Patent Grant
12073975
This application is a national phase of PCT application No. PCT/JP2020/000202, filed on 7 Jan. 2020, which claims priority from Japanese patent application No. 2019-002997, filed on 10 Jan. 2019, all of which are incorporated herein by reference.
The present disclosure relates to a reactor.
Patent Document 1 discloses a reactor including a coil, a magnetic core, a case for accommodating an assembly of the coil and the magnetic core and a sealing resin for covering the outer periphery of the assembly. In Patent Document 1, an introduction path for the sealing resin is integrally formed in a constituent member of the reactor to fill the sealing resin from a bottom side of the case toward an opening side of the case. A side wall portion of the case surrounding the outer periphery of the assembly is illustrated as the constituent member forming the introduction path.
A first reactor according to the present disclosure is provided with a coil including a pair of winding portions arranged in parallel, a magnetic core to be arranged inside and outside the winding portions, a case for accommodating an assembly including the coil and the magnetic core, and a sealing resin portion to be filled into the case, wherein the case includes a bottom plate portion, the assembly being placed on the bottom plate portion, a side wall portion constituted by a rectangular frame body for surrounding the assembly, and an opening provided on a side opposite to the bottom plate portion, the pair of winding portions are so arranged that a parallel direction is orthogonal to the bottom plate portion, the side wall portion includes a pair of short side portions and a pair of long side portions, and the short side portion or the long side portion includes a groove portion continuously provided from the opening side toward the bottom plate portion side and open inward of the case.
A second reactor according to the present disclosure is provided with a coil including a pair of winding portions arranged in parallel, a magnetic core to be arranged inside and outside the winding portions, a case for accommodating an assembly including the coil and the magnetic core, and a sealing resin portion to be filled into the case, wherein the case includes a bottom plate portion, the assembly being placed on the bottom plate portion, a side wall portion constituted by a rectangular frame body for surrounding the assembly, and an opening provided on a side opposite to the bottom plate portion, the pair of winding portions are so arranged that axes thereof are orthogonal to the bottom plate portion, the side wall portion includes a pair of short side portions and a pair of long side portions, and the short side portion or the long side portion includes a groove portion continuously provided from the opening side toward the bottom plate portion side and open inward of the case.
It is desired to further miniaturize a reactor. The miniaturization of the reactor here means a small installation area of the reactor and a small interval between an assembly and a case. It is also desired to further improve the heat dissipation of the reactor. The reactor described in Patent Document 1 has room for improvement in improving miniaturization and heat dissipation.
Accordingly, one object of the present disclosure is to provide a reactor small in size and excellent in heat dissipation.
The reactor of the present disclosure is small in size and excellent in heat dissipation.
First, contents of embodiments of the present disclosure are listed and described.
(1) A first reactor according to an embodiment of the present disclosure is provided with a coil including a pair of winding portions arranged in parallel, a magnetic core to be arranged inside and outside the winding portions, a case for accommodating an assembly including the coil and the magnetic core, and a sealing resin portion to be filled into the case, wherein the case includes a bottom plate portion, the assembly being placed on the bottom plate portion, a side wall portion constituted by a rectangular frame body for surrounding the assembly, and an opening provided on a side opposite to the bottom plate portion, the pair of winding portions are so arranged that a parallel direction is orthogonal to the bottom plate portion, the side wall portion includes a pair of short side portions and a pair of long side portions, and the short side portion or the long side portion includes a groove portion continuously provided from the opening side toward the bottom plate portion side and open inward of the case.
In the reactor of the present disclosure, the coil in the case is so arranged that the parallel direction of the pair of winding portions is orthogonal to the bottom plate portion. This arrangement mode is called a vertically stacked type. On the other hand, in the reactor described in Patent Document 1, the coil in the case is so arranged that the parallel direction of the pair of winding portions is parallel to the bottom plate portion. This arrangement mode is called a horizontally placed type.
The reactor of the present disclosure including the coil of the vertically stacked type can reduce an installation area with respect to the bottom plate portion of the case as compared to a reactor including a coil of the horizontally placed type. This is because a length of the assembly along a direction orthogonal to both the parallel direction of the pair of winding portions and axial directions of the both winding portions is generally shorter than a length of the assembly along the parallel direction of the pair of winding portions. Thus, the reactor of the present disclosure is thin and small in size. Particularly, the reactor of the present disclosure including the coil of the vertically stacked type can reduce the installation area with respect to the bottom plate portion of the case as compared to a reactor including a coil of an upright type to be described later if the length of the assembly along the parallel direction of the pair of winding portions is longer than a length of the assembly along the axial directions of the winding portions.
