the thickness of the insulating layer can be about the thickness of the outer region covering the inner region, so to speak, it can be about the thickness of one layer created by the outer region. No increase in distance and excellent heat dissipation. The said form provided with the insulating layer containing a rod-shaped inclusion area | region between adjacent turns can be manufactured with the manufacturing method of the reactor of embodiment mentioned later, for example.

  (4) As an example of the reactor, in the case of (2) or (3) including the above-described inclusion region, the inclusion region in a longitudinal section obtained by cutting the insulating layer along a plane parallel to the axial direction of the winding portion In which the inner diameter is 0.1 mm or more and 2 mm or less.

  The inner diameter of the inner region is the diameter of the envelope circle of the inner region in the longitudinal section of the insulating layer. For example, if the longitudinal cross-sectional shape of the inner region is a circle, the inner diameter is the diameter of this circle.

  In the above configuration, the inclusion region and the outer region exist in a well-balanced manner, and effects such as vibration absorption and stress relaxation by the soft region and improvement of rigidity by the hard region can be obtained well, and good heat dissipation and noise reduction are achieved. And both. Moreover, since the inclusion region is not too large, the facing distance is not increased, and the above form is excellent in heat dissipation.

  (5) As an example of the above reactor, in any one of the above (2) to (4) including the above-described inclusion region, the inclusion region, the adjacent turn constituting the winding portion, and the metal member The form with which the cross-section T-shaped area | region pinched | interposed with a mounting surface is mentioned.

  The cross-sectional T-shaped region has a cross-sectional area compared to other regions, specifically, a region sandwiched between the surface facing the metal member placement surface and the metal member placement surface in the winding portion. Tend to be large. Since both the hard region and the soft region exist in such a relatively large region, the above-described improvement in rigidity, vibration absorption, stress relaxation, etc., compared with the case where only one of them exists. It is easy to obtain the effect.

  (6) As an example of the reactor, the metal member is a case for housing the combination, and the case is filled with an insulating material constituting the inclusion region, so that at least a part of the combination is embedded. The form which is sealing resin to perform is mentioned.

  Since the said form is provided with metal cases, it is further excellent in heat dissipation, and also it is excellent in manufacturability for the following reasons.

  In the above embodiment, since a part of the insulating layer is made of the sealing resin, it can be said that the sealing resin continuously exists inside and outside the insulating layer. In such a form, a solidified layer (outer region) having open pores is first formed of an insulating material that forms the other part of the insulating layer, and the resin material that is the raw material of the sealing resin is filled in the case and solidified. It can manufacture by doing (refer also to the manufacturing method of the reactor of the below-mentioned embodiment). When the case is filled with the resin material, the open pores are automatically filled with the resin material, and in this state, the resin material is solidified to produce an insulating layer having an inclusion region made of a sealing resin. Therefore, although the said form is provided with the insulating layer containing a several different material, it can manufacture easily while being able to reduce the number of processes by combining formation of a part of insulating layer and filling and solidification of sealing resin. .

  (7) As an example of the above reactor, there is a form in which the Shore D hardness of the hard insulating material is 50 or more and the Shore A hardness of the soft insulating material is 80 or less.

  The above configuration is made of an insulating material with a hard region that is sufficiently hard and excellent in rigidity, and a soft region is formed with an insulating material that is sufficiently soft and excellent in flexibility, so that the above-described improvement in rigidity, vibration absorption, and stress relaxation are achieved. It is easy to obtain such effects.

  (8) As an example of the above-described reactor, the thermal conductivity of the hard insulating material is 2.0 W / m · K or more and the thermal conductivity of the soft insulating material is 0.1 W / m · K or more and 5.0 W. The form which satisfy | fills at least one of below / m * K is mentioned. The measurement of thermal conductivity is performed by cutting out a test piece from the insulating layer or analyzing a component of the insulating material constituting the insulating layer and producing a test piece based on the analysis result.

  In the case of having a hard region made of an insulating material having a high thermal conductivity that satisfies the above specific range, the heat dissipation is further improved. As the insulating material having high thermal conductivity, for example, a material containing a resin and a filler made of an insulating material such as ceramics having excellent thermal conductivity can be used (this also applies to a soft insulating material described later). .

  When the soft insulating material has a particularly high thermal conductivity, for example, when the soft insulating material has a soft region composed of a high thermal conductive insulating material having a thermal conductivity of 1 W / m · K or more, the heat dissipation performance is improved. Even better. On the other hand, the said form which has a soft area | region comprised from an insulating material with comparatively low heat conductivity whose heat conductivity is less than 1 W / m * K is easy to form an insulating layer for the following reasons, and is excellent in manufacturability. As the raw material for the soft region, a material that is substantially free of the filler and that is made of a resin, or a material that contains the filler and has a low content can be used. Such an insulating material is generally low in an unsolidified state. This is because it is a viscosity and it is easy to perform operations such as coating and filling.

  In addition, in the above embodiment, when one insulating material satisfies the above specific range, various other insulating materials can be used, and the degree of freedom in material selection is high.

  (9) As an example of the reactor, a mode in which the withstand voltage of the insulating layer is 1 kV / mm or more can be given.

  The said form has a high withstand voltage, and is excellent in the electrical insulation between a coil and a metal member.

(10) The manufacturing method of the reactor which concerns on 1 aspect of this invention is equipped with the following preparatory processes, a formation process, a solidification process, and a filling process.
(Preparation step) An assembly including a coil having a winding portion formed by spirally winding a winding, and a magnetic core disposed at least in part in the winding portion, and a mounting surface of the combination The process of preparing the metal member which has, and the insulating material containing resin.
(Formation process) The process of forming an unsolidified layer on the said mounting surface using the said insulating material.
(Solidification step) The winding part of the assembly is placed on the unsolidified layer so that the unsolidified layer is solidified sequentially from the region on the placement surface side to the region on the winding part side. The step of forming a solidified layer having open pores while fixing the winding part to the placement surface described above.
(Filling step) The hardness after solidification is different from that of the insulating material, and the insulating material containing resin is filled in a low-viscosity state that can be filled in the open pores and then solidified, and the winding portion and the placement surface described above And forming an insulating layer including a plurality of insulating materials having different hardnesses.

  The inventors of the present invention manufactured an insulating layer interposed between a coil winding portion and a metal member under various conditions, and firmly fixed the winding portion to the metal member, from the winding portion to the metal member. We studied a configuration that can efficiently conduct heat conduction and reduce noise. As a result, an unsolidified layer made of an insulating material containing a resin is formed on the metal member, and the unsolidified layer is heated so that the unsolidified layer is solidified from the metal member side toward the winding portion side. It was found that when controlled, open pores can be formed in the solidified layer. Open pores could be formed even with an extremely thin layer having an average thickness of 1 mm or less. The formation mechanism of open pores is not clear, but is considered as follows.

  When an unsolidified layer is formed on a metal member and a combined body including a coil and a magnetic core is disposed on the unsolidified layer, the unsolidified layer can be said to be sandwiched between the combined body and the metal member. . Thus, the unsolidified layer sandwiched by inserting the assembly of the unionized layer and the metal member into, for example, a heating furnace or placing a heating source in the vicinity of the metal member. Heat. Then, since the heat capacity of the assembly is usually sufficiently larger than that of the metal member, the unsolidified layer is easily heated from the metal member side to the winding portion side in the thickness direction, and the metal in the unsolidified layer The region on the member side is easily maintained at the solidification temperature and is easily solidified. The region on the winding part side in the unsolidified layer is deheated by the assembly and is not easily heated as compared with the region on the metal member side, and solidifies behind the region on the mounting surface side of the metal member. . If the viscosity of the insulating material is lowered to some extent by heating before the region on the winding portion side in the unsolidified layer reaches the solidification temperature, the insulating material can enter between adjacent turns by capillary action. By the movement of the insulating material between the turns and the sequential solidification of the region on the metal member side, the insulating material between the winding portion and the metal member in the unsolidified layer is gradually depleted. Therefore, it is considered that, instead of the insulating material, the atmospheric gas around the assembly is sucked from the side surface of the unsolidified layer or the like, and as a result, open pores are formed on the side surface of the solidified layer. In addition, as described above, the insulating material flows between adjacent turns, so that a cylindrical shape along the circumferential direction of the turns is formed in a T-shaped region sandwiched between the adjacent turns and the mounting surface of the metal member. It is considered that the open pores are formed.

  In the above-described reactor manufacturing method, an open pore is formed at the same time as the unsolidified layer is solidified, and the open pore is filled with an insulating material whose viscosity is adjusted, so that a hard portion is formed between the coiled portion and the metal member. It is possible to manufacture a reactor including an insulating layer including a hard region composed of a simple insulating material and a soft region composed of a soft insulating material. That is, the reactor manufacturing method described above can manufacture the reactor according to the above-described embodiment, which is excellent in insulation and can achieve both good heat dissipation and noise reduction.

Moreover, the manufacturing method of said reactor can manufacture a reactor provided with the insulating layer of said specific structure with sufficient productivity for the following reasons.
-Open pores can be formed automatically even if the solidified layer is an extremely thin layer having an average thickness of 1 mm or less.
・ If a soft insulating material that does not contain the above-mentioned filler and is made of a resin or a material that contains a small amount of filler has low viscosity in an unsolidified state, it is easy to form an unsolidified layer or open it. It may be easy to fill the pores.

