JP2015050354A - Method of manufacturing reactor, reactor, converter, and power converter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a reactor in which the resin covering a coil and a magnetic core can be cured uniformly, and to provide a reactor, a converter, and a power converter.SOLUTION: A method of manufacturing a reactor includes a preparation step of preparing a combination where a combination body including a coil and a magnetic core, and a part of accessory members are encased, a filling step of filling the case with uncured resin so that a part of the accessory members are immersed in the resin, and the remaining part of the accessory members is exposed from the resin thus producing a resin filler, and a curing step of curing the uncured resin by blowing hot wind to the resin filler. In the curing step, curing is performed while covering at least the exposure region in the accessory members, exposed from the resin, with a heat transfer cover for relaxing the hot wind.

Description

  The present invention relates to a reactor used for components of a power conversion device such as an in-vehicle DC-DC converter mounted on a vehicle such as a hybrid vehicle, a reactor manufacturing method, a converter including a reactor, and a power conversion device including a converter. About. In particular, the present invention relates to a reactor manufacturing method capable of uniformly curing a resin covering a coil and a magnetic core.

  A reactor is one of the parts of a circuit that performs a voltage step-up operation or a voltage step-down operation. Patent Document 1 discloses a coil formed by winding a winding in a spiral shape as a reactor used in a converter mounted on a vehicle such as a hybrid vehicle, an annular magnetic core on which the coil is disposed, and a coil. A case is disclosed that includes a case that houses a combination with a magnetic core, and a sealing resin that fills the case and covers the combination. A terminal member (terminal fitting) is connected to the end of the winding. An external device such as a power source and the coil are connected via the terminal fitting, and power is supplied to the coil.

  In Patent Document 1, the region from the connection end of the terminal fitting to the winding to the middle portion of the connection end with the external device is housed in a case and embedded in the sealing resin, and the terminal fitting is made of the sealing resin. The structure fixed to a case is disclosed.

JP 2012-209341 A

  For a reactor including a resin that covers a combined body of a coil and a magnetic core and functions as a sealing material, it is desired that the resin does not crack.

  For example, as described in Patent Document 1, the reactor including the resin can be manufactured by storing the combination in a case, filling the case with uncured resin, and curing the resin. . For curing the resin, for example, a hot-air type curing tank including a heat source and a fan can be used. This curing tank can maintain a constant temperature by spreading hot air and warm air uniformly in the tank by a fan. However, when a hot-air type curing tank is used, a region where the temperature is locally high may occur in the uncured resin after the object is stored in the curing tank and before reaching a predetermined curing temperature. . And the area | region where this temperature is high reaches | attains hardening temperature or the temperature of the vicinity before other area | regions, and can harden | cure first. As a result, the entire resin may not be uniformly cured / shrinked. Also, when subjected to thermal shock after curing, cracks tend to occur starting from the previously cured portion (considered). That is, it can be said that the above-mentioned hardened portion (considered) can be a portion that determines the life of the resin. Therefore, especially when the resin is cured using hot air, the development of a method capable of uniformly curing the entire resin by suppressing the uneven temperature of the target and raising the temperature of the uncured resin uniformly. desired.

  Then, one of the objectives of this invention is providing the manufacturing method of the reactor which can harden | cure resin which covers the assembly provided with a coil and a magnetic core uniformly.

  Another object of the present invention is to provide a reactor in which cracking or the like hardly occurs in a resin covering an assembly including a coil and a magnetic core.

  The other object of this invention is to provide a converter provided with the said reactor, and a power converter device provided with this converter.

The manufacturing method of the reactor of this invention is equipped with the following preparatory processes, a filling process, and a hardening process.
Preparation process The process which prepares the assembly by which the assembly provided with a coil and a magnetic core, and a part of attachment member were accommodated in the case.
Filling step Filling the case with uncured resin, a part of the attachment member is immersed in the resin, and the remaining portion of the attachment member is a resin filling exposed from the resin.
Curing step A step of blowing the hot air to the resin filling to cure the uncured resin.
In the curing step, curing is performed in a state in which at least an exposed region of the attachment member exposed from the resin is covered with a heat transfer cover that relaxes the hot air.

  The method for manufacturing a reactor of the present invention can uniformly cure a resin that covers an assembly including a coil and a magnetic core.

It is a schematic perspective view which shows the reactor of Embodiment 1. FIG. It is a top view which shows the outline of the reactor of Embodiment 1. FIG. It is a disassembled perspective view which shows the outline of the reactor of Embodiment 1. FIG. It is a disassembled perspective view which shows the outline of the assembly provided with the coil and magnetic core with which the reactor of Embodiment 1 is equipped. It is explanatory drawing explaining the hardening process of the manufacturing method of the reactor of Embodiment 1. FIG. Sample No. using a heat transfer cover in the curing process. 1 is a graph showing a temperature change of a resin over time. Sample No. which does not use a heat transfer cover in the curing process. It is a graph which shows the time-dependent temperature change of resin about 100. FIG. It is a schematic perspective view which shows the reactor of Embodiment 2. 1 is a schematic configuration diagram schematically showing a power supply system of a hybrid vehicle. It is a schematic circuit diagram which shows an example of the power converter device of Embodiment 4 provided with the converter of Embodiment 4.

[Description of Embodiment of the Present Invention]
The present inventor examined various conditions in curing an uncured resin covering a combined body including a coil and a magnetic core with hot air. As a result, the reactor has an accessory member (for example, a terminal fitting) that is susceptible to hot air, and a part of the accessory member is contacted or immersed in the uncured resin, and the remaining part is exposed from the resin to generate hot air. In the case of direct contact or strong contact, it was found that the contact region of the resin with the accessory member and the region in the vicinity thereof are likely to be locally hot. In addition, when a low temperature test or a heat cycle test is performed after curing, the knowledge that cracks are likely to occur starting from a region that tends to be high temperature in the above resin, or surface defects such as heat sinks are likely to occur in this region. Got. The reason is considered as follows.

  In the above-described resin, the region where the temperature tends to be high can be cured by increasing the rate of temperature rise compared to other regions, reaching the curing temperature or a temperature close thereto, and starting the curing earlier. The portion that has been hardened first receives stress due to thermal shrinkage when the uncured portion is hardened later, and the internal stress tends to increase. Therefore, the internal stress of the cured resin tends to be non-uniform. The cured resin has a variation in internal stress, and there are parts where the internal stress is locally high. It is thought that etc. occur.

  Therefore, when the exposed area of the attachment member is covered with a heat transfer cover that does not directly hit the exposed area from the resin in the attachment member and can transfer heat necessary for curing the resin well, The knowledge that the temperature rising state up to the curing temperature can be made uniform was obtained. Further, as a result, it was found that the start of curing can be made almost the same over the entire resin, and curing can be performed uniformly. The present invention is based on the above findings.

  First, the contents of the embodiment of the present invention will be listed and described.

(1) The manufacturing method of the reactor which concerns on embodiment is provided with the following preparatory processes, a filling process, and a hardening process.
Preparation process The process which prepares the assembly by which the assembly provided with a coil and a magnetic core, and a part of attachment member were accommodated in the case.
Filling step Filling the case with uncured resin, a part of the attachment member is immersed in the resin, and the remaining portion of the attachment member is a resin filling exposed from the resin.
Curing step A step of blowing the hot air to the resin filling to cure the uncured resin. In this step, curing is performed in a state where at least an exposed area of the attachment member exposed from the resin is covered with a heat transfer cover that relaxes the hot air.

  A part of the accessory member is housed in a case together with a combined body including a coil and a magnetic core and embedded in a resin, and the remaining part is exposed from the resin. The reactor part is integrated with the case and used. In particular, the constituent material of the attachment member includes a material having a higher thermal conductivity than that of the resin. Specific attachment members include terminal fittings, heat dissipation members, bus bars (a connecting member described later, FIG. 8), and the like.

  The manufacturing method of the reactor of embodiment can prevent that a hot air hits the said exposure area | region directly by covering at least the exposure area | region of an attachment member with a heat-transfer cover. Therefore, in the process until reaching a predetermined curing temperature (the initial stage of the curing process), it is possible to suppress the contact area of the uncured resin with the attachment member and the area in the vicinity thereof from becoming higher than other areas. In addition, since the heat transfer cover allows heat to be transferred into the heat transfer cover, the temperature inside the heat transfer cover and the part outside the heat transfer cover can be raised in an uncured resin in the same manner. Can be cured simultaneously. Therefore, the method for manufacturing a reactor according to the embodiment can uniformly cure the resin covering the combined body including the coil and the magnetic core. Moreover, since the manufacturing method of the reactor of embodiment can suppress the dispersion | variation in the temperature of the resin in a hardening process, it is hard to produce the part hardened | cured previously in uncured resin. Therefore, the reactor manufacturing method according to the embodiment can manufacture a reactor in which internal stress is uniformly present and cracks are not easily generated.