The reactor of the present disclosure including the coil of the vertically stacked type is excellent in heat dissipation as compared to the reactor including the coil of the horizontally placed type. This is because the coil of the vertically stacked type can increase facing areas of the winding portions and the case and easily releases heat generated in the assembly to the case as compared to the coil of the horizontally placed type.
By providing the groove portion in the side wall portion of the case, the reactor of the present disclosure can inject a resin for constituting the sealing resin portion from the bottom plate portion side toward the opening side of the case and prevent the mixing of air bubbles into the sealing resin portion in forming the sealing resin portion. Thus, the reactor of the present disclosure can satisfactorily fill the sealing resin portion between the assembly and the case and satisfactorily release the heat generated in the assembly to the case via the sealing resin portion, and is excellent in heat dissipation. Further, since the sealing resin portion can be satisfactorily filled between the assembly and the case by the groove portion, the interval between the assembly and the case can be reduced and the reactor can be miniaturized.
(2) A second reactor according to an embodiment of the present disclosure is provided with a coil including a pair of winding portions arranged in parallel, a magnetic core to be arranged inside and outside the winding portions, a case for accommodating an assembly including the coil and the magnetic core, and a sealing resin portion to be filled into the case, wherein the case includes a bottom plate portion, the assembly being placed on the bottom plate portion, a side wall portion constituted by a rectangular frame body for surrounding the assembly, and an opening provided on a side opposite to the bottom plate portion, the pair of winding portions are so arranged that axes thereof are orthogonal to the bottom plate portion, the side wall portion includes a pair of short side portions and a pair of long side portions, and the short side portion or the long side portion includes a groove portion continuously provided from the opening side toward the bottom plate portion side and open inward of the case.
In the reactor of the present disclosure, the coil in the case is so arranged that axial directions of both of the pair of winding portions are orthogonal to the bottom plate portion of the case. This arrangement mode is called an upright type. The reactor of the present disclosure including the coil of the upright type can reduce an installation area with respect to the bottom plate portion of the case as compared to a reactor including a coil of the horizontally placed type. This is because a length of the assembly along a direction orthogonal to both a parallel direction of the pair of winding portions and the axial directions of the both winding portions is generally shorter than a length of the assembly along the axial directions of the winding portions. Thus, the reactor of the present disclosure is thin and small in size. Particularly, the reactor of the present disclosure including the coil of the upright type can reduce the installation area with respect to the bottom plate portion of the case as compared to a reactor including a coil of the vertically stacked type if the length of the assembly along the axial directions of the winding portions is longer than a length of the assembly along the parallel direction of the winding portions.
Further, the reactor of the present disclosure including the coil of the upright type is excellent in heat dissipation as compared to the reactor including the coil of the horizontally placed type. This is because the coil of the upright type can increase facing areas of the winding portions and the case and easily releases heat generated in the assembly to the case as compared to the coil of the horizontally placed type.
By providing the groove portion in the side wall portion of the case, the reactor of the present disclosure is small in size and excellent in heat dissipation, similarly to the reactor described in (1) above.
(3) As an example of the reactor of the present disclosure, the groove portion may be provided in the short side portion.
By providing the groove portion in the short side portion of the side wall portion, a thinner reactor is easily obtained.
(4) As an example of the reactor of the present disclosure, the groove portion may be provided in one of the pair of short side portions or one of the pair of long side portions.
By providing the groove portion in one of the pair of short side portions or one of the pair of long side portions, a small-size reactor is easily obtained as compared to the case where the groove portions are provided in both of the pair of short side portions or both of the pair of long side portions. Particularly, by providing the groove portion in one of the pair of short side portions, a thinner reactor is easily obtained.
(5) As an example of the reactor of the present disclosure, at least one of the short side portions including no groove portion and the long side portions including no groove portion has an inner surface inclined inwardly of the case from the opening side toward the bottom plate portion side.