  In particular, the metal member is a metal case for housing the assembly, a reactor including the case and a sealing resin filled in the case, and an insulating material filling the open pores is a sealing resin. In some cases, the productivity is excellent for the following reasons. In the case of manufacturing a reactor including the above-described vertically stacked bonding layer and the sealing resin, a process of filling and solidifying the sealing resin is further performed as described above, and the formation and solidification of the unsolidified layer is repeated a plurality of times. On the other hand, in the above-described reactor manufacturing method, the formation and solidification of the unsolidified layer may be performed once, and the reactor including the insulating layer having the specific structure described above is manufactured in the process of filling and solidifying the sealing resin thereafter. This is because the number of steps is smaller than in the case of the vertically stacked structure. Furthermore, since the insulating layer having the above specific structure is excellent in heat dissipation, the content of filler is small as a sealing resin, and when an insulating material having a low viscosity in an unsolidified state is used, This is because it is easy to fill the case, and the filling time can be shortened.

  (11) As an example of the manufacturing method of the reactor, in the solidification step, the temperature difference is set so that the temperature of the region on the metal member side in the unsolidified layer is higher than the temperature of the region on the winding part side. The form which provides and forms the said solidified layer is mentioned.

  In the above configuration, since the region on the metal member side in the unsolidified layer is set to a temperature higher than that of the wound portion side, the unsolidified layer is easily solidified from the metal member side toward the wound portion side. The pores can be formed sufficiently and reliably. As a result, the above-described embodiment makes it easy to manufacture a reactor including an insulating layer in which the open pores of the solidified layer are filled with an insulating material having a hardness different from that of the solidified layer.

[Details of the embodiment of the present invention]
Embodiments of the present invention will be specifically described below with reference to the drawings. The same reference numerals in the figure indicate the same names.

[Embodiment 1]
First, the reactor 1 of Embodiment 1 is demonstrated with reference to FIGS. 1-4, and the manufacturing method of the reactor of Embodiment 1 is demonstrated for every process mainly with reference mainly to FIG. 1 to 3 and 5, the insulating layer 6, the unsolidified layer 610, the thickness t ₆₀₀ of the solidified layer 600, the size of the open pores 6 p (the inner diameter D, the rod length L described later), and the like are adjacent to each other. An interval (in particular, FIG. 3) between the turns 2t and 2t is exaggerated or schematically shown for easy understanding.

(Reactor)
-Overall structure The reactor 1 of Embodiment 1 is arrange | positioned in the coil 2 which has the winding parts 2a and 2b formed by helically winding the coil | winding 2w, and the winding parts 2a and 2b, as shown in FIG. A magnetic member 3 having a portion to be mounted, a metal member having a mounting surface on which the combined body 10 including the coil 2 and the magnetic core 3 is mounted, and a coil 2 provided on the mounting surface of the metal member. And an insulating layer 6 for joining the metal member. The reactor 1 in FIG. 1 is made of a metal case 4 that houses a combination 10 and the case 4 is filled with at least a part of the combination 10 (here, substantially all except for the end of the winding 2w). ) Is embedded, and an example provided with sealing resin 100 is shown. The metal member in this example is the case 4, and the mounting surface is a part of the inner bottom surface 40 i of the bottom portion 40 of the case 4. Reactor 1 is used with case 4 attached to an installation target (not shown) such as a converter case. When the installation target has a cooling structure (not shown), the reactor 1 is cooled by the installation target. In particular, the heat of the winding portions 2 a and 2 b of the coil 2 and the heat of the magnetic core 3 are transmitted to the bottom portion 40 through the insulating layer 6 and are transmitted to the installation target outside the case 4 through the bottom portion 40.

  In the reactor 1 of the first embodiment, the insulating layer 6 includes a resin and is made of a plurality of insulating materials having different hardness, and the insulating layer 6 is wound around the winding portions 2a and 2b as shown in the broken-line circle in FIG. When viewed in the axial direction (the left-right direction in FIG. 2), a region composed of an insulating material having a hardness higher or lower than that of the insulating material is intermittent with respect to a region composed of an insulating material having a certain hardness. One of the features is a point that exists in a line. In FIG. 2, as the insulating layer 6, one region is composed of one of a hard insulating material and a soft insulating material, and is an outer region 60 surrounding the other insulating material, and the other region is a constituent material of the outer region 60. An example is shown in which the encapsulating region 61 is surrounded by and the constituent material of the encapsulating region 61 is the sealing resin 100. Hereinafter, the outline of the case 2, which is an example of the coil 2, the magnetic core 3, and the metal member, which are the main members of the reactor 1 of the first embodiment, and the details of the insulating layer 6 and the sealing resin 100 that are characteristic points will be described first. Next, a method for manufacturing the reactor according to the first embodiment capable of manufacturing the reactor 1 will be described. After that, details and modifications of the main members of the reactor 1 and other components will be described.

Coil The coil 2 includes a pair of cylindrical winding portions 2a and 2b formed by spirally winding one continuous winding 2w as shown in FIG. 4 and a part of the winding 2w. And a connecting portion 2r that is formed and connects both winding portions 2a and 2b. Each winding part 2a, 2b is arrange | positioned in parallel (side by side) so that a mutual axis | shaft may be parallel. The winding 2w in this example is a covered rectangular wire (so-called enameled wire) including a rectangular conductor (copper or the like) having a rectangular cross section and an insulating coating (polyamideimide or the like) covering the outer periphery of the conductor. . Each winding part 2a, 2b shown in FIG. 4 is a square cylindrical edgewise coil with rounded corners. The outer shapes of the winding portions 2a and 2b are each composed of four planes and a curved surface connecting adjacent planes, and one of the four planes is a mounting surface of the metal member (in this case, the inside of the case 4). The bottom surface 40i is disposed opposite to the bottom surface 40i (hereinafter the same as in the first embodiment).

  Both end portions of the winding 2w are drawn out from the winding portions 2a and 2b in an appropriate direction, the insulating coating at the tip thereof is peeled off, and a terminal fitting (not shown) is connected to the conductor. The coil 2 is electrically connected to an external device (not shown) such as a power source via the terminal fitting.

Magnetic Core The magnetic core 3 includes a plurality of columnar core pieces 31m and 32m and a plurality of gap members 31g typically interposed between the core pieces 31m and 31m as shown in FIG. Assembled. In this example, core pieces 32m and 32m that are U-shaped when viewed from above in FIG. 4 are arranged so that the U-shaped openings face each other. Between these core pieces 32m and 32m, a pair of laminated body which laminated | stacked the core piece 31m and the gap material 31g is arrange | positioned side by side (parallel). With this arrangement, the magnetic core 3 is assembled in an annular shape, and forms a closed magnetic path when the coil 2 is excited. The core piece 31m and the gap material 31g in the magnetic core 3 and a part of the U-shaped core piece 32m (protruding portions described later) are arranged in the winding portions 2a and 2b of the coil 2 as shown in FIG. The remaining portion (a block described later) of the U-shaped core piece 32m constitutes a portion protruding from the coil 2 without the winding portions 2a and 2b being disposed.

  The core pieces 31m and 32m are mainly composed of a soft magnetic material. The core pieces 31m and 32m are formed by compacting a soft magnetic metal powder such as iron or an iron alloy (Fe-Si alloy, Fe-Ni alloy, etc.) or a coating powder further provided with an insulation coating, a soft magnetic powder, A composite material containing resin can be used. In this example, the green compact is used. The gap material 31g is typically made of a material having a relative permeability smaller than that of the core pieces 31m and 32m, for example, a nonmagnetic material such as alumina.

-Metal member The reactor 1 is equipped with the metal case 4 which can accommodate the combination body 10 as a metal member in which the combination body 10 is mounted. The case 4 has functions such as mechanical protection of the assembly 10 and protection from the external environment (protection from corrosive gas, etc.), and is generally made of metal so that it is generally more heat-resistant than resin. Since it is excellent in conductivity, it also functions as a heat dissipation path from the combined body 10 to the installation target. The case 4 is also a member that is directly attached to the installation target.

  Such a case 4 typically includes a bottom portion 40 having an inner bottom surface 40i in which a mounting area of the assembly 10 is provided, and a side wall portion 41 that stands from the bottom portion 40 and surrounds the periphery of the assembly 10. And a box having an opening on the side facing the bottom 40 (upper side in FIG. 1). The case 4 in this example is a metal box in which a bottom portion 40 and a side wall portion 41 are integrally formed. In FIG. 1, a case 4 having a rectangular flat plate-shaped bottom portion 40 and a rectangular frame-shaped side wall portion 41 is shown.

  Of the inner bottom surface 40i, if at least the mounting region of the combined body 10 is a flat plane as shown in FIG. 2, one surface of the winding portions 2a and 2b of the coil 2 (the surface facing the inner bottom surface 40i, FIG. Then, the lower surface) can be arranged parallel to the inner bottom surface 40i. In this case, a region close to the inner bottom surface 40i on the one surface (lower surface) of the winding portions 2a and 2b can be provided sufficiently wide, so that the mounting of the combined body 10 can be stabilized and good heat dissipation can be achieved. . Moreover, if the mounting area | region of the assembly 10 in the inner bottom face 40i is a flat plane, the formation operation of the insulating layer 6 and the mounting operation of the assembly 10 will be easy, and it is excellent in the manufacturability of the reactor 1.

  Examples of the constituent material of the metal case 4 include aluminum and its alloys, magnesium and its alloys, copper and its alloys, silver and its alloys, iron and austenitic stainless steel. When formed of aluminum, magnesium, or an alloy thereof, the case 4 can be lightened. In particular, aluminum or aluminum alloy is preferable because it has a high thermal conductivity and is excellent in the case 4 having excellent thermal conductivity to the installation target. Furthermore, the integrally formed metal case 4 is excellent in rigidity and strength, and the strength of the reactor 1 as a whole can be increased.