  (2) As an example of the manufacturing method of the reactor which concerns on embodiment, the form with which the said heat-transfer cover was comprised with the cloth is mentioned.

  The said form can fully relieve a hot air with the softness | flexibility of cloth itself. In addition, the cloth has sufficient pores, and heat can be sufficiently transferred into the cover using the pores. Therefore, the above-mentioned form is a practical time without excessively increasing the curing time of the resin as compared with the case of using a cover made of a material having substantially no pores such as a metal foil or a resin sheet. Suitable for industrial mass production of reactors.

  (3) As an example of the manufacturing method of the reactor which concerns on embodiment, the form by which the side wall part of the said case was comprised with resin is mentioned.

  In the above form, since the side wall of the case that is susceptible to hot air is formed of a resin that is generally inferior in thermal conductivity because it has a relatively large area in the reactor, the attachment member has a relatively high thermal conductivity. Can be a thing. By covering the exposed area of such an attached member with a heat transfer cover, the above-mentioned form prevents the contact area with the attached member in uncured resin and the area in the vicinity thereof from becoming high temperature, and the entire resin The temperature can be increased uniformly and cured uniformly.

  (4) As an example of the manufacturing method of the reactor which concerns on embodiment, the form which is a terminal metal fitting with which the said attachment member is connected to the edge part of the coil | winding which forms the said coil is mentioned.

  The terminal fitting is typically made of a material having excellent conductivity such as copper or a copper alloy. Since copper and copper alloys have high thermal conductivity, it can be said that when such a terminal fitting is provided, the contact area of the uncured resin with the terminal fitting and the area in the vicinity thereof are likely to become high temperature. By covering the exposed area of the terminal fitting with a heat transfer cover, the contact area of the uncured resin with the terminal fitting and the area in the vicinity thereof are prevented from becoming high temperature, and the entire resin is uniformly formed. The temperature can be raised and cured uniformly.

  (5) As an example of the manufacturing method of the reactor according to the embodiment, there is a form in which the exposed region of the attachment member has a portion wider than the width of the winding forming the coil (hereinafter referred to as a wide portion). .

  In the above-described embodiment, since the attached member has a wide portion, the exposed region of the attached member is more susceptible to hot air. By receiving the hot air in the exposed region, the contact region of the uncured resin with the attachment member and the vicinity thereof are likely to become high temperature. In the above embodiment, such an exposed region is covered with a heat transfer cover, so that the contact region of the uncured resin with the attachment member and the region in the vicinity thereof are prevented from becoming high temperature, and the entire resin is uniformly formed. The temperature can be raised and cured uniformly.

  (6) As an example of the method for manufacturing a reactor according to the embodiment, in the curing step, there is a mode in which curing is performed in a state where the entire resin filling is covered with the heat transfer cover.

  Compared with the case where the heat transfer cover is disposed only on a part of the resin filling, the above-described form can easily arrange the heat transfer cover and has excellent workability, and thus contributes to the improvement of the reactor productivity. be able to.

  (7) As an example of the method for manufacturing the reactor according to the embodiment, a form in which the attachment member is made of a material having higher thermal conductivity than that of the constituent material of the case can be cited.

  When an attachment member having a higher thermal conductivity than the case is provided, it can be said that the region in the vicinity of the attachment member in the resin is likely to become high temperature. Although the said form is equipped with such an attachment member, uniform hardening can be performed by utilizing a heat-transfer cover. In this embodiment, the thermal conductivity of the attachment member is higher than the material having the highest thermal conductivity among the main constituent materials of the portion in contact with the resin in the case. Examples of the combination of the attachment member and the constituent material of the case that satisfy this relationship include the following. (Attachment member, case) = (metal, resin), (copper or copper alloy, aluminum or aluminum alloy), (high thermal conductive ceramics, resin), etc.

  (8) The reactor which concerns on embodiment is manufactured by the manufacturing method of the reactor described in any one of the said embodiment (1)-(7).

  The reactor of the embodiment is manufactured by the manufacturing method of the reactor of the embodiment, so that the resin is uniformly cured, the variation of internal stress is small over the entire resin, and the internal stress exists uniformly. . Therefore, the reactor of the embodiment hardly causes cracking in the resin, and preferably does not substantially crack. In particular, the reactor according to the embodiment can reduce the occurrence of cracks due to the contact region of the resin with the attachment member and the vicinity thereof as the starting point of the crack. Therefore, it is expected that the reactor according to the embodiment is less likely to cause the above-described crack even when subjected to a thermal shock or the like, and can achieve a long life. In addition, the reactor of the embodiment can reduce heat sinks, particularly heat sinks that can occur in the contact region with the above-mentioned accessory member and the vicinity thereof, as the resin is uniformly cured, and is excellent in surface properties and appearance.

  (9) The converter which concerns on embodiment is provided with the reactor which concerns on the said embodiment.

  The converter of the embodiment can suppress shortening of life due to the cracking of the resin by including the reactor of the embodiment in which the resin is hardly cracked.

  (10) The power converter device which concerns on embodiment is provided with the converter which concerns on the said embodiment.

  The power converter device of embodiment can suppress the shortening of life resulting from the crack of resin by providing the reactor of embodiment which is hard to produce a crack in resin.

[Details of the embodiment of the present invention]
Hereinafter, the reactor according to the embodiment of the present invention and the manufacturing method thereof will be described more specifically. In addition, this invention is not limited to these illustrations, is shown by the claim, and is intended that all the changes within the meaning and range equivalent to the claim are included.

[Embodiment 1]
With reference to FIGS. 1-5, the reactor 1A of Embodiment 1 is demonstrated. In the drawings, the same reference numerals denote the same names.

(Reactor overall configuration)
As shown in FIG. 1, the reactor 1 </ b> A includes a coil 2 </ b> A formed by spirally winding a winding 2 w, a magnetic core 3 that is disposed inside and outside the coil 2 </ b> A to form a closed magnetic path, and a coil 2 </ b> A and a magnetic core 3 The case 4A is stored, and the resin 100 that is filled in the case 4A and seals the combination 10 is provided. The reactor 1A shown in this example further includes terminal fittings 8 and 8 connected to the respective ends of the winding 2w. Part of the terminal fittings 8 and 8 (the connecting portion 812 (FIGS. 2 and 3) connected to the joint 81 with the winding 2w) is embedded in the resin 100 and the remaining portion (mainly fixed to the case 4A). The region and the region on the connection side with an external device (not shown) are exposed from the resin 100. Reactor 1A is a form provided with the attachment member (here terminal fitting 8) integrated in assembly 10 through resin 100 in this way. Such a reactor 1A is typically used by being attached to an installation target such as a cooling base (not shown). In FIG. 2, the resin 100 is omitted.

  And reactor 1A can be manufactured with the following specific manufacturing methods, for example. Hereinafter, an outline of a basic configuration of the reactor 1A, a manufacturing method, and main effects based on the manufacturing method will be described first.

As shown in FIGS. 1 to 4, the combined coil 2 </ b> A includes a pair of coil elements 2 a and 2 b formed by one continuous winding 2 w having no connection portion, and both coil elements 2 a and 2 a. 2b for connecting 2b. The winding 2w is a covered wire having a rectangular wire as a conductor. Each coil element 2a, 2b is a rectangular cylindrical edgewise coil with rounded corners, and is arranged in parallel (side by side) so that the respective axial directions are parallel. The coil elements 2a and 2b have the same number of turns, and the coil elements 2a and 2b are electrically connected in series. The connecting portion 2r is formed by bending a part of the winding 2w forming the coil elements 2a and 2b into a U shape. Here, the connecting portion 2r is provided so that a part of the turn forming surfaces of the coil elements 2a and 2b (upper surface in FIGS. 3 and 4) and the connecting portion 2r are substantially flush with each other. On the other hand, both end portions of the winding 2w to which the terminal fitting 8 is connected project in a direction orthogonal to the axial direction from a part of the turn forming surface of the coil elements 2a and 2b (upper surface in FIGS. 3 and 4). It is provided as follows.

  Here, as shown in FIG. 4, the magnetic core 3 includes a pair of columnar inner core portions 31 and 31 and a pair of columnar outer core portions 32 and 32. Each inner core part 31 and 31 is inserted and arranged in the coil elements 2a and 2b arranged side by side, and is used as an arrangement part of the coil 2A. The outer core portions 32 and 32 are portions exposed from the coil 2 </ b> A without the coil 2 </ b> A being substantially disposed. Outer core parts 32 and 32 are arranged so as to connect both inner core parts 31 and 31 arranged side by side to form an annular magnetic core 3. It is easy to maintain an annularly assembled state by appropriately joining the inner core portion 31 and the outer core portion 32 with an adhesive or an adhesive tape.