If the interval between the assembly and the case is small, the resin for constituting the sealing resin portion is difficult to flow to the short side portion sides including no groove portion or the long side portion sides including no groove portion in forming the sealing resin portion and it is difficult to satisfactorily form the sealing resin portion between the assembly and the case. Accordingly, by forming the inner surface of at least one of the short side portions including no groove portion and the long side portions including no groove portion by an inclined surface, the resin is easily caused to flow to the short side portion side including no groove portion and the long side portion side including no groove portion and the sealing resin portion is easily formed between the assembly and the case. Particularly, if the short side portion includes the groove portion, the resin is caused to flow to the long side portion sides and a region where the resin is difficult to flow becomes larger. Even in this case, the resin is effectively caused to flow to the long side portion side by forming the inner surface of the long side portion by the inclined surface.
(6) As an example of the reactor of the present disclosure, an edge part of the groove portion on the opening side may be chamfered.
By chamfering the edge part of the groove portion on the opening side of the case, a nozzle for injecting the resin into the groove portion is easily inserted in forming the sealing resin portion. Further, the resin dripped on the edge part of the groove portion can be guided into the case in injecting the resin.
Specific examples of the reactor according to the embodiments of the present disclosure are described below with reference to the drawings. The same components are denoted by the same reference signs in the drawings. Note that the present invention is not limited to these illustrations and is intended to be represented by claims and include all changes in the scope of claims and in the meaning and scope of equivalents.
A reactor 1A of a first embodiment is described with reference to
<<Coil>>
As shown in
The winding wire may be a coated wire including a conductor wire and an insulation coating covering the outer periphery of the conductor wire. A constituent material of the conductor wire may be copper or the like. A constituent material of the insulation coating may be resin such as polyamide-imide. Specific examples of the coated wire include a coated flat rectangular wire having a rectangular cross-sectional shape and a coated round wire having a circular cross-sectional shape. Specific examples of the winding portions 21, 22 formed from a flat rectangular wire include edge-wise coils.
The winding wire of this example is a coated flat rectangular wire. The winding portions 21, 22 of this example are edge-wise coils. In this example, the specifications such as the shapes, winding directions, the numbers of turns and the like of the winding portions 21, 22 are the same. Note that the shapes, sizes and the like of the winding wire and the winding portions 21, 22 can be changed as appropriate. For example, the winding wire may be a coated round wire. Further, the specifications of the respective winding portions 21, 22 may be different.
The winding portions 21, 22 may have a rectangular end surface shape. That is, the winding portion 21, 22 has four corner parts and a pair of long straight portions and a pair of short straight portions connecting the corner parts. The pair of long straight portions are arranged to face each other, and the pair of short straight portions are arranged to face each other. The end surface shape of the winding portion 21, 22 may be a race track shape with four rounded corners. Since the winding portion 21, 22 includes the straight portions, the outer peripheral surface of the winding portion 21, 22 can be substantially formed by flat surfaces. Thus, the flat surfaces of the winding portions 21, 22 and the flat surfaces of the case 5 can face each other. Since the flat surfaces of the winding portions 21, 22 and the flat surfaces of the case 5 can face each other, intervals between the winding portions 21, 22 and the case 5 are easily narrowed.
The coil 2 of this example is of the vertically stacked type. As shown in
<<Magnetic Core>>
As shown in
[Inner Core Portions]
The inner core portions 31, 32 are parts of the magnetic core 3 extending along the axial directions of the winding portions 21, 22. In this example, both end parts of each inner core portion 31, 32 project from the end surfaces of the winding portion 21, 22. These projecting parts are also parts of the inner core portions 31, 32. The end parts of the inner core portions 31, 32 projecting from the winding portions 21, 22 are inserted into through holes (not shown) of the holding members 4 to be described later.
Each inner core portion 31, 32 of this example is in the form of a rectangular parallelepiped substantially corresponding to the inner peripheral shape of the winding portion 21, 22. Further, the inner core portions 31, 32 of this example respectively have the same shape and the same size. Furthermore, each of the inner core portions 31, 32 of this example is an integrated body having an undivided structure.
[Outer Core Portions]
The outer core portions 33 are parts of the magnetic core 3 to be arranged outside the winding portions 21, 22. The outer core portion 33 has an inner end surface facing and in contact with the end surfaces of the inner core portions 31, 32, an outer end surface opposite to the inner end surface, and a peripheral surface connecting the inner and outer end surfaces. The shape of the outer core portion 33 is not particularly limited as long as the outer core portion 33 is shaped to connect the end parts of the two inner core portions 31, 32. Each of the outer core portions 33 of this example is substantially in the form of a rectangular parallelepiped. Further, the outer core portions 33 of this example respectively have the same shape and the same size. Furthermore, each of the outer core portions 33 of this example is an integrated body having an undivided structure.