Insulating layer The insulating layer 6 will be described mainly with reference to FIG. FIG. 2 is a longitudinal sectional view of the reactor 1 cut along a plane parallel to the axial direction of the winding portion 2 a of the coil 2, and shows the insulating layer 6 and the vicinity thereof. In the broken line circle of FIG. 2, the intervening region between the winding part 2 a and the bottom part 40 of the case 4 is shown enlarged.

  In the reactor 1, an insulating layer 6 made of an insulating material is interposed between the winding portions 2 a and 2 b of the coil 2 and the bottom portion 40 of the case 4. The insulating layer 6 in this example is also interposed between a portion of the magnetic core 3 protruding from the coil 2 (a part of the core piece 32 m) and the bottom 40 of the case 4. The insulating layer 6 joins the winding portions 2 a and 2 b and the core piece 32 m of the magnetic core 3 and the bottom portion 40.

  In the reactor 1 of the first embodiment, the insulating layer 6 is composed of different insulating materials, particularly a plurality of insulating materials having different hardnesses, and includes a plurality of regions having different hardnesses. Specifically, the insulating layer 6 includes a hard region (for example, the outer region 60) that includes a resin and is configured of a hard insulating material, and a soft region that includes a resin and is configured of an insulating material that is softer than the hard insulating material. A region (for example, an inclusion region 61). As shown in the broken-line circle in FIG. 2, when the insulating layer 6 is viewed in the axial direction of the winding portions 2a and 2b, hard regions and soft regions exist alternately.

.. Insulating characteristics The insulating layer 6 is preferably as high as possible withstand voltage in order to insulate between the winding portions 2a and 2b of the coil 2 and the bottom 40 of the case 4. Specifically, the withstand voltage of the insulating layer 6 is preferably 1 kV / mm or more, more preferably 3 kV / mm or more, 5 kV / mm or more, or 7 kV / mm or more. When the insulating layer 6 includes a material having excellent electrical insulation, for example, a filler made of ceramics described later, the withstand voltage tends to be increased as the content increases.

· The average thickness of the insulating layer 6 thickness t _{6 (see} the broken line circle in FIG. 2) is wound portion 2a of the coil 2, the surface facing the bottom 40 in 2b (in Figure 2 the lower surface) and the casing 4 It is equal to the facing distance from the inner bottom surface 40i, and it is preferable that the thickness is thin for the purpose of efficiently conducting heat conduction from the winding portions 2a, 2b of the coil 2 to the bottom portion 40 of the case 4. Although the insulating layer 6 is composed of a plurality of different insulating materials, the average thickness t ₆ is different from that of the above-described joining layer having the vertically stacked structure, and the average thickness t ₆ is the thickness of a single layer made of one insulating material (FIG. 2). In this case, the thickness is substantially equal to the thickness of the outer region 60, and tends to be thinner than the above-described joining layer having the vertically stacked structure. For example, the average thickness _{t 6} of the insulating layer 6, 2 mm or less, more 1mm or less, 0.8 mm or less, 0.5 mm or less, and a 0.1 mm (100 [mu] m) or less. Insulating layer 6 average thickness _{t 6} is too thin for (if the opposing distance is too small), since it leads to a decrease in insulation between the winding part 2a, 2b and the bottom 40, 30 [mu] m (0.03 mm ) And more preferably 50 μm or more and 70 μm or more. The thickness t ₆₁₀ of the unsolidified layer 610 average thickness t ₆ of the insulating layer 6 during the manufacturing process so as to satisfy the range described above _(FIG. 5, described later), the pressing force of the combined product 10, may like to adjust the solidification conditions .

The average thickness t ₆ of the insulating layer 6 is a longitudinal section of the insulating layer 6, and the mounting surface of the metal member in the winding portions 2 a and 2 b of the coil 2 (inner bottom surface 40 i of the case 4) of the insulating layer 6. The thickness of the region existing between the facing surface and the placement surface is measured at a plurality of points (for example, n ≧ 3), and the average is obtained.

Of the plurality of turns 2t constituting the winding portions 2a and 2b of the coil 2, a part of the constituent material of the insulating layer 6 is filled between the adjacent turns 2t and 2t, and at least a part of the turn 2t. May be embedded in the constituent materials. In the broken-line circle in FIG. 2, a state in which the constituent material is filled in a region near the bottom 40 of the case 4 between the turns 2 t and 2 t is illustrated. When at least a part of the turn 2t is embedded in the insulating layer 6, the contact area between the winding portions 2a and 2b and the insulating layer 6 can be increased, and the insulating layer 6 allows the coil 2 and the metal member (here, the case 4). The bottom portion 40. Hereinafter, the same as in the first embodiment can be firmly fixed. The average measurement of the thickness t ₆ of the insulating layer 6 above is performed except for the filled portion between adjacent turns 2t, 2t.

.. Constituent material Both the hard insulating material and the soft insulating material constituting the insulating layer 6 contain a resin. Resin is generally an electrically insulating material and can be suitably used as a constituent material of the insulating layer 6. In addition, some resins have a certain degree of adhesiveness when not solidified, and the coil 2 and the metal member (the bottom 40 of the case 4) can be fixed after solidification. If it is resin containing an adhesive, stronger fixation can be expected. The adhesive mainly includes a thermosetting resin such as an epoxy resin, a silicone resin, or a urethane resin. In addition, it is preferable that the resin has heat resistance to such an extent that the resin is not excessively softened with respect to the highest temperature achieved when the reactor 1 is used.

... Hard insulating material .... Component Hard insulating material has a certain degree of hardness after solidification among various resins such as thermosetting resin, thermoplastic resin, moisture curable resin, and room temperature curable resin. High resin is mentioned. Specific hardness will be described later. Alternatively, the hard insulating material includes a resin having an arbitrary hardness and a hard powder having excellent electrical insulation and higher hardness than the resin. This insulating layer 6 can be provided with a hard region having a sufficiently high hardness by a hard powder irrespective of the hardness of the resin.

  Examples of the thermosetting resin include an epoxy resin, a urethane resin, and an unsaturated polyester. Examples of the thermoplastic resin include polytetrafluoroethylene (PTFE) resin, liquid crystal polymer (LCP), polyamide (PA) resin such as nylon 6 and nylon 66, polyamideimide resin, and polyimide resin.

  The hard powder is made of a non-metallic inorganic material typified by ceramics such as oxides such as alumina, silica and magnesium oxide, nitrides such as silicon nitride, aluminum nitride and boron nitride, and carbides such as silicon carbide. Can be mentioned. Ceramics are generally harder than resins, have excellent electrical insulation properties, and have excellent thermal conductivity. Hard powders made of ceramics (hereinafter sometimes referred to as ceramic fillers) are added with hard insulating materials. Suitable for the agent. Either a form containing a single kind of hard powder or a form containing a plurality of kinds of hard powder can be used.

.... Hardness Specific hardness of the hard insulating material is 50 or more in Shore D hardness. The higher the hardness of the hard insulating material, the higher the hardness of the hard region, and the higher the rigidity of the insulating layer 6. The insulating layer 6 should be resistant to vibration and impact from the outside, and excellent in vibration resistance and impact resistance. Can do. Considering impact resistance and the like, the Shore D hardness of the hard insulating material is preferably 60 or more, more preferably 70 or more, and 80 or more. In the case of using a material that is substantially composed only of a resin as a hard insulating material, a resin satisfying a Shore D hardness of 50 or more may be used. Or it is good to adjust the material, content, etc. of the above-mentioned hard powder so that Shore D hardness may satisfy 50 or more.

.... Thermal conductivity When a hard insulating material is substantially composed of resin, its thermal conductivity is typically about 0.1 W / m · K or more and about 0.5 W / m · K or less. And less than 1.0 W / m · K. When the above ceramic filler is included, the thermal conductivity of the hard insulating material becomes higher and satisfies, for example, 1 W / m · K or more. Depending on the material and content of the ceramic filler, the thermal conductivity of the hard insulating material is 1.5 W / m · K or more, further 2.0 W / m · K or more, 3.0 W / m · K or more. It can satisfy 0 W / m · K or more. This thermal conductivity tends to be higher as the content of the ceramic filler is higher. However, when the content is too high, the viscosity of the mixture of raw materials is increased and it is difficult to form a hard region. Therefore, in consideration of manufacturability, it is considered that a material having a thermal conductivity of about 10 W / m · K or less can be easily used as a hard insulating material.

・ ・ ・ Soft insulating materials ・ ・ ・ ・ Components Soft insulating materials have the above-mentioned hardness after solidification among various resins such as thermosetting resins, thermoplastic resins, moisture curable resins, and room temperature curable resins. The resin is lower than that of the hard insulating material. Specific hardness will be described later. Alternatively, the soft insulating material may include a resin and the above-described hard powder within a range where the hardness is lower than that of the above-described hard insulating material, and preferably within a range that satisfies the hardness described below. By containing the ceramic filler described above, heat dissipation can be improved. Specific examples of the resin and specific examples of the hard powder are as described above.

.... Hardness Specific hardness of the soft insulating material includes Shore D hardness of less than 50. Further, the hardness of the soft insulating material may be 80 or less in Shore A hardness. The lower the hardness of the soft insulating material or the greater the difference in hardness from the hard insulating material, the lower the hardness of the soft region and the higher the flexibility of the soft region. Therefore, it can be set as the insulating layer 6 which is easy to absorb the vibration of the magnetic core 3, the absorption of the vibration from the outside, and stress relaxation. In consideration of flexibility and the like, the Shore A hardness of the soft insulating material is preferably 70 or less, and more preferably 60 or less. If the soft insulating material is too soft, it is easy to crack or break when subjected to an impact from the outside, and is inferior in impact resistance. Therefore, the Shore A hardness of the soft insulating material is 30 or more, and further 40 or more. preferable. Examples of the resin having a Shore A hardness of 80 or less include a silicone resin, a soft epoxy resin, and a soft urethane resin. When the above hard powder is contained, the material, content, etc. of the hard powder may be adjusted so that the Shore A hardness satisfies 80 or less. Either a form containing a single kind of hard powder or a form containing a plurality of kinds of hard powder can be used.