  Here, each inner core portion 31 includes a plurality of core pieces 31m made of a soft magnetic material molded body (in this example, a compacted body), and a plurality of materials made of a material having a lower relative permeability than the core piece 31m. The gap material 31g is alternately laminated (within the one-dot chain line circle in FIG. 4). Further, here, the core parts 5A and 5B in which the outer peripheral surface of the laminate is covered with an insulating resin are used. The core parts 5A and 5B are identical in shape when they are rotated 180 ° in the horizontal direction in the state shown in FIG. Each of the core parts 5A and 5B is integrally formed with a laminate (inner core portion 31) of the core piece 31m and the gap material 31g, a peripheral surface covering portion 51o covering the outer periphery of the laminate, and the peripheral surface covering portion 51o. And a frame plate portion 52 interposed between the end surfaces of the coil elements 2a and 2b and the inner end surface 32e of the outer core portion 32 (details will be described later). By using the core parts 5A and 5B as the constituent elements, the insulation between the coil 2A and the magnetic core 3 can be enhanced by the peripheral surface covering portion 51o and the frame plate portion 52, or the certainty of positioning of both can be enhanced. can do. Each of the outer core portions 32 is a soft magnetic material molded body (in this example, a compacted body).

Case The case 4A includes a bottom plate portion 40 on which the combined body 10 of the coil 2A and the magnetic core 3 is placed, and a side wall portion 41 erected from the bottom plate portion 40, and faces the bottom plate portion 40 (see FIG. 1 is an open box. As shown in FIG. 3, the case 4 </ b> A shown in this example is a flat bottom plate portion 40 that constitutes the bottom portion of the case 4 </ b> A and a frame-like side wall portion that constitutes the wall portion of the case 4 </ b> A in the manufacturing process of the reactor 1 </ b> A. 41 is an independent member. In the completed state of the reactor 1A, as shown in FIG. 1, the bottom plate portion 40 and the side wall portion 41 are integrally fixed by a fixing member (described later) to be formed in a box shape.

  Here, the bottom plate part 40 and the side wall part 41 are made of different materials. Specifically, the bottom plate portion 40 is made of a metal such as an aluminum alloy, and functions as a heat radiating member (heat radiating path) that transfers the heat of the coil 2A to the outside. In particular, in the reactor 1A, the combined body 10 of the coil 2A and the magnetic core 3 and the bottom plate portion 40 are joined by the joining layer 42, so that the heat of the coil 2A can be transmitted to the bottom plate portion 40, and the heat dissipation is excellent. . Further, by making at least a part of the constituent material of the case 4A a light metal such as aluminum or an alloy thereof, it is possible to contribute to the weight reduction of the reactor 1A. Here, the bottom plate portion 40 has a rectangular plate shape, and projecting pieces projecting outward are integrally formed at the four corners of the rectangular plate, and each projecting piece is attached to the side wall portion 41 ( Here, a connecting hole 40h to which the connecting bolt 4b (FIG. 2) is attached, and an attachment portion 400 that is an attachment location to the installation target are configured.

  The side wall 41 is made of a resin such as polyphenylene sulfide (PPS) resin and is relatively hard, so that the rigidity of the case 4A can be increased. Since such a hard side wall 41 and the resin 100 are present in an annular shape so as to surround the periphery of the combined body 10 of the coil 2A and the magnetic core 3, the reactor 1A can generate vibration and noise caused by the vibration. Can be suppressed. Moreover, the electrical insulation between coil 2A and case 4A can be improved because the side wall part 41 is resin. Therefore, by arranging the coil 2A and the side wall portion 41 close to each other (for example, the distance between the coil 2A and the inner surface of the side wall portion 41 is about 0 mm to 1.0 mm), the reactor 1A can be downsized. . Furthermore, when the side wall part 41 is resin, it can contribute to the weight reduction of the reactor 1A. In addition, the side wall portion 41 shown in this example has a rectangular frame shape and a pair of flange portions 410 and 410 so as to cover the upper end surfaces of the outer core portions 32 and 32 of the combined body 10 housed in the case 4A. Is provided. One brim part 410 includes a fastening base part 415 to which the terminal fitting 8 is fixed, and is used for the terminal base. In addition, projecting pieces projecting outward are integrally formed on the four corners of the rectangular frame, and each projecting piece is attached to a bottom plate portion 40 (here, a connecting bolt 4b (FIG. 2) is attached). 41h) to be installed, and an attachment portion 411 to be an attachment location to the installation object. Even if the side wall 41 has such a complicated three-dimensional shape, it can be easily molded by injection molding or the like by using resin as a constituent material, and is excellent in manufacturability. However, since the side wall 41 is made of resin, it has lower thermal conductivity than the metal bottom plate 40 (thermal conductivity of the side wall 41: 0.2 W / m · K or more and 0.8 W / m · K or less).

・ Resin (encapsulant)
The resin 100 is filled in the case 4A and has a function of integrally fixing the combined body 10 of the coil 2A and the magnetic core 3, a function of absorbing vibration and suppressing noise, and a covering portion (an embedded portion) in the combined body 10 ) Mechanical protection and protection from the environment, a function as a heat dissipation path, and a function of separating the assembly 10 and its surrounding parts to enhance insulation, and so on.

  Specific examples of the resin 100 include an epoxy resin, a urethane resin, and a silicone resin. Insulating resin is particularly preferable. If the resin 100 is made of an elastic material capable of absorbing vibrations caused by magnetostriction or has a thickness capable of absorbing vibrations caused by magnetostriction, vibration and noise can be suppressed satisfactorily. A relatively hard resin such as an epoxy resin is preferable because a vibration / noise suppression function can be satisfactorily obtained.

The resin 100 contains a filler made of ceramics such as silicon nitride (Si ₃ N ₄ ), alumina (Al ₂ O ₃ ), aluminum nitride (AlN), boron nitride (BN), silicon carbide (SiC), and mullite. be able to. By including a filler made of at least one kind of the above ceramics, the heat dissipation and insulation of the resin 100 can be further enhanced. Depending on the filler material, vibration and noise suppression effects can also be expected.

  The thermal conductivity of the resin 100 is about 1 W / m · K or less. Specifically, it is about 0.1 W / m · K or more and about 0.6 W / m · K or less for epoxy resin or silicone resin, and about 0.6 W / m · K or less for urethane resin, and 0.1 W / m · K for urethane resin. It is about 0.6 W / m · K or less. When a filler is contained, the thermal conductivity changes depending on the material and content of the filler. For example, in the case of an epoxy resin with a filler, it is 0.5 W / m · K or more, further 1 W / m · K or more, particularly 2 W / m · K or more and 20 W / m · K or less. In the case of the silicone resin with filler, it is about 0.7 W / m · K or more and 0.9 W / m · K or less. In the case of a urethane resin with a filler, it is about 0.2 W / m · K or more and 0.7 W / m · K or less.

  The filling area | region of the resin 100 with respect to case 4A can be selected suitably. In this example, as shown in FIG. 1, the entire combination 10 of the coil 2 </ b> A and the magnetic core 3 is substantially embedded except for the end portion to which the terminal fitting 8 is connected in the winding 2 w. By doing so, protection of the combined body 10 from the external environment, improvement of rigidity as an integrated body including the combined body 10, the case 4A, and the resin 100, improvement of heat dissipation when the resin 100 is used as a heat dissipation path, etc. The effect can be expected. By exposing both ends of the winding 2w from the resin 100, regardless of the presence or absence of the resin 100, the connection work between the winding 2w and the terminal fitting 8 (for example, after crimping the U-shaped joint 81, TIG ( Tungsten Inert Gas) welding, crimping, soldering, etc.) can be performed easily and at any time, and the workability is excellent. After joining the end of the winding 2 w and the terminal fitting 8, an uncured resin is filled, and the joining portion can be embedded in the resin 100.

  A part of the coil 2A (for example, the upper surface of the coil elements 2a and 2b in FIG. 1) and a part of the magnetic core 3 (for example, a part of the outer core part 32) may be exposed from the resin 100. . Further, in the form in which the connecting part 2r of the coil 2A is raised and protruded from the upper surfaces of the coil elements 2a and 2b, the connecting part can be exposed from the resin 100. In these forms, it is conceivable that the region exposed from the resin 100 (here, the copper winding 2w or the like) has a higher thermal conductivity than the case 4A (here, the resin side wall 41 in particular). Then, the vicinity of this exposed region in the resin 100 can be said to be a region that is likely to become hot when the resin is cured using hot air, as in the case of an attachment member (terminal fitting 8 here) described later. Therefore, it is considered that a specific manufacturing method described later can be suitably used for manufacturing this form.

-Terminal metal fitting The terminal metal fitting 8 is a electrically-conductive member formed from the strip | belt board material here. Examples of the constituent material of the terminal fitting 8 include conductive materials such as copper (398 W / m · K), copper alloy, aluminum (237 W · m / K), and aluminum alloy. The terminal fitting 8 shown in this example is made of tin-plated copper and can be said to be an accessory member having a higher thermal conductivity than the resin 100. Furthermore, the terminal metal fitting 8 can be said to be an accessory member having a higher thermal conductivity than the constituent material of the case 4A and at least the main constituent material of the side wall 41 (here, PPS resin). Furthermore, it can be said that the terminal fitting 8 shown in this example is an accessory member having a higher thermal conductivity than the entire case 4A including the aluminum alloy constituting the bottom plate portion 40. That is, the terminal fitting 8 shown in this example is a material (here, an aluminum alloy) having the highest thermal conductivity among the main constituent materials of the portion (here, the bottom plate portion 40 and the side wall portion 41) that can contact the resin 100 in the case 4A. It is an attachment member having higher thermal conductivity than that.