[Constituent Materials]
The inner core portions 31, 32 and the outer core portions 33 may be formed by compacts including a soft magnetic material. Examples of the soft magnetic material include metals such as iron and iron alloy and non-metals such as ferrite. The iron alloy is, for example, a Fe—Si alloy, a Fe—Ni alloy or the like. The compact may be a powder compact formed by compression-molding a powder made of a soft magnetic material and further a coated powder including an insulation coating. Further, the compact may be a compact of a composite material obtained by solidifying a fluid mixture containing a soft magnetic material and a resin. The soft magnetic powder is dispersed in the resin in the compact of the composite material. Further, the compact containing the soft magnetic material may be a sintered body such as a ferrite core, a laminate formed by laminating plate materials such as electromagnetic steel plates or the like.
The constituent material of the inner core portions 31, 32 and that of the outer core portions 33 may be the same or may be different. An example in which the constituent materials are different is that the inner core portions 31, 32 are compacts of a composite material and the outer core portions 33 are powder compacts. Another example is that both the inner core portions 31, 32 and the outer core portions 33 are compacts of composite materials, but the type and content of a soft magnetic material are different.
<<Holding Members>
The holding members 4 are members for holding the coil 2 and the magnetic core 3 in position. The holding members 4 are typically made of an electrically insulating material and contribute to an improvement in electrical insulation between the coil 2 and the magnetic core 3. The holding members 4 shown in
The holding member 4 includes, for example, a rectangular tube portion for covering the peripheral surface of the outer core portion 33 and an end surface portion arranged on one end surface of the rectangular tube portion to contact the inner end surface of the outer core portion 33. The outer end surface of the outer core portion 33 and a part of the peripheral surface near the outer end surface are exposed from the holding member 4. A part of the inner peripheral surface of the rectangular tube portion is in contact with the peripheral surface of the outer core portion 33, and the outer core portion 33 is held in the rectangular tube portion by this contact part. Other parts of the inner peripheral surface of the rectangular tube portion are not in contact with the peripheral surface of the outer core portion 33, and clearances are formed between these non-contact parts and the peripheral surface of the outer core portion 33. These clearances serve as flow passages for a constituent resin of an unillustrated molded resin portion. The molded resin portion is described in detail in a manufacturing method to be described later. The end surface portion is a B-shaped frame-like member including through holes penetrating from a side where the outer core portion 33 is arranged to a side where the winding portions 21, 22 are arranged. The end parts of the inner core portions 31, 32 are inserted into the through holes. Four corners of the through hole are shaped substantially along the corner parts of the end surface of the inner core portion 31, 32. The inner core portion 31, 32 is held in the through hole by these four corners of the through hole. Edge parts of the through hole connecting the four corners include parts expanded further outward than the contour line of the end surface of the inner core portion 31, 32. With the inner core portions 31, 32 inserted in the through holes, clearances penetrating through the end surface portion are formed in those expanded parts. These clearances serve as flow passages for the constituent resin of the unillustrated molded resin portion. The end surfaces of the inner core portions 31, 32 inserted into the through holes are substantially flush with a surface of the end surface portion on the side where the outer core portion 33 is arranged. Thus, with the inner core portions 31, 32 and the outer core portion 33 held in the holding member 4, the end surfaces of the inner core portions 31, 32 and the inner end surface of the outer core portion 33 are in contact.
The shape, the size and the like of the holding member 4 can be changed as appropriate if the aforementioned function is provided. Further, a known configuration can be utilized for the holding member 4. For example, the holding member 4 may include an inner side portion to be arranged between the winding portions 21, 22 and the inner core portions 31, 32. A peripheral wall portion described in Patent Document 1 may have a shape similar to the inner side portion.
The holding members 4 can be, for example, made of a thermoplastic resin or a thermoplastic resin. The thermoplastic resin is, for example, a polyphenylene sulfide (PPS) resin, a polytetrafluoroethylene (PTFE) resin, a liquid crystal polymer (LCP), a polyamide (PA) resin such as nylon 6 or nylon 66, a polybutylene terephthalate (PBT) resin, an acrylonitrile butadiene styrene (ABS) resin or the like. The thermosetting resin is, for example, an unsaturated polyester resin, an epoxy resin, a urethane resin, a silicone resin or the like. The heat dissipation of the holding members 4 may be improved by containing a ceramic filler in these resins. A non-magnetic powder of alumina, silica or the like can be utilized as the ceramic filler.