.... Thermal conductivity When a soft insulating material is substantially composed only of a resin, its thermal conductivity is typically about 0.1 W / m · K or more and about 0.5 W / m · K or less. And less than 1.0 W / m · K. When the above ceramic filler is included, the thermal conductivity of the soft insulating material can satisfy 1.0 W / m · K or more, and further 1.5 W / m · K or more depending on the material and content. . The thermal conductivity of the soft insulating material also tends to increase as the ceramic filler content increases, but the hardness of the soft region after solidification becomes too high, and the Shore A hardness can exceed 80. Considering the hardness in the soft region, it is considered that the thermal conductivity of the soft insulating material is preferably 5.0 W / m · K or less, more preferably 3.0 W / m · K or less, and less than 2.0 W / m · K. .

... Heat conductivity of hard insulation materials and soft insulation materials Thermal conductivity of hard insulation materials is 2.0 W / m · K or more, and heat conductivity of soft insulation materials is 1.0 W / m · If at least one of K or more is satisfied, the heat dissipation is excellent, and if both are satisfied, the insulating layer 6 can be further improved in heat dissipation. If at least one of the thermal conductivity of the hard insulating material is 2.0 W / m · K or more and the thermal conductivity of the soft insulating material is less than 1.0 W / m · K, the hard region with high thermal conductivity There are at least one of the effects that excellent heat dissipation can be obtained and that, when the soft insulating material is in an unsolidified state, the viscosity tends to be low and a soft region is easily formed.

... Existence state of hard region and soft region Of insulating layer 6, a region sandwiched between winding parts 2a, 2b of coil 2 and a placement surface of metal member (inner bottom surface 40i of case 4) When viewed in the axial direction of 2a and 2b, as shown in the broken-line circle in FIG. 2, the hard region and the soft region are alternately present over the entire region. FIG. 2 shows an example in which a plurality of inclusion regions 61 are arranged in parallel within the outer region 60 at a predetermined interval. The outer region 60 is a hard region, the inner region 61 is a soft region, or the outer region 60 is a soft region. Region 61 is a hard region. Specifically, the inner region 61 has a circular shape in a longitudinal section, an inner diameter D of 0.1 mm or more and 2 mm or less, and the adjacent turns 2t and 2t constituting the winding portion 2a (2b) and the mounting of the metal member. It is provided in a region Ta having a T-shaped cross section sandwiched between the placement surface (the inner bottom surface 40i of the case 4). Furthermore, the inclusion region 61 of the insulating layer 6 in this example is formed along the circumferential direction of the turn 2t that constitutes the winding portions 2a and 2b, and is a rod-like body disposed between the adjacent turns 2t and 2t, for example, Includes round bars.

3, the reactor 1 shown in FIG. 1, an insulating layer 6 about half position of the average thickness t ₆ (winding part 2a, the mounting surface of the 2b and the metal member (the inner bottom surface 4i of the case 4) Is a cross-sectional view taken along a plane orthogonal to the thickness direction of the insulating layer 6 at a position that is about half of the facing distance between each of the turns 2a and 2b of the plurality of turns 2t. Only the turn 2t group is shown. As shown in FIG. 3, when attention is paid to one winding portion 2a, rod-shaped inclusion regions 61 are arranged in parallel between adjacent turns 2t and 2t. When attention is paid to the other winding part 2b, similarly, rod-shaped inclusion regions 61 are arranged in parallel between adjacent turns 2t and 2t. When attention is paid to a region sandwiched between adjacent turns 2t, 2t in the plane cross section of FIG. 3, a rod-shaped inclusion region 61 exists along the circumferential direction of the turn 2t at the approximate center of this region. The outer regions 60 and 60 are present on both sides of the outer region so as to sandwich the region. 3 is viewed in the direction in which the winding portions 2a and 2b are arranged in parallel (the vertical direction in FIG. 3), one winding portion 2a passes between both winding portions 2a and 2b and the other winding. The sealing resin 100 exists continuously toward the portion 2 b, and the insulating material interposed between the adjacent turns 2 t and 2 t in the sealing resin 100 forms the inclusion region 61. In addition, since both winding part 2a, 2b is a square cylinder shape which rounded the corner | angular part, comparatively much sealing resin 100 exists between both winding part 2a, 2b.

  The reactor 1 including the insulating layer 6 including the plurality of rod-shaped inclusion regions 61 and the outer region 60 that holds the rod-like inclusion regions 61 in a parallel state is, for example, a reactor manufactured according to the first embodiment described later. It can be manufactured using the method.

The existence state of the hard region and the soft region can be changed as appropriate.
The inner region 61 shown in FIG. 2 can be said to be a region that does not contact both the winding portions 2a and 2b of the coil 2 and the metal member (the bottom 40 of the case 4), and the outer region 60 is a region that contacts both. Therefore, for example, if the inclusion region 61 is a soft region, the soft region does not contact both the coil 2 and the metal member, and if the outer region 60 is a soft region, the soft region is the coil 2 and the metal member. It can be set as the form which touches both.

  Further, in the example shown in FIG. 2, a part of the outer region 60 and the inner region 61 are provided in the region Ta having a T-shaped cross section, and only the other part of the outer region 60 exists in the other regions. Therefore, for example, if the outer region 60 is a soft region, it can be configured to include a portion where only the soft region exists in a section sandwiched between the coil 2 and the metal member (the bottom portion 40 of the case 4). If the outer region 60 is a hard region, on the contrary, it can be configured to include a portion where only the hard region exists.

.... Inclusion region When the inclusion region 61 is provided, the number of the inclusion region 61 may be one, but if it is a plurality, the insulating layer 6 preferably has a large number such as the number of turns such as (turn number -1). The occupying ratio of the inclusion region 61 can be increased. As a result, the effects of both the hard region which is one of the outer region 60 and the inclusion region 61 and the soft region which is the other can be provided in a balanced manner.

  Focusing on the shape of the inclusion region 61, for example, the vertical cross-sectional shape or the end surface shape (opening shape) that can be seen on the side surface of the insulating layer 6 is a circular shape, a curved surface shape such as an elliptical shape, a triangular shape, a rectangular shape, etc. A planar shape represented by a polygonal shape such as The rod-shaped inclusion region 61 can be a non-cylindrical shape such as a polygonal column in addition to a round bar.

  When attention is paid to the size of the inclusion region 61, the diameter of the envelope circle of each inclusion region 61 in the longitudinal section of the insulating layer 6 cut along a plane parallel to the axial direction of the winding portions 2 a and 2 b of the coil 2 is determined for each inclusion region. When the inner diameter D is 61, the inner diameter D may be about ½ or less of the thickness of the winding 2w (or the diameter in the case of a round wire). Further, the inner diameter D is larger than the interval between the adjacent turns 2t and 2t, and is small enough to be accommodated in the region Ta having a T-shaped cross section. As the inner envelope diameter D is larger, the occupation ratio of the inner region 61 in the insulating layer 6 is increased, and the effects produced by both the hard region and the soft region can be provided in a balanced manner as described above. Although depending on the thickness of the winding 2w, the inner diameter D is, for example, 0.1 mm or more, and further 0.3 mm or more. Since it will be difficult to form the insulating layer 6 if the inner diameter D is too large, it is preferably 2 mm or less, more preferably 1.5 mm or less, and 1 mm or less.

The length along the circumferential direction of the turn 2t in the rod-shaped inclusion region 61 (hereinafter referred to as the rod length L, FIG. 3) is the length along the side-by-side direction (parallel direction) of the winding portions 2a and 2b ( Hereinafter, the equivalent or less than the width W _t (refer to FIG. 4) of the winding portion may be mentioned. In Figure 3, it shows the case Bocho L is equal to the width W of the portion excluding the rounded corners from the width W _t of the winding portion (FIG. 4). As the rod length L is larger, the occupation ratio of the inclusion region 61 in the insulating layer 6 is increased, and the effects produced by both the hard region and the soft region can be provided in a balanced manner as described above. Therefore, Bocho, L is 1/5 or more the width _{W t} of the winding portion, and further not less than 1/4, 1/3 or more, 1/2 or more. If the rod length L is too long, it will be difficult to form the insulating layer 6. Therefore, it is considered to be preferably equal to or less than the width W _t of the wound portion, and more preferably about 4/5 or less.

  When using the reactor manufacturing method according to the first embodiment described later, it is considered difficult to control the shape and size (the inner diameter D, the rod length L, etc.) of the inner envelope region 61 with high accuracy. However, when forming an open hole of an appropriate shape and size in a solidified layer formed of a hard insulating material or a soft insulating material using a cutting tool such as a drill, the desired shape and size It is expected that the inclusion region 61 can be formed with high accuracy.

  In addition, the inner region 61 is provided or the inner region 61 is not provided, and both the hard region and the soft region are provided on at least one of the winding portions 2a and 2b of the coil 2 and the metal member (the bottom portion 40 of the case 4). It can be set as the form which contacts. In this form, in addition to the inclusion region 61 opening on the side surface of the insulating layer 6 or not opening on the side surface, it opens to at least one of the metal member and the turn 2t and is hard or soft. This is a state including a region filled with an insulating material. Such a region may be formed when the reactor manufacturing method according to the first embodiment described later is used.