  The shape of the terminal fitting 8 can be selected as appropriate. The terminal fitting 8 shown in this example is formed by punching a material plate into a desired shape and bending it into a desired shape. Briefly speaking, the terminal fitting 8 has a U-shaped joining portion 81 to which the end of the winding 2w is joined on one end side in the longitudinal direction of the strip as shown in FIG. A fixing region having a through hole into which a connecting member (typically a bolt) for connecting an external device such as a power source is fitted, and being fixed to the side wall portion 41 (here, the fastening base portion 415) in the middle portion Have The fixing region includes a fixing hole 85 through which a fastening member (here, a bolt 419) is inserted.

  Further, in the terminal fitting 8 shown in this example, the region on the connection side with the external device having the through hole is lower than the joining portion 81 and the fixing region with the winding 2w (the terminal fitting 8 is fixed to the side wall portion 41). In this case, it is formed in a slide shape so as to be a position close to the bottom plate portion 40). The connecting portion 812 that connects the fixed region and the joint portion 81 is also provided at a position lower than both the joint portion 81 and the fixed region. The connecting portion 812 is a portion embedded in the resin 100 in the terminal fitting 8, and the remaining portion of the terminal fitting 8 (joint portion 81, region extending from the fixed region to the connection side region with the external device) is covered with the resin 100. This is an exposed region exposed from the resin 100 (FIG. 1). 3 shows a state in which the terminal fitting 8 outside the one-dot chain line circle (shown on the left side in FIG. 3) is rotated by 180 ° in the horizontal direction. The total number of terminal fittings 8 attached to the end of 2w is two.

  In addition, the terminal fitting 8 has a small or substantially no step between the connection-side region with the winding 2w and the connection-side region with the external device as in Patent Document 1, for example, and the side wall portion 41 in the middle portion. And a region on the connection side with the winding 2 w is embedded in the resin 100. Further, the joint portion 81 can be formed in a flat plate shape instead of a U shape.

  In particular, in the terminal fitting 8 shown in this example, a region extending from the fixed region to the connection side region (the other end side region) with the external device is a rectangular region having a uniform width, and is fixed from the connecting portion 812. It is wider than the width of the strip material that forms the region up to the region. Specifically, the width of the rectangular region is sufficiently wider than the width of the winding 2w (here, the width of the covered rectangular wire), and here is twice or more the width of the covered rectangular wire. That is, the terminal fitting 8 has the above rectangular parallelepiped region as a wide portion wider than the width of the winding 2w. The size (width) of the wide portion can be, for example, 1.5 times or more, more than 2 times, particularly 2.5 times or more the width of the winding.

(Reactor manufacturing method)
Reactor 1A can be manufactured through the following steps (1) to (3), for example. Hereinafter, description will be made with reference to FIGS. 3 and 5 as appropriate.

(1) Preparatory process In this process, the assembly 10 in which the assembly 10 of the coil 2A and the magnetic core 3 and a part of the attached member (here, the terminal fitting 8) is accommodated in the case 4A is prepared.

  Here, the assembled body 10, the bottom plate portion 40 and the side wall portion 41, which are components of the case 4A, and the terminal fitting 8 are prepared. A double-sided adhesive sheet to be the bonding layer 42 is disposed on one surface of the bottom plate portion 40 (a mounting surface (inner surface) on which the combined body 10 is placed), an adhesive is applied, or screen printing is performed. In this example, since the bottom plate portion 40 and the side wall portion 41 are independent as described above, when an adhesive sheet is placed on the bottom plate portion 40 with the side wall portion 41 removed, an adhesive is applied, etc. Excellent workability.

  Here, the terminal fitting 8 is fixed to the side wall 41. Specifically, the fixing regions of the terminal fittings 8 and 8 are respectively arranged on the pair of fastening base portions 415 and 415 that are integrally formed with the side wall portion 41 and project from one flange portion 410. Each fastening base 415 is provided with a pair of positioning protrusions 417 and 417. Each terminal fitting 8 is provided with a positioning hole 87h through which one positioning projection 417 is inserted and a positioning notch 87 which locks the other positioning projection 417. Furthermore, the terminal fitting 8 is provided with a protruding piece-like hooking portion 86, and an insertion hole 416 into which the hooking portion 86 is inserted is provided on the end surface of the wall portion 413 erected so as to be orthogonal to the surface of the flange portion 410. It has been. By inserting the positioning hole 87 h into the positioning protrusions 417 and 417, locking the positioning notch 87, and inserting the latching portion 86 into the insertion hole 416, the terminal fitting 8 is fixed to the side wall 41. Can be easily and accurately arranged at the position (tightening base portion 415). After the terminal fitting 8 is arranged, the bolt 419 is tightened to fix the terminal fitting 8 to the fastening base 415 (side wall 41). At this time, the terminal fitting 8 has a fastening base portion 415 to the extent that it can stand on its own by engaging the positioning protrusions 417 and 417 with the positioning hole 87 h and the positioning notch 87 and engaging the latching portion 86 and the insertion hole 416. Since it is supported by non-rotatable, it is easy to perform the tightening operation. By tightening the bolt 419, the side wall portion 41 including the terminal fitting 8 can be obtained. In addition, what is necessary is just to fix the terminal metal fitting 8 to the side wall part 41 before filling the case 4A with uncured resin 100A (FIG. 5). For example, the terminal fitting 8 may be fixed to the side wall 41 after the case 4A is assembled.

  The combined body 10 is placed on an adhesive sheet or an adhesive coating layer provided on the bottom plate portion 40, and the side wall portion 41 is placed on the bottom plate portion 40 by covering the side wall portion 41 from above the combined body 10. The outer peripheral surface of the combined body 10 is surrounded by the side wall 41. And the connecting bolt 4b (FIG. 2) is fastened to the connecting hole 40h provided in the attaching part 400 of the bottom plate part 40 and the connecting hole 41h provided in the attaching part 411 of the side wall part 41, and the bottom plate part 40 and the side wall part 41 are tightened. And fix.

  Here, the side wall portion 41 can be disposed on the bottom plate portion 40 so that the U-shaped joint portion 81 of the terminal fitting 8 is fitted into the end portion of the winding 2w. That is, the end portion of the winding 2 w and the U-shaped joint portion 81 can be used for positioning the side wall portion 41 with respect to the guide and the bottom plate portion 40. In addition, an inclined piece (induction part) 810 extending from the joint 81 is provided on the insertion side of the winding 2w in the U-shaped joint 81 (FIG. 3). When the side wall 41 is covered from the upper side of the combined body 10, the end of the winding 2w hits the inclined piece 810 and can be easily inserted into the U-shaped portion, and the insertability of the end of the winding 2w is excellent. Further, here, the side wall portion 41 includes a protrusion (not shown) protruding from the bottom surface of the mounting portion 411, and the bottom plate portion 40 includes a hole into which the protrusion is inserted into the mounting portion 400. These protrusions and holes also function as a guide and positioning when the bottom plate portion 40 and the side wall portion 41 are assembled.

  After the connecting bolt 4b is tightened, the temperature is appropriately set according to the material of the adhesive sheet or the adhesive to be cured appropriately to form the joining layer 42, and the assembly 10 and the bottom plate portion 40 are joined by the joining layer 42. Here, the size of the bonding layer 42 is adjusted so that the bottom plate portion 40 and the side wall portion 41 are also bonded by the bonding layer 42. Moreover, since the hardening process of the joining layer 42 and the hardening process of the adhesive agent which joins the baseplate part 40 and the side wall part 41 can be performed simultaneously here, a hardening process can be reduced and it is excellent in manufacturability of the reactor 1A. In this reactor 1A, the joining layer 42 and the above-described connecting bolt 4b are used in combination as a fixing member for the bottom plate portion 40 and the side wall portion 41.

  Through the above-described steps, an assembly 10 in which the combined body 10 of the coil 2A and the magnetic core 3 and a part of the terminal fitting 8 (connecting portion 812) are accommodated in the case 4A is obtained.

(2) Filling Step In this step, as shown in FIG. 5, the case 4A containing the combined body 10 of the coil 2A and the magnetic core 3 is filled with an uncured (liquid) resin 100A to obtain a resin filling 10A. . In particular, a part of the attachment member (here, the connecting portion 812 of the terminal fitting 8) is immersed in the resin 100A, and the remaining portion of the attachment member (here, mainly the joining portion 81 of the terminal fitting 8 and the fixing region is connected to the external device). The uncured resin 100A is filled so that the region reaching the connection side region (hereinafter referred to as an exposed region) is exposed from the resin 100A.