<<Case>>
The case 5 has functions of mechanically protecting the assembly 10 and protecting the assembly 10 from an external environment. Protection from an external environment aims to improve corrosion resistance and the like. The case 5 is typically made of a metal material and contributes to an improvement in heat dissipation for releasing heat generated in the assembly 10 to outside. The case 5 is preferably made of metal in terms of heat dissipation, but may be partially or entirely made of resin in terms of weight saving.
The case 5 is a bottomed tubular container including the bottom plate portion 51, the side wall portion 52 and the opening 53. The bottom plate portion 51 is a flat plate member on which the assembly 10 is placed. The side wall portion 52 is a rectangular frame body for surrounding the assembly 10. A space surrounded by the bottom plate portion 51 and the side wall portion 52 serves as an accommodation space for the assembly 10. The opening 53 is formed on a side opposite to the bottom plate portion 51. In this example, the bottom plate portion 51 and the side wall portion 52 are integrally formed.
The side wall portion 52 includes a pair of short side portions 521 and a pair of long side portions 522. The short side portions 521 or the long side portions 522 include the groove portions 520 open inward of the case 5. In this example, both of the pair of short side portions 521 include the groove portions 520. The groove portions 520 are continuously provided from the side of the opening 53 toward the side of the bottom plate portion 51 of the case 5. The groove portions 520 serve as flow passages for resin when a resin for constituting the sealing resin portion 6 is injected from the side of the bottom plate portion 51 toward the side of the opening 53 of the case 5 in forming the sealing resin portion 6 to be described later in the case 5. The resin is injected through the groove portions 520 using nozzles 9 as shown in
Out of the short side portions 521 and the long side portions 522, the side portions including the groove portions 520 are thicker than the side portions including no groove portions 520 (
The size of the groove portion 520 can be selected as appropriate. The size of the groove portion 520 here is a horizontal cross-sectional area of the groove portion 520 cut in a direction orthogonal to a longitudinal direction of the groove portion 520. As the groove portions 520 become larger, the nozzles 9 (
The shape of the groove portion 520 can be selected as appropriate. The shape of the groove portion 520 here is a cross-sectional shape of the groove portion 520 cut in the direction orthogonal to the longitudinal direction of the groove portion 520. The groove portion 520 may be, for example, semicircular, V-shaped or [-shaped. In this example, the groove portion 520 has a semicircular shape.
The formation positions of the groove portions 520 can be selected as appropriate. The groove portions 520 may be provided on both end parts of the short side portion 521 or the long side portion 522. In this example, the groove portions 520 are provided on both end parts of each short side portion 521. The groove portions 520 are provided straight from the side of the opening 53 toward the side of the bottom plate portion 51 of the case 5. If the groove portion 520 is straight, the resistance of the resin flowing in the groove portion 520 can be reduced and the resin is easily injected. Particularly, the groove portion 520 is preferably provided along a direction orthogonal to the bottom plate portion 51. By this arrangement, the groove portion 520 can be made short and the resin is more easily injected. The groove portion 520 may be obliquely provided to intersect the bottom plate portion 51 or may be curved or bent at an intermediate position in the longitudinal direction.