Sealing Resin In the reactor 1 shown in FIG. 1, the combined body 10 housed in the case 4 is a sealed case in which the case 4 is substantially entirely filled except for the end of the winding 2 w of the coil 2. It is embedded in the stop resin 100. Therefore, the sealing resin 100 is continuously present from the inner bottom surface 40 i of the case 4 toward the opening of the case 4. The sealing resin 100 is made of an insulating material containing resin. Therefore, the reactor 1 can prevent mechanical contact of the union 10 with the sealing resin 100 and prevent the contact between the substantially entire union 10 and the atmosphere of the external environment and has excellent corrosion resistance. The effect of preventing contact with external parts and excellent electrical insulation is obtained.

  In this example, a part of the sealing resin 100 is used as a constituent material of the insulating layer 6. 2 and 3 show an example in which the inclusion region 61 of the insulating layer 6 is made of the sealing resin 100. When a part of the sealing resin 100 constitutes a part of the insulating layer 6, the above-mentioned hard insulating material or soft insulating material can be used as the constituent material of the sealing resin 100. Specific components are as described above. In this case, the sealing resin 100 is continuously present inside and outside the insulating layer 6. Therefore, in addition to the integration of the coil 2 and the case 4 via the insulating layer 6, the integration of the coil 2 and the magnetic core 3 (particularly the core piece 32m) and the case 4 via the sealing resin 100, the insulating layer 6 and the sealing resin 100 are integrated, and the coil 2, the magnetic core 3, and the case 4 can be firmly integrated with the insulating layer 6 and the sealing resin 100.

  The sealing resin 100 should just embed at least one part of the assembly 10, and the embedding area | region of the sealing resin 100 with respect to the assembly 10 can be selected suitably. As shown in FIG. 1, when substantially the entire assembly 10 is embedded with the sealing resin 100, as described above, protection from the external environment, mechanical protection, and electrical insulation can be favorably achieved. Only a part of the combined body 10, for example, only the vicinity of the bottom 40 of the case 4 can be embedded. This form can reduce the amount of the sealing resin 100 used, shorten the filling time / solidification time, and is excellent in manufacturability. Further, the depth (height) of the case 4 can be reduced, so that a small case can be used and the weight can be reduced. Even when the amount of the sealing resin 100 is small, the reactor 1 can have a good heat dissipation property by including the insulating layer 6 having a specific structure.

(Reactor manufacturing method)
The reactor 1 including the insulating layer 6 having the above-described specific structure, in particular, uses a plurality of insulating materials having different hardness after solidification to form a solidified layer having open pores with a certain insulating material, and then another insulating material. Can be produced by filling the open pores and solidifying. FIG. 2 shows an example in which the insulating material filling the open pores is the sealing resin 100. Reactor 1 can be manufactured by the manufacturing method of the reactor of Embodiment 1 provided with the following preparatory processes, a formation process, a solidification process, and a filling process, for example.

-Preparation process In this process, the assembly 10 containing the coil 2 and the magnetic core 3, the metal member, and the insulating material containing resin are prepared. The combined body 10 of this example includes a coil 2 having winding portions 2a and 2b formed by spirally winding the winding 2w, and a laminate (FIG. 4) in which core pieces 31m and gap materials 31g are alternately stacked. A pair of core pieces 32m and 32m and an intervening member 5 (described later) are prepared, and the respective laminates are arranged in the winding portions 2a and 2b, and both laminates, the core pieces 32m and 32m, and the intervening member are arranged. 5 (see the upper figure of FIG. 4 and FIG. 5). The metal member of this example is a metal case 4 having an inner bottom surface 40 i that is a mounting surface of the combined body 10.

  In this example, one of a hard insulating material and a soft insulating material that form the outer region 60 of the insulating layer 6 and the other insulating material that forms the inclusion region 61 of the insulating layer 6 and the sealing resin 100 are prepared. . In particular, the other insulating material that fills the inclusion region 61 has a sufficiently low viscosity at a predetermined temperature, and preferably can be easily filled into the open pores 6p (FIG. 5) that are small and elongated as described later. When a material having a low viscosity is used, filling workability is excellent. Further, it is preferable that the temperature at which the viscosity becomes low is included in the temperature range of the temperature raising process up to a predetermined solidification temperature, because a heating step for filling as a low viscosity is unnecessary, and the productivity is excellent. Such low viscosity includes, for example, about 10 Pa · s or less.

Forming step In this step, as shown in the upper part of FIG. 5, the prepared metal member is placed on the mounting surface (the inner bottom surface 40 i of the case 4, the upper surface in FIG. 5) by using the prepared insulating material. Layer 610 is formed. For the formation of the unsolidified layer 610, application by brush, roll, nozzle, or the like, screen printing, or the like can be used. Formation of the unsolidified layer 610 includes, for example, a hard insulating material having a thermal conductivity of 2.0 W / m · K or more and a Shore A hardness of 70 to 70, including the above-described resin and hard powder such as a ceramic filler. A soft insulating material of about 80 is used.

Formation thickness _{t 610} of the unsolidified layer 610 may be appropriately selected, tends average thickness _{t 600} of the solidified layer 600 after solidification and too thick is large, the winding part 2a of the coil 2, the 2b and the metal member The facing distance between the mounting surface (the inner bottom surface 40i of the case 4) is increased, and the heat dissipation is reduced. Thus, as the average thickness _{t 600} of the solidified layer 600 after solidification becomes a desired size, adjusting the formation thickness _{t 610} of the unsolidified layer 610. Formation thickness _{t 610} of the unsolidified layer 610 is, for example, 50 [mu] m or more 5mm or less in average, and the degree or less than 3mm further 100 [mu] m.

Solidification step In this step, as shown in the middle of FIG. 5, the winding portions 2a and 2b of the combined body 10 are placed on the unsolidified layer 610 and heated, and the winding portions 2a and 2b are made of metal members. While fixing to a mounting surface (inner bottom 40i of case 4), the solidified layer 600 is formed. In particular, the reactor manufacturing method according to the first embodiment has one of the characteristics in the heating condition, from the region on the mounting surface (inner bottom surface 40i) side in the unsolidified layer 610 toward the region on the winding part 2a, 2b side. The unsolidified layer 610 is heated so as to be sequentially solidified.

  As a heating method from the placement surface side of the metal member to the coil 2 side, for example, as shown in the middle part of FIG. 5, a region near the placement surface in which the unsolidified layer 610 is formed in the metal member is mainly heated. A method is mentioned. Specifically, the assembly of the combined body 10 and the metal member that is at room temperature (for example, about 20 ° C. to 25 ° C.) is inserted into a thermostatic bath (not shown) so as to come into contact with or close to the metal member. A heating source 200 such as a heater is disposed on the metal member to mainly heat the metal member. FIG. 5 shows a state in which the heating source 200 is disposed in contact with the outer bottom surface of the bottom 40 of the case 4. When heated in this state, the metal member (the bottom 40 of the case 4) is quickly heated to the set temperature of the heating source 200. However, the combined body 10 has a larger heat capacity than the metal member (mainly the bottom 40), and takes a long time to be heated to the set temperature. An unsolidified layer 610 sandwiched between two members having such a temperature difference, that is, a high-temperature metal member (bottom 40) and a low-temperature combination 10 has a temperature in a region on the metal member (bottom 40) side. Is higher than the temperature of the region of the coil 2 on the winding portions 2a and 2b side. By actively providing such a temperature difference in the unsolidified layer 610, the unsolidified layer 610 is moved from the region on the placement surface (inner bottom surface 40i of the case 4) to the region on the winding part 2a, 2b side. Can be solidified sequentially.

  As another heating method, for example, a method in which an assembly of a combination 10 and a metal member that is set to room temperature (for example, about 20 ° C. to 25 ° C.) is charged in a heating furnace (not shown) such as an atmospheric furnace and heated. Is mentioned. Even in this method, the metal member is quickly heated to the atmospheric temperature of the heating furnace, but the combination 10 having a large heat capacity takes a long time until the entire assembly 10 is heated to the atmospheric temperature. Therefore, as described above, a temperature difference is provided such that the temperature of the region on the metal member (here, the bottom portion 40 of the case 4) side of the unsolidified layer 610 is higher than the temperature of the region on the winding portions 2a and 2b side of the coil 2. Thus, the unsolidified layer 610 can be sequentially solidified from the region on the placement surface (inner bottom surface 40i of the case 4) side toward the region on the winding portions 2a and 2b side.

  The set temperature and the ambient temperature described above may be appropriately selected according to the insulating material constituting the unsolidified layer 610, particularly the resin.

  As described above, the unsolidified layer 610 is sequentially solidified from the region on the metal member placement surface side, whereby the winding portions 2a and 2b of the coil 2 are placed on the metal member placement surface (the inner bottom surface 40i of the case 4). Can be fixed. In addition, as shown in the lower part of FIG. 5, a solidified layer 600 having at least one open hole 6p can be formed between the winding portions 2a and 2b and the metal member (inner bottom surface 40i). The inner peripheral surface of the solidified layer 600 that forms the open pores 6p forms the inner peripheral surface of the outer region 60 of the insulating layer 6 described above.

  The open hole 6p is typically a T-shaped cross section sandwiched between adjacent turns 2t and 2t constituting the winding portions 2a and 2b of the coil 2 and a mounting surface of the metal member (inner bottom surface 40i of the case 4). It is formed in the shape area Ta. The reason for this is not clear, but when the unsolidified layer 610 is solidified as described above, a part of the insulating material constituting the unsolidified layer 610 penetrates between adjacent turns 2t and 2t by capillary action, and the cross section It is conceivable that atmospheric gas was sucked in because the insulating material near the T-shaped region Ta was exhausted. One reason for supporting this consideration is that when the solidified layer 600 is observed after solidification, a part of the insulating material is filled between adjacent turns 2t and 2t.