  Here, since the entire combination 10 of the coil 2A and the magnetic core 3 is fixed in advance by the bonding layer 42 (FIG. 3) provided on the mounting surface of the bottom plate portion 40, filling of the uncured resin 100A is performed. At this time, the position in the case 4A in the combined body 10 is not displaced, and the filling workability is excellent.

(3) Curing Step In this step, hot air is blown onto the resin filler 10A to cure the uncured resin 100A to obtain the resin 100. For curing the uncured resin 100A, for example, a hot-air type curing tank (constant temperature tank) can be suitably used.

  An example of a hot air type curing tank is shown in FIG. The curing tank 90 includes a container main body 91 having a heat insulating function, a heat source 92 such as a heater installed in the container main body 91, a fan 93 that sends heat from the heat source 92 into the container main body 91 as hot air, It includes a backing plate 94 such as a punching metal or a wire mesh that diffuses hot air into the container main body 91. By appropriately adjusting the control conditions such as the energization current to the heat source 92 and the air volume by the fan 93, the inside of the curing tank 90 can be brought to a desired temperature and can be kept at a constant temperature. Therefore, the control conditions are adjusted as appropriate according to the curing temperature of the resin 100 used.

  And in the manufacturing method of the reactor of embodiment, when manufacturing the reactor 1A in which a part of attachment member is embed | buried in the resin 100 and the remainder is exposed from the resin 100, at least the exposed region of the attachment member in the resin filling 10A Is covered with a heat transfer cover 95 to cure the uncured resin 100A. FIG. 5 shows a state in which the entire resin filling 10 </ b> A is covered with a heat transfer cover 95. Here, the attachment member is the terminal fitting 8 having a higher thermal conductivity than the constituent material of the resin 100 and the case 4 </ b> A, and the exposed region of the attachment member is the exposed region of the terminal fitting 8.

  The heat transfer cover 95 is made of a material that does not ignite, soften or melt at the curing temperature of the resin 100A, relaxes the hot air sent from the fan 93, and allows the heat conduction into the cover 95 to some extent. Is available. The heat transfer cover 95 has a thermal conductivity capable of at least setting the temperature in the cover 95 to a predetermined curing temperature, and preferably the time required to reach the predetermined curing temperature is not excessively long. Is available.

  The constituent material of the heat transfer cover 95 preferably has pores. Examples of the material having pores include a woven fabric or a nonwoven fabric composed of fibers. The thickness and material of the woven or non-woven fiber (organic material such as cotton, wool, synthetic fiber, or inorganic material such as metal) can be selected as appropriate. Further, in the case of a woven fabric, the opening and weaving method can be selected as appropriate, and in the case of a non-woven fabric, the basis weight can be appropriately selected. Since the woven fabric and the nonwoven fabric are rich in flexibility, when the hot air is received, the woven fabric or the non-woven fabric itself is deformed, and the hot air transmitted through the fabric can be mitigated. In addition, since the woven fabric and the nonwoven fabric have pores, the heat of the hot air can be directly transferred into the fabric to some extent as compared to a metal foil that does not substantially have pores. As a result, the time required for the temperature in the cloth to reach the predetermined curing temperature does not become long, or the time required can be made substantially the same as when the heat transfer cover 95 is not provided. Therefore, in consideration of industrial production, a woven fabric made of fibers can be suitably used for the heat transfer cover 95. As a more specific constituent material, a plain woven fabric made of cotton having a fiber diameter (wire diameter) of about 1 μm to 60 μm can be mentioned.

  The heat transfer cover 95 is sized to cover at least the exposed region of the attached member (here, the exposed region of the terminal fitting 8). As shown in FIG. 5, when the entire resin filling 10 </ b> A is covered with the heat transfer cover 95, the heat transfer cover 95 can be easily arranged and the workability is excellent. Therefore, the heat transfer cover 95 can have a size capable of covering the entire resin filler 10A. Further, by covering the entire resin filling 10A with the heat transfer cover 95, it is easy to make the temperature rising state of the entire resin filling 10A uniform, and the uncured resin 100A can be cured more uniformly.

  In addition, about the contact plate 94 arrange | positioned in the hardening tank 90, in the case of a metal mesh, by changing the wire diameter of a metal wire, an opening, a mesh, in the case of punching metal, a hole diameter, the number of holes, etc., By using a fine metal mesh or a punching metal with a small hole diameter or a small number of holes, there is an effect of alleviating the hot air from the fan 93 to some extent. However, it is considered that the hot air from the fan 93 can be more effectively mitigated by directly covering the specific portion of the resin filling 10 </ b> A (exposed region of the attached member) with the heat transfer cover 95.

  By covering at least a part of the resin filling 10A with the heat transfer cover 95, the resin filling 10A is stored in a hot-air type curing tank 90 and held at a predetermined curing temperature for a predetermined time to cure the uncured resin 100A. , Reactor 1A is obtained.

(Use)
Reactor 1A has applications where current-carrying conditions are, for example, maximum current (direct current): about 100A to 1000A, average voltage: about 100V to 1000V, operating frequency: about 5kHz to 100kHz, typically an electric vehicle, a hybrid vehicle, etc. It can utilize suitably for the component of the vehicle-mounted power converter device.

(Main effect)
Reactor 1 </ b> A is manufactured by the method for manufacturing a reactor according to the embodiment, so that variation in internal stress is small throughout resin 100. Therefore, even when the reactor 1A is used for a long period of time, the resin 100 is hardly cracked and is not easily cracked, so that it is expected to have a long life. In particular, even when the reactor 1A is used for a long period of time, cracks starting from the contact area with the accessory member in the resin 100 and the area in the vicinity thereof hardly occur or do not substantially occur. Further, the reactor 1A has little or substantially no heat sink, particularly in the contact area with the accessory member in the resin 100 and the area in the vicinity thereof, and is excellent in appearance.

  The manufacturing method of the reactor of the embodiment can reduce or substantially eliminate the presence of a region where the temperature is locally increased in the process of raising the temperature to a predetermined curing temperature in the resin curing step. Therefore, the temperature rise state of the uncured resin 100A can be made uniform, and the arrival time to the curing temperature can be easily made uniform throughout the resin 100A. As a result, the manufacturing method of the reactor of the embodiment can be cured uniformly over the entire resin 100A. The obtained reactor 1A is expected to be hard to crack in the resin 100 over a long period of time as described above.

[Test Example 1]
A combination comprising a coil and a magnetic core was housed in a case, filled with uncured resin, and the temperature change of the resin was examined when the resin was cured using a hot-air type curing tank.

  In this test, the thing of the structure similar to the reactor 1A shown in FIG. 1 was produced. That is, a coil including a pair of coil elements in which a coated rectangular wire is edgewise wound, an annular magnetic core mainly composed of a core piece made of a soft magnetic material, and a case housing a combination of the coil and the magnetic core; A reactor comprising a resin filled in the case and a tin-plated copper terminal fitting partly fixed to the case and another part embedded in the resin was produced. As the case, a case having an aluminum alloy bottom plate portion on which the assembly is placed and a PPS resin side wall portion standing from the bottom plate portion was used.

  As described above, prepare an assembly in which the assembly and a part of the terminal fitting are housed in the case, fill the case with uncured resin, and part of the terminal fitting is immersed in the uncured resin. Then, a resin filling was prepared in which the remainder was exposed from this resin. As the resin to be filled in the case, an epoxy resin having a curing temperature of about 80 ° C. to 160 ° C. was used.

  Sample No. In No. 1, the entire resin filling was covered with a heat transfer cover made of cotton woven fabric (FIG. 5), and then stored in a hot air type curing tank to cure the resin. As the hot-air type curing tank, a commercially available product or a known one can be used.

  Sample No. In 100, without covering with the heat transfer cover, the resin filling was directly stored in a hot air type curing tank to cure the resin. The curing tank is a sample no. The same as 1 was used.

  The set temperature of the curing tank is 120 ° C. 1, No. 1 Each of the 100 resin fillings was stored in a curing tank and held for 3 hours. With respect to the resin provided in the resin filling, a plurality of points were measured, and the change in temperature during the above holding time: 0 minutes to 180 minutes was examined. FIG. 1 is a graph of the temperature change of No. 1, the horizontal axis indicates elapsed time (minutes), and the vertical axis indicates temperature (° C.). FIG. It is a graph of 100 temperature changes, an abscissa indicates elapsed time (minutes), and an ordinate indicates temperature (° C.). In the graphs of FIGS. 6 and 7, the temperature change from 0 minutes to 170 minutes is shown.