An edge part 520e of the groove portion 520 on the side of the opening 53 of the case 5 is preferably chamfered. By chamfering the edge part 520e, the nozzle 9 (
Out of the side wall portion 52, at least one of the short side portions 521 and the long side portions 522 including no groove portions 520 preferably has an inner surface inclined inwardly of the case 5 from the side of the opening 53 toward the side of the bottom plate portion 51 of the case 5. By forming the inner surface of at least one of the short side portions 521 and the long side portions 522 including no groove portions 520 by an inclined surface, the interval between the assembly 10 and the case 5 becomes larger from the side of the bottom plate portion 51 toward the side of the opening 53. By forming a region where the interval between the assembly 10 and the case 10 is large, the resin is easily caused to flow around the assembly 10 and the satisfactory sealing resin portion 6 is easily formed between the assembly 10 and the case 5. The region where the interval between the assembly 10 and the case 5 is large as compared to the case where the inclined surface is not present is formed by the inclined surface, whereby the assembly 10 is easily arranged in the case 5. In this example, as shown in
The short side portions 521 or the long side portions 522 including the groove portions 520 preferably have inner surfaces along the direction orthogonal to the bottom plate portion 51. The inner surfaces along the direction orthogonal to the bottom plate portion 51 may be simply referred to as orthogonal surfaces below. By forming the inner surfaces of the short side portions 521 or the long side portions 522 including the groove portions 520 by the orthogonal surfaces, the interval between the assembly 10 and the case 5 can be easily narrowed and can be made substantially uniform in a depth direction of the case 5. Since the interval between the assembly 10 and the case 5 can be made narrow and uniform, the assembly 10 can be positioned to a certain extent in the case 5. In this example, inner surfaces 521i of the short side portions 521 are formed by the orthogonal surfaces.
An interval between the assembly 10 and the side wall portion 52 may be 0.5 mm or more and 1 mm or less in a narrowest region. By setting the interval to 0.5 mm or more, the resin is easily filled between the assembly 10 and the side wall portion 52. On the other hand, by setting the interval to 1 mm or less, the small-size reactor 1A is easily obtained. Further, by setting the interval to 1 mm or less, intervals between the winding portions 21, 22 and the side wall portion 52 can be narrowed and the reactor 1A excellent in heat dissipation is easily obtained.
A length of the short side portions 521 may be, for example, 40 mm or more and 80 mm or less. Further, a length of the long side portions 522 may be, for example, 80 mm or more and 120 mm or less. Further, a height of the case 5 may be, for example, 80 mm or more and 150 mm or less. A volume of the reactor 1A may be 250 cm3 or more and 1450 cm3 or less. The length of the short side portions 521 here is an external dimension of the case 5 along a short side direction. Further, the length of the long side portions 522 here is an external dimension of the case 5 along a long side direction. Further, the height of the case 5 here is an external dimension of the case 5 along the depth direction.
The case 5 can be, for example, made of a non-magnetic metal material such as aluminum or aluminum alloy.
<<Sealing Resin Portion>>
The sealing resin portion 6 is filled into the case 5 to at least partially cover the assembly 10. Specifically, the sealing resin portion 6 is disposed in the clearance between the assembly 10 and the case 5. The sealing resin portion 6 is also filled into the groove portions 520. The sealing resin portion 6 has functions of mechanically protecting the assembly 10 and protecting the assembly 10 from an external environment. Protection from an external environment aims to improve corrosion resistance and the like. The sealing resin portion 6 also has a function of improving the strength and rigidity of the reactor 1A by the integration of the assembly 10 and the case 5. The sealing resin portion 6 also has a function of improving electrical insulation between the assembly 10 and the case 5. The sealing resin portion 6 also has a function of improving heat dissipation by transferring the heat of the assembly 10 to the case 5.
The constituent resin of the sealing resin portion 6 is, for example, an epoxy resin, a urethane resin, a silicone resin, an unsaturated polyester resin, a PPS resin or the like. The constituent resin containing a filler excellent in thermal conductivity or a filler excellent in electrical insulation in addition to the above resin component can be utilized for the sealing resin portion 6. The filler is made of a non-metal inorganic material, for example, a non-metal element such as ceramics or carbon nano tubes made of alumina, silica, an oxide such as magnesium oxide, a nitride such as silicon nitride, aluminum nitride or boron nitride or a carbide such as silicon carbide. Besides, known resin compositions can be utilized for the sealing resin portion 6.
<<Manufacturing Method of Reactor>
The aforementioned reactor 1A can be, for example, manufactured via a step of preparing the assembly 10, a step of accommodating the assembly 10 into the case 5 and a step of forming the sealing resin portion 6 in the case 5.
In the step of preparing the assembly 10, the coil 2, the magnetic core 3 and the holding members 4 are assembled to form the assembly 10. At this time, the assembly 10 may be integrated by the unillustrated molded resin portion. Specifically, the outer end surfaces and the peripheral surfaces of the outer core portions 33 are covered by the molded resin portion and the molded resin portion is interposed between the winding portions 21, 22 and the inner core portions 31, 32. With the coil 2 and the magnetic core 3 held in position by the holding members 4, clearances are respectively formed between the rectangular tube portions of the holding members 4 and the outer core portions 33 and between the end surface portions of the holding members 4 and the inner core portions 31, 32. The inner core portions 31, 32 and the outer core portions 33 are integrated by the constituent resin of the resin molded portion injected via these clearances. The winding portions 21, 22 are exposed from the molded resin portion.