  The open pores 6p are typically elongated holes provided along the circumferential direction of the turn 2t of the coil 2 from the side surface of the solidified layer 600. The shape or vertical cross-sectional shape of the opening of the open pore 6p is a circular shape or a curved surface shape close to a circle as shown in the broken line circle of FIG. 2 or the lower stage of FIG. Since the open pores 6p are automatically formed when solidified as described above, it is difficult to control the shape and size thereof with high accuracy, but it is confirmed that the open pores 6p tend to be elongated in a circular cross section. Yes.

  A plurality of open pores 6p are typically formed as shown in the lower part of FIG. Each open hole 6p is typically elongated along the circumferential direction of the turn 2t of the coil 2 as described above, and is disposed between the adjacent turns 2t and 2t, and the plurality of elongated open holes 6 are coiled. The two winding portions 2a and 2b are formed in parallel in the axial direction (see also the inclusion region 61 in FIG. 3).

The size of the open pore 6p will be described. When the diameter of the envelope circle of the opening provided on the side surface of the solidified layer 600 or the diameter of the envelope circle of the vertical cross section of the solidified layer 600 is the inner envelope diameter _D6p , the inner envelope diameter _D6p. For example, 2 mm or less is mentioned. Depending on the insulating material constituting the unsolidified layer 610 and the solidified layer 600, the formation thickness _t610 , solidification conditions, etc., the lower limit of the inner diameter _D6p is 0.1 mm, further 0.3 mm, the upper limit is 1.5 mm, Furthermore, 1 mm is mentioned. The inner diameter D _6p of the open pores 6p of the solidified layer 600 is substantially equal to the inner diameter D (FIG. 2) of the inner area 61 provided in the insulating layer 6 described above.

The length (hereinafter referred to as the hole length) along the turn direction of the turn 2t in the elongated open hole 6p is determined by the insulating material forming the unsolidified layer 610 and the solidified layer 600, the formation thickness _t610 , and the solidification condition. According However, for example, based on the width _{W t} of the windings of the coil 2 described above, one-fifth of the width _{W t} of the winding portion, and further not less than 1/4, 1/3 or more, 1/2 or more The width is equal to or less than the width W _t of the winding portion, and further 4/5 or less. The hole length of the open pores 6p of the solidified layer 600 is substantially equal to the rod length L (FIG. 3) of the rod-shaped inclusion region provided in the insulating layer 6 described above.

Since the unsolidified layer 610 is soft to some extent in the mounting of the union 10 described above, pressing the union 10 from above the unsolidified layer 610 causes some of the winding portions 2a and 2b of the coil 2 to be unsolidified. 610 can be embedded. When solidified in this embedded state, the contact area between the winding portions 2a and 2b and the solidified layer 600 increases, and the solidified layer 600 can firmly fix the winding portions 2a and 2b. Note that the average thickness t ₆₀₀ of the solidified layer ₆₀₀ may become thinner than the formation thickness t ₆₁₀ of the unsolidified layer 610 due to this pressing or the weight of the combined body 10. The average thickness t ₆₀₀ of the solidified layer 600 in consideration of the weight of the combined product 10 so that the desired range to adjust the pressing of the above. Even by this pressing, the insulating material constituting the unsolidified layer 610 may be filled between the adjacent turns 2t and 2t.

Filling step In this step, the open pores 6p of the solidified layer 600 are filled with an insulating material having a hardness after solidification different from that of the insulating material constituting the solidified layer 600 and then solidified, and the winding portion 2a of the coil 2 is solidified. , 2b and the metal member mounting surface (inner bottom surface 40i of the case 4), an insulating layer 6 including a plurality of insulating materials having different hardnesses is formed. In particular, the open pores 6p are small as described above and are often elongated. The insulating material containing the resin is in a low-viscosity state that can be filled in the open pores 6p so that the insulating material containing the prepared resin can be filled without gaps in the open pores 6p.

  For example, the insulating layer 6 having the inclusion region 61 can be formed by filling and solidifying a low-viscosity insulating material for each open pore 6p. This method may be used when the reactor does not include the sealing resin 100. In this case, the solidified layer 600 forms the outer region 60, and the insulating material constituting the outer region 60 and the insulating material constituting the inclusion region 61 have different hardnesses (after solidification).

  Furthermore, when it is set as the reactor provided with the sealing resin 100, after forming the insulating layer 6 as described above, the case 4 is filled with an insulating material containing a resin as a raw material of the sealing resin 100 in the case 4. It is better to solidify later. By using a method of filling an insulating material for each open air hole 6p, the insulating material constituting the outer region 60, the insulating material constituting the inclusion region 61, and the insulating material constituting the sealing resin 100 are used. Can vary in hardness (after solidification). Alternatively, the insulating material of the outer region 60 and the insulating material of the sealing resin 100 have the same hardness as the same insulating material, or the insulating material of the inclusion region 61 and the insulating material of the sealing resin 100 have the same hardness as the same insulating material. It can be done.

  As described above, when the constituent material of the encapsulated region 61 of the insulating layer 6 and the constituent material of the sealing resin 100 are the same as the reactor including the sealing resin 100 as in the reactor 1 of the first embodiment, as described above. The solidified layer 600 having the open pores 6p is formed, and in the filling step, the case 4 is filled with the raw material of the sealing resin 100 and then solidified. At the same time that the case 4 is filled with the raw material of the sealing resin 100, an insulating material containing resin can be filled in the plurality of open pores 6p. By solidifying this insulating material, the insulating layer 6 in which a part of the sealing resin 100 is filled in the open pores 6p can be formed, and the reactor 1 including the sealing resin 100 can be simultaneously formed. As the insulating material including the resin used as the raw material of the sealing resin 100, a material having a low viscosity of, for example, about 10 Pa · s or less by being heated in the temperature range of the temperature rising process up to the solidification temperature as described above is used. Then, even if a plurality of small and elongated open holes 6p are provided, each open hole 6p can be easily filled, which is preferable. It is easy to use the insulating material used as a raw material if the viscosity during the temperature rising process is examined in advance.

(Main effect)
Since the reactor 1 of the first embodiment includes the insulating layer 6 between the winding portions 2a and 2b of the coil 2 and the mounting surface of the metal member (for example, the inner bottom surface 40i of the case 4), the coil 2 and the metal member Increases the insulation between. The insulating layer 6 includes both a hard region (for example, the outer region 60) made of a hard insulating material and a soft region (for example, the inclusion region 61) made of a soft insulating material. The heat dissipation is excellent by (3), and noise can be reduced by the following reasons (4) and (5).
(1) The insulating layer 6 does not need to be thick like the vertically stacked structure laminated in the depth direction of the case, and can be made thinner than the vertically stacked structure. As a result, the facing distance between the winding parts 2a and 2b and the placement surface of the metal member can be shortened.
(2) The winding portions 2 a and 2 b of the coil 2 and the metal member are joined by the insulating layer 6.
(3) A hard insulating material containing a resin and a hard powder such as a ceramic filler and having a high thermal conductivity can be used.
(4) The deformation of the soft region can absorb the vibration of the magnetic core 3 and the vibration from the outside, and the transmission of the vibration of the magnetic core 3 and the vibration from the outside to the metal member can be reduced.
(5) The soft region can relieve stress and reduce the stress applied to the hard region, and the hard region that is highly rigid and difficult to deform can reduce the propagation of impact to the soft region, such as vibration, impact, stress, etc. It is possible to reduce cracking, peeling, deformation, etc. of the insulating layer 6 due to the above.

In particular, in the reactor 1 of this example, the heat dissipation is further improved and the noise can be further reduced for the following reasons (6) to (8).
(6) Since the hard region and the soft region are alternately arranged over the entire axial length of the winding portions 2a and 2b of the coil 2, both regions are provided in a well-balanced manner, and the effect of providing both regions is excellent. can get.
(7) Part of the constituent material of the insulating layer 6 is filled between the adjacent turns 2t and 2t, the contact area between the winding portions 2a and 2b and the insulating layer 6 is large, and both are firmly fixed.
(8) The entire metal case 4 can be used as a heat dissipation path.

  In the reactor manufacturing method of the first embodiment, the open pores 6p can be automatically formed by solidifying an unsolidified layer 610 formed of one of a hard insulating material and a soft insulating material under a specific heating condition. The reactor 1 including the insulating layer 6 having a specific structure can be manufactured by filling the open pores 6p with the other insulating material under a specific viscosity condition. That is, the reactor manufacturing method according to the first embodiment can manufacture the reactor 1 according to the first embodiment, which can achieve both the above-described good heat dissipation and noise reduction. Even if the open pores 6p are small and elongated as described above, they can be easily formed by adjusting the conditions during solidification. Further, by adjusting the filling conditions, it is possible to easily fill the insulating material into the small and long open pores 6p. Therefore, the manufacturing method of the reactor of Embodiment 1 can manufacture the reactor 1 of Embodiment 1 with high productivity.

Furthermore, the manufacturing method of the reactor of Embodiment 1 can manufacture the reactor 1 of Embodiment 1 with sufficient productivity for the following reasons (α) to (γ).
(Α) The number of solidification steps of the solidified layer 600 can be reduced as compared with the case where the reactor having the vertically stacked structure described above is manufactured.
(Β) As a soft insulating material, a material having a relatively low viscosity in an unsolidified state such as a material that does not substantially contain hard powder such as the above-mentioned ceramic filler, or a material that contains a small amount of hard powder can be used. It is easy to form the unsolidified layer 610.
(Γ) When the sealing resin 100 is provided, it is possible to use a material that does not substantially contain the hard powder described above, or a material that contains a small amount of the hard powder, and is easy to fill the case 4.