  Here, Sample No. 1, No. 1 For 100 resin fillings, temperature sensors were previously arranged at each point so that the temperature at a plurality of different points in the resin could be measured. As shown in the plan view of FIG. 2, a point P1 on the upper side of the connecting portion 812 of the terminal fitting 8 attached on the left side, a lower point (not shown) near the bottom plate portion as viewed from this point P1, the coil element 2a , 2b, the point P3 on one coil element 2a, the point P4 between the two terminal fittings 8 and 8, and the four corners of the rectangular opening of the case 4A, away from the terminal fitting 8. A total of 8 temperatures of three points P5, P6 and P7, and a sample No. 1 shows the temperature in the heat transfer cover, sample No. In 100, the temperature in the curing tank was measured. In FIG. 6, the temperature of the points P1-P3 and the atmospheric temperature P in the heat transfer cover are shown. In FIG. 7, the temperature of the points P1-P3 and the atmospheric temperature P0 in a hardening tank are shown.

  As shown in FIG. 7, it can be seen that the temperature P0 in the curing tank reaches the set temperature of about 120 ° C. immediately after the start of the holding time, and thereafter is kept constant. In addition, at three points P1 to P3, it can be seen that after about 120 minutes, the temperature reached the same level as that in the curing tank, that is, about 120 ° C. However, in the points P1 to P3, the temperature rise state until reaching this reached temperature (set temperature) is different. Specifically, the points P2 and P3 near the coil are in substantially the same temperature rising state (in FIG. 7, the graphs of the points P2 and P3 overlap). For example, the time required to reach 100 ° C. is about 40 minutes at both points P2 and P3. Although not shown, other points P4 to P7 and the like also draw almost the same locus (graph) as the points P2 and P3. However, at the point P1 in the vicinity of the connecting portion 812 of the terminal fitting 8, the temperature increase rate is faster than at the point P2. Specifically, at the point P1, the time required to reach 100 ° C. is about 30 minutes. That is, at the point P1, it can be said that the temperature is higher than the other parts in the temperature raising process until the predetermined curing temperature is reached. Further, at the point P1, it can be said that it has reached in a short time due to the curing temperature as compared with other portions, and the start of curing is accelerated. Actually, the sample No. obtained after the curing. In the reactor of 100, thermal sink marks were seen more in the region near the connecting portion 812 of the terminal fitting 8 in the resin than in other regions. This is considered to support that the area | region of the connection part 812 vicinity in resin hardened | cured before the other area | region.

  On the other hand, as shown in FIG. 6, when the heat transfer cover is used, the temperature P in the heat transfer cover is slightly lower than the temperature in the curing tank, but reaches about 120 ° C. after about 120 minutes, and thereafter It can be seen that it is held constant. In addition, it can be seen that the three points P1 to P3 also reach a temperature equivalent to the temperature in the heat transfer cover, that is, a little less than 120 ° C., approximately 120 minutes later. And about the points P1-P3, it turns out that the temperature rising state until it becomes this ultimate temperature (setting temperature) is substantially equal. Specifically, at points P2 and P3 near the coil, for example, the time required to reach 100 ° C. is about 60 minutes, and other points P4 to P7 not shown are also points P2 and P3. Draw roughly the same trajectory (graph). In addition, at the point P1 in the vicinity of the connecting portion 812 of the terminal fitting 8, the time required to reach 100 ° C. is less than 60 minutes, and it can be seen that the difference in the heating rate is small compared to the point P2 and the like. That is, sample no. 1, it can be said that in each part of the uncured resin, the temperature raising process until reaching a predetermined curing temperature is substantially equal. Moreover, it can be said that the hardening start is performed similarly over the whole uncured resin. Actually, the sample No. obtained after the curing. In the reactor No. 1, sample No. Unlike 100, the region near the connecting portion 812 of the terminal fitting 8 in the resin 100 does not have much heat sink compared with other regions, and has a uniform appearance over the entire resin 100. It was. This is considered to support that the uncured resin 100A can be uniformly cured.

  Further, it can be seen from the test results that the heat transfer cover preferably relaxes hot air such as a woven fabric of fibers such as cotton and allows heat conduction to some extent.

  Hereinafter, other usable configurations are listed for each component of the reactor 1A.

Coil The winding 2w forming the coil 2A is preferably a coated wire having an insulating coating made of an insulating material (typically polyamideimide) on the outer circumference of a conductor made of a conductive material such as copper, aluminum, or an alloy thereof. Available (Figs. 3 and 4). The conductor is typically a round wire in addition to a rectangular wire. As in this example, when an edgewise coil is formed by using a (covered) rectangular wire for the winding 2w, a coil having a higher space factor than that in the case of using a round wire can be easily formed. Moreover, when both the coil elements 2a and 2b are edgewise coils, it is easy to secure a wide area in the coil 2A that is disposed close to the bottom plate portion 40, and it is easy to improve heat dissipation. The end face shapes of the coil elements 2a and 2b can be changed as appropriate, such as an annular shape, in addition to the above-described rectangular tube shape.

-Magnetic core The shape and number of each core piece and the gap material 31g which comprise the magnetic core 3 can be selected suitably (FIG. 4). In the first embodiment, the inner core portion 31 is a rectangular parallelepiped shape, and the outer core portion 32 is a deformed columnar body having a convex shape (dome shape) on its end surface. 32 may have a rectangular parallelepiped shape (FIG. 8 to be described later). Examples of the soft magnetic material that is the main component of the core piece include metals such as iron, iron alloys, and alloys containing rare earth elements, and nonmetals such as ferrite. As the core piece, a molded body using the soft magnetic powder made of the soft magnetic material or a laminated body in which a plurality of magnetic thin plates having an insulating coating (for example, an electromagnetic steel plate typified by a silicon steel plate) are stacked can be used. As for the said molded object, the composite material containing a sintered compact, soft magnetic powder, and resin other than a compacting body (powder magnetic core) is mentioned. Even if the composite material has a complicated three-dimensional shape by using injection molding or the like, it can be easily molded. The magnetic core 3 can be in a form without the gap material 31g or a form with an air gap.

  In particular, in the reactor 1A, the surface (the lower surface in FIG. 3) of the outer core portions 32, 32 of the magnetic core 3 is flush with the surface (the lower surface in FIG. 3) of the coil 2A on the bottom plate portion 40 side. Thus, the outer core portions 32 and 32 are also bonded to the bottom plate portion 40 by the bonding layer 42. Therefore, the heat of the magnetic core 3 can also be transmitted to the bottom plate portion 40 favorably, and the reactor 1A is excellent in heat dissipation.

Core parts The core parts 5A and 5B will be described in more detail with reference to FIG. The frame plate portion 52 includes an end surface covering portion 51e that covers a part of one end surface 31e of one inner core portion 31, and a through hole 53A (53B) through which the other inner core portion 31 is inserted. The end portion 517A of the peripheral surface covering portion 51o of one core component 5A is inserted into the through hole 53B of the other core component 5B, and the end portion 517B of the peripheral surface covering portion 51o of the other core component 5B is inserted into the one core component 5A. The core parts 5A and 5B can be made into an integral assembly connected by the frame plate parts 52 and 52 by being inserted into the through hole 53A. One end surface 31e of the inner core portion 31 and the inner end surface 32e of the outer core portion 32 can be joined by filling the through hole provided in the end surface covering portion 51e with an adhesive. The end face covering portion 51e and the adhesive function as a gap. The other end surface 31e of the inner core portion 31 is exposed from the through holes 53A and 53B, and can come into contact with the inner end surface 32e of the outer core portion 32.

  In addition, in the core components 5A and 5B, a partition 56 that is erected on the surface of the frame plate portion 52 on the coil 2A side and is inserted between the coil elements 2a and 2b to insulate the coil elements 2a and 2b, and a frame plate The base 52 extends outward from the surface on the outer core portion 32 side in the portion 52 (toward the outer core portion 32 side) and is interposed between the coupling portion 2r of the coil 2A and the upper end surface of the outer core portion 32. 54 and a projection 58 that projects from the surface on the outer core portion 32 side and positions the outer core portion 32.

-Insulator It can be set as the form provided with an insulator (not shown) separately instead of the core components 5A and 5B. This form can also improve the insulation between the coil 2A and the magnetic core 3, and can increase the certainty of positioning of both. The insulator includes, for example, a peripheral wall portion disposed on the outer periphery of the inner core portion 31, and a pair of frame plates interposed between the end surfaces of the coil elements 2a and 2b and the inner end surface 32e of the outer core portion 32. Is mentioned. Examples of the peripheral wall part include a form that is a cylindrical body, a form that is arranged on the outer periphery of the inner core part 31 by combining members having a cross-sectional shape. It can also be set as the form by which at least one part of the surrounding wall part and one frame board were integrally shape | molded. Examples of the frame plate include a B-shaped plate material having two through holes through which both inner core portions 31 and 31 are inserted. FIG. 8 to be described later shows a form including an insulator.

  The insulating resin of the core parts 5A and 5B and the constituent material of the insulator are, for example, PPS resin, polytetrafluoroethylene (PTFE) resin, liquid crystal polymer (LCP), nylon 6, nylon 66, polybutylene terephthalate (PBT) resin. And other thermoplastic resins. In addition, the combination body 10 can be made into the form which is not provided with the said insulating resin and an insulator.