The prepared assembly 10 is accommodated into the case 5. At this time, the assembly 10 is so accommodated into the case 5 that the coil 2 is of the vertically stacked type.
The uncured constituent resin of the sealing resin portion 6 is filled into the case 5 having the assembly 10 accommodated therein. The resin is filled in a vacuum tank. The resin is injected via the nozzles 9 inserted between the assembly 10 and the side wall portion 52 along the groove portions 520 as shown in
<<Use Mode>>
The reactor 1A can be utilized as a component of a circuit for performing a voltage stepping-up operation and a voltage stepping-down operation. The reactor 1A can be, for example, used as a constituent component of various converters and power converters. Examples of the converters include in-vehicle converters mounted in vehicles, typically DC-DC converters, and converters of air conditioners. Examples of the vehicle include hybrid vehicles, plug-in hybrid vehicles, electric vehicles and fuel cell vehicles.
<<Effects>>
In the reactor 1A of the first embodiment, the coil 2 is of the vertically stacked type. The reactor 1A including the coil 2 of the vertically stacked type can reduce an installation area with respect to the bottom plate portion 51 of the case 5 as compared to a reactor including a coil of the horizontally placed type. Thus, the reactor 1A of the first embodiment is thin and small in size. Further, the reactor 1A including the coil 2 of the vertically stacked type can increase facing areas of the winding portions 21, 22 and the case 5 as compared to the reactor including the coil of the horizontally placed type. Thus, the reactor 1A of the first embodiment easily releases heat generated in the assembly 10 to the case 5 and can improve heat dissipation.
Further, the reactor 1A of the first embodiment includes the groove portions 520 in the side wall portion 52 of the case 5. Thus, in forming the sealing resin portion 6, the resin for constituting the sealing resin portion 6 can be injected from the side of the bottom plate portion 51 toward the side of the opening 53 of the case 5 and the mixing of air bubbles into the sealing resin portion 6 can be prevented. Thus, the reactor 1A of the first embodiment can satisfactorily fill the sealing resin portion 6 between the assembly 10 and the case 5 and release heat generated in the assembly 10 to the case 5 via the sealing resin portion 6, and is excellent in heat dissipation. Since the sealing resin portion 6 can be satisfactorily filled between the assembly 10 and the case 5 by the groove portions 520, the interval between the assembly 10 and the case 5 can be reduced and the reactor 1A can be miniaturized. Particularly, by providing the groove portions 520 in the short side portions 521 of the side wall portion 52, the reactor 1A can be thinner and smaller in size.
Grooves portions 520 may be provided in one of a pair of short side portions 521 or one of a pair of long side portions 522. For example, in the case of providing the groove portions 520 in the short side portion(s) 521, the groove portions 520 may be provided only in one short side portion 521 as shown in
As shown in
A reactor 1B of a fourth embodiment is described on the basis of
In the coil 2 of the upright type, axes of a pair of winding portions 21, 22 are arranged to be orthogonal to a bottom plate portion 51 as shown in
The case 5 illustrated in
| Number | Date | Country | Kind |
|---|---|---|---|
| 2019-002997 | Jan 2019 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2020/000202 | 1/7/2020 | WO |
| Publishing Document | Publishing Date | Country | Kind |
|---|---|---|---|
| WO2020/145276 | 7/16/2020 | WO | A |
| Number | Name | Date | Kind |
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| 20060201799 | Carrasco-Aguirre | Sep 2006 | A1 |
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| 20160358704 | Suzuki | Dec 2016 | A1 |
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| 20190131052 | Kusawake et al. | May 2019 | A1 |
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| Number | Date | Country |
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| 2009-088007 | Apr 2009 | JP |
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| 2017-028084 | Feb 2017 | JP |
| 2019-212721 | Dec 2019 | JP |
| WO 2015178208 | Nov 2015 | WO |
| Entry |
|---|
| International Search Report issued on Mar. 24, 2020 for WO 2020/145276 A1 (4 pages). |
| Number | Date | Country | |
|---|---|---|---|
| 20220076870 A1 | Mar 2022 | US |