-Details of main members, modified examples, other constituent members-Coil In this example, a form provided with a pair of winding parts 2a, 2b has been described, but a form provided with only one winding part can be adopted. . In this case, the magnetic core 3 may have a known shape called an EE core, an EI core, an ER core, or the like. As the winding 2w, a covered round wire including a round wire conductor and an insulating coating can be used. The winding part can be cylindrical.

..Magnetic Core The core piece 31m in this example has a rectangular parallelepiped shape with rounded corners as shown in FIG. 4, and the gap material 31g is a rectangular flat plate with rounded corners. The core piece 32m of this example has a rectangular parallelepiped block with rounded corners and a pair of protruding portions protruding from the block. The protruding portion protrudes toward the coil 2 side from the inner end surface 32e facing the end surfaces of the winding portions 2a and 2b of the coil 2 in the block. Each protruding portion has a rectangular parallelepiped shape with rounded corners, like the core piece 31m. The outer surface facing the inner end surface 32e in the block is a flat surface, but may be a curved surface or the like.

  Further, in the U-shaped core piece 32m, as shown in FIG. 2, the opposing surface (lower surface) of the case 4 to the inner bottom surface 40i is the opposing surface to the inner bottom surface 40i of the laminate including the core piece 31m. It protrudes from the (lower surface). In this example, when the coil 2 and the magnetic core 3 are assembled, the opposing surface (lower surface) of the block protrudes more than the opposing surface (lower surface) of the winding portions 2a and 2b of the coil 2 with the inner bottom surface 40i. As described above, the block is formed. As a result, a slight gap is provided between the facing surface (lower surface) and the inner bottom surface 40i of the winding portions 2a and 2b as described above, and a part of the sealing resin 100 is filled in the gap. it can. Moreover, the accommodation state in the case 4 is stabilized in the assembly 10 because the said opposing surface (lower surface) in the said block is supported by the inner bottom face 40i. Further, the magnetic core 3 can transfer heat from the block to the inner bottom surface 40i.

  The number, shape, size, composition, and the like of the core pieces 31m, 32m and the gap material 31g can be appropriately changed. For example, the core piece 32m can have a rectangular parallelepiped shape, and the above-described protruding portion can be the core piece 31m. An air gap may be used instead of the gap material 31g, or the gap material 31g may be omitted. When the core piece and the gap material are fixed with an adhesive or the like, it is easy to assemble.

..Metal member When the metal member is the case 4, the case 4 has a form in which the bottom portion 40 and the side wall portion 41 are separate from each other, and are integrally formed in addition to the integrally formed product made of the above-described uniform constituent material. It can be.

  Alternatively, as described in Patent Document 1, the bottom 40 on which the combined body 10 is placed is formed of a metal plate (bottom plate), and the side wall 41 surrounding the combined body 10 is formed of an insulating material such as a resin. It is comprised from goods (wall frame part), and can be set as the form which combined these. The case of this combination is an independent member in which the bottom plate portion and the wall frame portion are detachable. Therefore, in the manufacturing process, the wall frame portion is removed so that only the bottom plate portion is formed, and the assembly 10 is placed and the unsolidified layer 610 is formed with one surface (mounting surface) of the bottom plate portion serving as the inner bottom surface 40i exposed. Can be performed and is excellent in workability. As a result, the productivity of the reactor 1 is excellent. Further, when the wall frame portion is a resin molded product, the insulation between the coil 2 and the side wall portion 41 is excellent, and a lightweight reactor can be obtained. On the other hand, since the bottom plate portion is made of metal and has excellent thermal conductivity, the heat of the winding portions 2a and 2b of the coil 2 can be transmitted to the installation object outside the case 4 through the bottom plate portion.

  As the constituent material of the bottom plate portion, the above-described metal described in the section of the metal case can be used. Examples of the constituent material of the wall frame include insulating materials such as polybutylene terephthalate (PBT) resin, urethane resin, polyphenylene sulfide (PPS) resin, and acrylonitrile-butadiene-styrene (ABS) resin. . The wall frame part can be easily manufactured by a known molding method such as injection molding of the above resin.

  Or the said baseplate part can be used as the composite member by which only the mounting area | region of the assembly 10 was comprised with the metal, and the other area | region was comprised with the nonmetal. As the constituent material of the metal portion, the above-described metal described in the section of the metal case can be used. Examples of the constituent material of the non-metallic part include a non-metallic inorganic material such as a resin material or ceramics constituting the wall frame part.

  As another metal member, the form which is a metal plate attached to an installation object in the state which mounted the assembly 10 is mentioned, for example. This metal plate is used, for example, as a heat radiating member or a fixing member to an installation target. In this embodiment, the periphery of the combined body 10 is not covered with the side wall 41 or the sealing resin 100 of the case 4 described above, and is attached to the installation target in an exposed state. For example, the metal plate is attached to a location where the combination 10 is directly exposed to the liquid refrigerant.

  As the constituent material of the metal plate, the above-described metal described in the section of the metal case can be used. Since the front and back surfaces of the metal plate are usually flat, the metal plate is excellent in the workability of forming the insulating layer 6 and the workability of placing the assembly 10. Since this form does not have a side wall part compared with the form provided with the above-mentioned case, further weight reduction can be achieved.

  Instead of the metal plate, a member on which the combination 10 of the reactor 1 is placed is, for example, a composite member in which only the placement region of the combination 10 is made of metal and the other regions are made of nonmetal. The metal portion of the composite member can be a metal member. As the constituent material of the metal portion, the above-described metal described in the section of the metal case can be used. If the non-metallic portion is made of a non-metallic inorganic material such as ceramics, high heat dissipation and insulation can be expected, and if it is made of resin, the composite member can be easily manufactured by insert molding or the like.

..Encapsulating resin When the sealing resin 100 is provided, in addition to the form in which the constituent material of the sealing resin 100 and a part of the constituent material of the insulating layer 6 are common as described above, the two are completely different forms. Can do. In this case, the degree of freedom in selecting the sealing resin 100 can be increased. For example, the constituent material of the sealing resin 100 may be a material having a higher thermal conductivity than a hard insulating material or a soft insulating material having a high thermal conductivity. For specific resins and additives (such as the above-mentioned ceramic filler) for increasing thermal conductivity, refer to the above-mentioned section of the constituent material of the insulating layer 6.

.. Interposition member The reactor 1 (combination body 10) of this example is provided with the interposition member 5 interposed between the coil 2 and the magnetic core 3, as shown in FIG. The interposition member 5 has a function of improving electrical insulation between the coil 2 and the magnetic core 3 and is made of an insulating material for this function.

  The interposition member 5 in this example is formed by combining a pair of divided members 50a and 50b divided in the axial direction of the winding portions 2a and 2b of the coil 2. Each of the divided members 50a and 50b includes an inner interposed portion 51 interposed between the magnetic core 3 and a portion housed in the winding portions 2a and 2b, and end surfaces of the winding portions 2a and 2b and core pieces. And an end surface interposed portion 52 interposed between the inner end surface 32e of 32 m. The inner interposition part 51 is comprised from the some curved board piece arrange | positioned along the rounded corner | angular part in winding part 2a, 2b. The end portions of the inner interposed portions 51, 51 of the divided members 50a, 50b are formed so as to engage with each other. By making the inner interposition part 51 into a plate piece or the like, it is expected that the raw material (unsolidified insulating material) of the sealing resin 100 is easily filled during manufacture, and that the adjacent turns 2t and 2t can be easily degassed. it can. The end surface interposition part 52 is a frame-shaped flat plate part having two through holes 52h and 52h through which a pair of projecting parts provided in the core piece 32m are inserted. The shape of the interposition member 5 is an example, and can be changed as appropriate. For example, a form in which the lengths of the inner intervening portions 51 in the divided members 50a and 50b are different (substantially equal in this example), an embodiment in which no end of the inner intervening portion 51 is engaged, and an inner interposition The part 51 and the end surface interposition part 52 are not integrated, and each of them can be an independent member.

  Examples of the constituent material of the interposition member 5 include resins such as PPS resin, PTFE resin, LCP, PA resin, and thermoplastic resin such as PBT resin. The interposition member 5 can be easily produced by a known molding method such as injection molding of the above resin. As the interposition member 5, a member having a known shape and composition (sometimes called a bobbin or an insulator) can be used.

... Core covering material Instead of the interposition member 5 described above, the core pieces 31m and 32m of the magnetic core 3 or a laminate of the core piece 31m and the gap material 31g are covered with an insulating material such as the thermoplastic resin described above. Core coating material can be used. By omitting the interposition member 5, the number of assembled parts of the combined body 10 can be reduced, and the assembly workability is excellent. Moreover, it is easy to handle assembly parts by making a plurality of core pieces and the like as one body, and the productivity of the reactor 1 is excellent. Although the core covering material and the above-described interposition member 5 may be omitted, by providing these, the insulation between the coil 2 and the magnetic core 3 can be enhanced.

... Sensor A sensor (not shown) that measures the physical quantity of the reactor 1 such as a temperature sensor, a current sensor, a voltage sensor, or a magnetic flux sensor can be provided.

... Heat dissipation plate A heat dissipation plate (not shown) can be provided at an arbitrary location on the outer peripheral surfaces of the winding portions 2a and 2b of the coil 2 except the surface fixed to the mounting surface of the metal member. For example, when the case 4 is provided, of the outer peripheral surfaces of the winding portions 2 a and 2 b, an arbitrary portion facing the inner peripheral surface of the side wall portion 41 and a surface disposed on the opening side of the case 4 (FIG. 2). Then, a heat sink can be arranged on the upper surface. As the constituent material of the heat sink, non-metallic inorganic materials such as the above-described metals and the above-described ceramics described in the section of the metal case can be used. For example, the heat radiating plate may be fixed with an adhesive or the like.