-Case Non-metals, such as a metal and resin, are mentioned as a constituent material of case 4A. Specific examples of the metal include aluminum and alloys thereof, magnesium (156 W · m / K) and alloys thereof, iron (80.3 W / m · K), austenitic stainless steel, and the like. Many of these metals have a lower thermal conductivity than copper or the like constituting the terminal fitting 8. Aluminum or an alloy thereof can be a case 4A that is lightweight and excellent in heat dissipation. Magnesium or an alloy thereof can be made into a case 4A that is lightweight and excellent in vibration damping. Stainless steel can be used as the case 4A having excellent mechanical strength. In particular, metals tend to be superior in strength and rigidity compared to resins, and it is possible to construct a reactor 1A that is easy to suppress and reduce vibrations and noises and is excellent in heat dissipation. In addition, the metal case 4A can be expected to have a shielding effect. Considering heat dissipation and strength against placement of the combined body 10 of the coil 2A and the magnetic core 3, the bottom plate portion 40 is preferably made of metal, and the thickness thereof is about 2 mm or more and 5 mm or less.

  On the other hand, examples of the resin constituting the case 4A include PPS resin, PBT resin, urethane resin, and acrylonitrile-butadiene-styrene (ABS) resin. The resin can be a case 4A that is lightweight and excellent in electrical insulation.

  In the form in which the bottom plate part 40 and the side wall part 41 can be disassembled as in the case 4A of the first embodiment, both can be made of the same kind of material or different kinds of materials. A bottom part and a wall part can be formed integrally as in a case 4B of the second embodiment described later. In this case, the case 4B is entirely made of a uniform material and has a uniform thermal conductivity.

  The external shape of the baseplate part 40 and the side wall part 41 can be selected suitably. As described above, here, the bottom plate portion 40 has the mounting portion 400, and the side wall portion 41 has the mounting portion 411. When the case 4A is assembled, the bottom plate portion 40 and the side wall are arranged so that these mounting portions 400, 411 overlap. A portion 41 is formed (FIGS. 1 to 3). Bolt holes 400h and 411h through which tightening members (bolts, not shown) for fixing to the installation target are inserted are provided in the attachment portions 400 and 411, respectively. The shape, the number, and the like of the attachment portions 400 and 411 can be selected as appropriate. For example, one of the attachment portions 400 and 411 can be omitted. When the side wall portion 41 is made of resin, the bolt hole 411h is excellent in strength when configured by a metal tube.

  Here, the connection between the bottom plate portion 40 and the side wall portion 41 uses the bolt 4b and the adhesive in combination, but only one of them can be used. When the bottom plate portion 40 and the side wall portion 41 are integrated with an adhesive, the adhesive can be sealed between them to prevent leakage of the uncured resin 100A, and a sealing material such as packing can be omitted. In the case where the bottom plate portion 40 and the side wall portion 41 are integrated only by the bolt 4b, if a packing (not shown) is provided between the bottom plate portion 40 and the side wall portion 41, the bottom plate portion is filled with the uncured resin 100A. The uncured resin 100 </ b> A can be prevented from leaking from the gap between the wall 40 and the side wall 41.

  As the bonding layer 42, typically, a resin having heat resistance to such an extent that the bonding layer 42 does not soften with respect to the highest temperature achieved when the reactor 1A is used can be suitably used. In particular, when the bottom plate portion 40 is made of metal, the constituent material of the bonding layer 42 is preferably an insulating resin in order to improve the insulation with the coil 2A. As the specific resin, a thermosetting resin such as an epoxy resin, a silicone resin, or an unsaturated polyester, or a thermoplastic insulating resin such as a PPS resin or LCP can be suitably used for the bonding layer 42. If this insulating resin contains the ceramic filler described above, the heat dissipation can be improved. The thermal conductivity of the bonding layer 42 is 0.1 W / m · K or more, further 0.15 W / m · K or more, 0.5 W / m · K or more, 1 W / m · K or more, particularly 2.0 W / m. -It is preferable that it is K or more because of excellent thermal conductivity. For example, when an epoxy adhesive containing a filler made of alumina is used, the bonding layer 42 having a thermal conductivity of 3 W / m · K or more can be obtained. The thickness (after curing) of the bonding layer 42 is, for example, 1 mm or less, and further 0.5 mm or less.

-Other components Reactor 1A can be made into the form provided with the lid | cover (not shown) which covers the opening part of case 4A. By having the lid, it is expected that the resin 100 can be protected from the external environment and noise can be further reduced.

  Reactor 1A can be configured to include a sensor that measures the physical quantity of the reactor. Examples of the sensor include a temperature sensor, a current sensor, a voltage sensor, a magnetic flux sensor, and an acceleration sensor that can measure the vibration of the reactor.

[Embodiment 2]
In the reactor 1A of the first embodiment, the form in which the attached member is the terminal fitting 8 connected to the end of the winding 2w forming the coil 2A has been described. As other accessory members, for example, a heat radiating member may be mentioned. Hereinafter, the form provided with a heat radiating member is demonstrated.

  The reactor 1B of the second embodiment shown in FIG. 8 has the same basic configuration as that of the first embodiment, and a case 4B that houses the coil 2B, the magnetic core 3, and the combined body 10 of the coil 2B and the magnetic core 3. And a resin 100 that fills the case 4B and seals the combined body 10, and does not include a terminal fitting. In particular, in the reactor 1B, the coil elements 2a and 2b included in the coil 2B are formed by different windings 2wa and 2wb, respectively, and includes a connecting member 2R that electrically connects one end portions of the windings 2wa and 2wb. The connecting member 2R shown in this example also functions as a heat radiating member.

  The connecting member 2R is made of a material having excellent conductivity such as copper or an alloy thereof. Specifically, a flat belt-shaped main body is provided, and one end side region of the main body is a connection region with one end of the winding 2wa, and the other end side region is a connection region with one end of the winding 2wb. For connection between the windings 2wa and 2wb and the connecting member 2R, welding such as TIG welding, pressure bonding, soldering, or the like can be used.

  A plurality of flat plate pieces are erected in parallel at an intermediate portion of the main body of the connecting member 2R. These flat plate pieces constitute the fin portion 2f. Here, as shown in FIG. 8, a part of the fin portion 2 f (connection side region with the flat belt-like main body) is embedded in the resin 100, and the remaining portion is exposed from the resin 100.

  For the purpose of improving the heat dissipation and increasing the contact area with the resin 100, the fin portion 2f is provided with a surface area as large as possible, for example, a wide plate material, more specifically, the windings 2wa and 2wb. It is preferable to use a plate material having a width wider than the width. However, in this case, when the uncured resin is cured using hot air, the wide fin portion 2f is easily subjected to the hot air, and the contact region with the fin portion 2f in the uncured resin and the region in the vicinity thereof are high temperature. It becomes easy to become. In particular, the fin portion 2f is made of a material having excellent thermal conductivity, such as copper, specifically, a material having better thermal conductivity than the constituent material of the resin 100 or the case 4B (for example, an aluminum alloy), so that it is uncured. The contact region of the resin with the fin portion 2f and the region in the vicinity thereof are likely to become higher in temperature. Therefore, as described in the first embodiment, curing is performed with the heat transfer cover 95 (FIG. 5) covering at least the fin portion 2 f and the vicinity thereof. By carrying out like this, also in the reactor 1B of Embodiment 2, uncured resin can be hardened | cured uniformly. Further, the obtained reactor 1B has a small variation in internal stress of the resin 100 and is difficult to crack, and has few surface defects such as heat sinks.

  Even when the connecting member 2R does not have the fin portion 2f, in a form in which a part of the connecting member 2R is embedded in the resin 100 and the remaining portion is exposed from the 100, the connecting member 2R is a winding. It is considered that hot air is easily received by being wider than the width or relatively large. Then, the contact portion with the connecting member 2R in the uncured resin and the vicinity thereof are likely to become high temperature. Therefore, as described in the first embodiment, it is preferable that the reactor of this embodiment is cured in a state where the exposed region of the connecting member 2R and the vicinity thereof are covered by the heat transfer cover 95 (FIG. 5).

  As another heat radiating member, for example, a heat radiating plate (not shown) having a portion interposed between the coil elements 2a and 2b can be cited. The heat radiating plate is arranged so that one end edge thereof is in contact with the bottom plate portion 40, the region on the other end edge side is exposed from the resin 100, and the intermediate portion is a region interposed between the coil elements 2 a and 2 b. Such a heat radiating plate may be fixed to the bottom plate portion 40 with bolts, an adhesive, or the like, and may be erected from the bottom plate portion 40 toward the opening side of the case 4B.

  When the heat radiating plate is an independent member that can be attached to and detached from the bottom plate portion 40, a material different from that of the bottom plate portion 40 can be used. For example, with respect to a case made of an aluminum alloy, the constituent material of the heat sink can be a material that is more excellent in heat dissipation, such as copper, an alloy thereof, silver, an alloy thereof, or the like. When the heat radiating plate is made of metal, an insulating layer or the like can be formed in order to enhance insulation with the coil elements 2a and 2b. Alternatively, as the constituent material of the heat sink, for example, various high thermal conductive ceramics described in the section of the ceramic filler can be used. Many ceramic heat sinks are excellent in insulation, and can function as an insulating material between the coil elements 2a and 2b. In particular, when the case is made of resin, the ceramic is superior in thermal conductivity to the resin 100 and the case, so that the ceramic plate can function well as a heat sink.

  As another heat dissipation member, for example, a form in which a part of the magnetic core 3 has a heat dissipation function can be cited. Here, for example, when the outer core portion 32 of the magnetic core 3 is made of the above-described composite material, even if it has a complicated three-dimensional shape by injection molding or the like, it can be easily molded. A form in which a protrusion (fin part, not shown) that protrudes from the dome-shaped surface (here, a dome-shaped surface) toward the opening side of the case 4B is formed, and a part of the fin part is exposed from the resin 100 is exemplified. In this embodiment, since the fin portion is mainly composed of a soft magnetic material, the fin portion is superior in thermal conductivity to the resin 100, and the case 4B is composed of a material having poor thermal conductivity such as PPS resin. If it is, it can function well as a heat dissipation member. However, it can be said that the contact region with the fin portion in the resin 100 and the region in the vicinity thereof are regions where the fin portion is easily subjected to hot air, and is likely to become high temperature during curing. Therefore, this form can also harden uncured resin uniformly by utilizing the manufacturing method of a reactor of an embodiment. In addition, the case of this form does not have a collar part and has a wide opening like the case 4B shown in FIG. 8 so that the exposed region from the resin 100 in the fin part can sufficiently contact the atmosphere. preferable. Further, if a metal foil (such as a copper foil or an aluminum foil) having excellent thermal conductivity is attached to an exposed region from the resin 100 in the fin portion, the heat dissipation can be further improved.

  In the embodiment including the heat dissipating member having the region embedded in the resin 100 described above, the terminal fitting can be configured not to have the region embedded in the resin 100.

[Embodiment 3]
In the first and second embodiments, the embodiment including the pair of coil elements 2a and 2b has been described. In addition, a coil can be made into the form (not shown) provided with only one coil element. In this embodiment, the magnetic core 3 is disposed so as to cover a columnar inner core portion disposed in the cylindrical coil element, each end surface of the inner core portion, and at least a part of each end surface of the coil element. It is good to provide the outer core part which has a part and the part which connects between the both end surfaces of an inner core part.

[Embodiment 4]
The reactors 1A, 1B and the like of the first to third embodiments can be used for, for example, a component part of a converter mounted on a vehicle or the like, or a component part of a power conversion device including this converter.

  For example, a vehicle 1200 such as a hybrid vehicle or an electric vehicle is used for traveling by being driven by a main battery 1210, a power converter 1100 connected to the main battery 1210, and power supplied from the main battery 1210 as shown in FIG. The motor (load) 1220 is provided. The motor 1220 is typically a three-phase AC motor, which drives the wheel 1250 when traveling and functions as a generator during regeneration. In the case of a hybrid vehicle, vehicle 1200 includes an engine in addition to motor 1220. In addition, in FIG. 9, although an inlet is shown as a charge location of the vehicle 1200, it can be set as the form provided with a plug.

  Power conversion device 1100 includes converter 1110 connected to main battery 1210 and inverter 1120 connected to converter 1110 and performing mutual conversion between direct current and alternating current. Converter 1110 shown in this example boosts the DC voltage (input voltage) of main battery 1210 of about 200V to 300V to about 400V to 700V and supplies power to inverter 1120 when vehicle 1200 is traveling. In addition, converter 1110 steps down DC voltage (input voltage) output from motor 1220 via inverter 1120 to DC voltage suitable for main battery 1210 during regeneration, and causes main battery 1210 to be charged. The inverter 1120 converts the direct current boosted by the converter 1110 into a predetermined alternating current when the vehicle 1200 is running, and supplies the motor 1220 with electric power. During regeneration, the alternating current output from the motor 1220 is converted into direct current and output to the converter 1110. doing.

  As shown in FIG. 10, the converter 1110 includes a plurality of switching elements 1111, a drive circuit 1112 that controls the operation of the switching elements 1111, and a reactor L, and converts input voltage by ON / OFF repetition (switching operation). (In this case, step-up / down pressure) is performed. For the switching element 1111, a power device such as a field effect transistor (FET) or an insulated gate bipolar transistor (IGBT) is used. The reactor L has the function of smoothing the change when the current is going to increase or decrease by the switching operation by utilizing the property of the coil that prevents the change of the current to flow through the circuit. As this reactor L, the reactor of the said Embodiment 1-3 is provided. By providing the reactor 1A and the like in which the resin 100 is uniformly cured, the power conversion device 1100 and the converter 1110 have a long life because the resin 100 hardly breaks with time.

  Vehicle 1200 is connected to converter 1110, power supply converter 1150 connected to main battery 1210, sub-battery 1230 serving as a power source for auxiliary machinery 1240, and main battery 1210. Auxiliary power supply converter 1160 for converting high voltage to low voltage is provided. The converter 1110 typically performs DC-DC conversion, while the power supply device converter 1150 and the auxiliary power supply converter 1160 perform AC-DC conversion. Some power supply device converters 1150 perform DC-DC conversion. The reactor of the power supply device converter 1150 and the auxiliary power supply converter 1160 has the same configuration as that of the reactor 1A of the first to third embodiments, and a reactor whose size and shape are appropriately changed can be used. Further, the reactor 1A of the first to third embodiments can be used for a converter that performs conversion of input power, that is, a converter that performs only step-up or a converter that performs only step-down.

  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 suitably used as a component part of a power converter. The manufacturing method of the reactor of this invention can be utilized suitably for manufacture of the said reactor.

1A, 1B reactor 10 combination 10A resin filling 100 resin 100A uncured resin 2A, 2B coil 2a, 2b coil element 2r connecting part 2R connecting member 2f fin part 2w, 2wa, 2wb winding 3 magnetic core 31 inner core part 31e End face 31m Core piece 31g Gap material 32 Outer core part 32e Inner end face 4A, 4B Case 40 Bottom plate part 41 Side wall part 42 Joining layer 40h, 41h Connection hole 4b Connection bolt 400,411 Installation part 400h, 411h Bolt hole 410 413 Wall part 415 Clamping base part 416 Insertion hole 417 Positioning protrusion 419 Bolt 5A, 5B Core part 51o Peripheral surface covering part 51e End surface covering part 517A, 517B End part 52 Frame plate part 53A, 53B Through hole 54 Base 56 Partition 58 Projection 8 Terminal fitting 81 Joint DESCRIPTION OF SYMBOLS 10 Inclined piece 812 Connection part 85 Fixing hole 86 Latching part 87 Positioning notch 87h Positioning hole 90 Curing tank 91 Container body 92 Heat source 93 Fan 94 Cover plate 95 Heat transfer cover 1100 Power converter 1110 Converter 1111 Switching element 1112 Drive circuit L Reactor 1120 Inverter 1150 Power Supply Converter 1160 Auxiliary Power Supply Converter 1200 Vehicle 1210 Main Battery 1220 Motor 1230 Sub Battery 1240 Auxiliary Equipment 1250 Wheel

Claims (10)

A preparatory step of preparing a combination in which a combination including a coil and a magnetic core and a part of an attached member are housed in a case;
Filling the case with an uncured resin, a part of the attachment member is immersed in the resin, and a filling step in which the remainder of the attachment member is exposed from the resin;
And a curing step of curing the uncured resin by blowing hot air on the resin filling,
In the curing step, the reactor is cured in a state where at least an exposed area of the accessory member exposed from the resin is covered with a heat transfer cover that relaxes the hot air.   The reactor manufacturing method according to claim 1, wherein the heat transfer cover is made of cloth.   The method for manufacturing a reactor according to claim 1, wherein the side wall portion of the case is made of resin.   The method for manufacturing a reactor according to any one of claims 1 to 3, wherein the attachment member is a terminal fitting connected to an end portion of a winding forming the coil.   The reactor manufacturing method according to claim 1, wherein the exposed region of the attachment member has a portion wider than a width of a winding forming the coil.   The method for manufacturing a reactor according to any one of claims 1 to 5, wherein, in the curing step, curing is performed in a state where the entire resin filling is covered with the heat transfer cover.   The method for manufacturing a reactor according to any one of claims 1 to 6, wherein the attachment member is made of a material having a higher thermal conductivity than a constituent material of the case.   A reactor manufactured by the method for manufacturing a reactor according to claim 1.   A converter comprising the reactor according to claim 8.   A power converter device comprising the converter according to claim 9.

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