[Test example]
After forming an unsolidified layer using an insulating material containing resin on the inner bottom surface of a metal case and placing an assembly including a coil and a magnetic core, what is the insulating material used for the unsolidified layer? An insulating material containing another resin was filled and solidified in the case to produce a reactor in which the coil winding portion and the inner bottom surface of the case were joined by the insulating material containing the resin. Details are as follows.

  The reactor manufactured in this test has the configuration described in the first embodiment, that is, a coil having a pair of winding portions in the shape of a rectangular tube with rounded corners, a magnetic core assembled in an annular shape, and a rectangular box-shaped case. And a sealing resin and an insulating layer having a specific structure. The coil is an edgewise coil, the core piece is a green compact, and the case is made of an aluminum alloy. Here, the thing of the magnitude | size about the reactor generally used for a motor vehicle was produced.

  The insulating layer includes an outer region (hard region) made of a hard insulating material and an inclusion region (soft region) made of a soft insulating material. Table 1 shows the specifications of each insulating material. Each insulating material is a commercial product or a blend of a commercially available resin or filler. The viscosities shown in Table 1 were measured in advance. In this test, both thermal conductivity and hardness were measured by preparing test pieces from each insulating material. The thermal conductivity was measured by a laser flash method. The hardness was measured using a commercially available Shore hardness meter.

  In this test, three reactors were formed in which unsolidified layers having different formation thicknesses were formed. Specifically, using a hard insulating material shown in Table 1, unsolidified layers having a formation thickness of 1 mm, 2 mm, and 3 mm are formed on the inner bottom surface of the bottom portion of the case as shown in Table 1, respectively. In this test, an unsolidified layer was formed so as to correspond to a portion arranged in parallel to the inner bottom surface of the case in the combination including the coil and the magnetic core. Specifically, out of the outer peripheral surface of the winding part of the coil, one of the four planes of the rectangular tube shape with rounded corners and the core piece exposed from the winding part among the core pieces of the magnetic core An unsolidified layer was formed so as to be in contact with one surface.

  A case in which the combination was placed on the unsolidified layer (both at room temperature and about 20 ° C. to 25 ° C.) was placed in a constant temperature bath to solidify the unsolidified layer. The set temperature of the thermostatic bath was 140 ° C. and held for a predetermined time.

  When a vertical cross section of the solidified layer is taken after a lapse of a predetermined time, the solidified layer is formed in the region sandwiched between the coil winding portion and the inner bottom surface of the case, and the adjacent turn and inner bottom surface are taken. It was confirmed that open pores were provided in a T-shaped region sandwiched between the two. The average thickness of the solidified layer was adjusted to satisfy the range shown in Table 1. If the thickness of the solidified layer is adjusted, for example, by interposing a spacer between the assembly and the bottom of the case, or by providing a leg piece on the interposed member, the thickness of the solidified layer is desired. Can be as thick as possible.

  After forming the solidified layer, the case was filled with the soft insulating material shown in Table 1, and then the temperature was raised to the solidifying temperature shown in Table 1, and then the solidifying temperature was maintained for a predetermined time to solidify the soft insulating material. In this test, at the time of filling, the soft insulating material was kept at a temperature selected from the range of 50 ° C. to 100 ° C. and filled with a sufficiently low viscosity. By this step, a reactor including a case and a sealing resin was obtained.

Each of the obtained reactors of the three samples was cut along a plane parallel to the axial direction of the coil winding portion, and the longitudinal section was observed. As a result, in each sample reactor, an insulating layer made of an insulating material is interposed between the coil winding portion and the inner bottom surface of the case, and the winding portion and the inner bottom surface are joined by this insulating layer. It was confirmed that In addition, the following was confirmed.
The insulating layer of any sample includes a hard region made of a hard insulating material and a soft region made of an insulating material softer than the hard insulating material.
-As for the insulating layer of any sample, when the longitudinal cross section is seen in the axial direction of the said winding part, a hard area | region and a soft area | region exist alternately.
In any sample insulating layer, the soft region is constituted by a part of the sealing resin.
In each sample insulating layer, the soft region is an inner region surrounded by a hard insulating material, and the hard region forms an outer region.
In any sample insulating layer, the inclusion region is provided in a T-shaped region sandwiched between the adjacent turn and the inner bottom surface of the case.
In any sample insulating layer, the inner diameter D of the inner region is 0.1 mm or more and 2 mm or less.

  Each of the three sample reactors was cut in a plane that was cut by a plane perpendicular to the thickness direction of the insulating layer, and the cross section was observed. As a result, the insulating layer of each sample had a plurality of inclusion regions. The general inclusion area was formed in a bar shape that was formed along the turn direction of the turn and was arranged between adjacent turns.

  As described above, as a reactor in which the coil winding part and the mounting surface of the metal member are joined by an insulating layer, the insulating layer is composed of a plurality of insulating materials having different hardness after solidification, and a hard region and a soft region As described above, it is expected that both good heat dissipation and noise reduction can be achieved by providing the insulating layers having a specific structure such that and are alternately arranged when viewed in the axial direction of the winding portion. This is because the effect of providing a hard region (reduction of impact due to improvement in rigidity, etc.) and the effect of providing a soft region (vibration absorption, stress relaxation, etc.) can be provided in a well-balanced manner.

  In addition, it replaced with charging to a 140 degreeC thermostat, and utilized the hotplate which set temperature as 140 degreeC. Specifically, it has been confirmed that a similar reactor can be produced even when a case including a combined body and an unsolidified layer is placed on a hot plate and placed in a thermostatic bath.

  The present invention is not limited to these exemplifications, but is defined by the scope of claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

  The reactor of the present invention includes various converters such as an in-vehicle converter (typically a DC-DC converter) and an air conditioner converter mounted on a vehicle such as a hybrid vehicle, a plug-in hybrid vehicle, an electric vehicle, and a fuel cell vehicle. It can be used as a component of a power conversion device. The manufacturing method of the reactor of this invention can be utilized for manufacture of the above-mentioned reactor.

DESCRIPTION OF SYMBOLS 1 Reactor 10 Combination 100 Sealing resin 2 Coil 2a, 2b Winding part 2r Connection part 2t Turn 2w Winding 3 Magnetic core 31m, 32m Core piece 31g Gap material 32e Inner end face 4 Case 40 Bottom part 40i Inner bottom face 41 Side wall part 5 Intervening members 50a, 50b Dividing material 51 Inner interposition part 52 End face interposition part 52h Through hole 6 Insulating layer 60 Outer region 61 Inclusion region 600 Solidified layer 6p Open pore 610 Unsolidified layer Ta Cross section T-shaped region 200 Heating source

Claims (11)

A coil having a winding portion formed by spirally winding a winding;
A magnetic core having a portion disposed in the winding portion;
A metal member having a mounting surface of a combination including the coil and the magnetic core;
An insulating layer provided on the mounting surface of the metal member and joining the winding part and the metal member;
The insulating layer includes a resin and is composed of a plurality of insulating materials having different hardnesses, and includes a hard region composed of a hard insulating material and a soft region composed of an insulating material softer than the hard insulating material. Reactors in which regions exist alternately when viewed in the axial direction of the winding portion.   The reactor according to claim 1, wherein the insulating layer includes one of the hard insulating material and the soft insulating material, and includes an inclusion region surrounded by the other insulating material.   The reactor according to claim 2, wherein the inclusion region includes a rod-like body that is formed along a turn direction of the turns constituting the winding portion and is disposed between adjacent turns.   The reactor according to claim 2 or 3, wherein an inner diameter of the inner region in a longitudinal section obtained by cutting the insulating layer along a plane parallel to the axial direction of the winding portion is 0.1 mm or more and 2 mm or less.   The said inclusion | inner_cover area | region is equipped with the cross-section T-shaped area | region pinched | interposed by the adjacent turn which comprises the said winding part, and the mounting surface of the said metal member, The any one of Claims 2-4 Reactor. The metal member is a case for storing the combination.
The reactor according to any one of claims 2 to 5, wherein the insulating material constituting the encapsulating region is a sealing resin that fills the case and embeds at least a part of the combination. The hard insulating material has a Shore D hardness of 50 or more,
The reactor according to any one of claims 1 to 6, wherein the soft insulating material has a Shore A hardness of 80 or less.   The hard insulating material has a thermal conductivity of 2.0 W / m · K or higher and the soft insulating material has a thermal conductivity of 0.1 W / m · K or higher and 5.0 W / m · K or lower. The reactor of any one of Claims 1-7.   The reactor according to any one of claims 1 to 8, wherein the withstand voltage of the insulating layer is 1 kV / mm or more. A combination including a coil having a winding portion formed by winding a winding in a spiral shape and a magnetic core disposed at least partially in the winding portion; and a metal member having a mounting surface of the combination. A preparatory step of preparing an insulating material including a resin;
A forming step of forming an unsolidified layer on the mounting surface using the insulating material,
The wound part of the assembly is placed on the unsolidified layer, and heated so that the unsolidified layer is sequentially solidified from the area on the mounting surface side to the area on the wound part side. A solidification step of fixing the winding portion to the mounting surface and forming a solidified layer having open pores;
The hardness after solidification is different from that of the insulating material, and after filling the insulating material containing resin in a low-viscosity state that can be filled in the open pores, the solidified, and between the winding part and the mounting surface And a filling step of forming an insulating layer including a plurality of insulating materials having different hardnesses.   The said solidification process WHEREIN: The said solidified layer is formed by providing a temperature difference so that the temperature of the area | region by the side of the said metal member in the said non-solidified layer may become higher than the temperature of the area | region by the side of the said winding part. Manufacturing method for the reactor.

Images