JP2017163068A - Reactor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reactor where there is no influence by the accumulation of tolerance of multiple members.SOLUTION: A reactor includes a core 10, and a coil 5 wound around a part of the core 10, where the core 10 has an outer leg 10A on the outside of the coil 5 extending in one direction, a middle leg 10B in the coil 5 provided in parallel with the outer leg 10A, and a leg connection 10C for connecting the outer leg 10A and middle leg 10B. The outer leg 10A is constituted by abutting a plurality of core members 11, and the middle leg 10B is constituted of the core members 11, 12, and the gap between the core members 11, 12, where at least one gap is an air gap 14.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a reactor having a core and a coil wound around a part of the core.

  Reactors are used in various applications including drive systems for hybrid vehicles and electric vehicles. For example, a reactor in which a coil is wound around a resin bobbin disposed around a core is often used as a reactor used in an in-vehicle booster circuit.

  The core is composed of a plurality of core members, and in order to avoid magnetic saturation, a gap is provided in the closed magnetic path by arranging spacers between the joint portions of the core members. Conventionally, one gap is provided in the closed magnetic circuit.

JP 2012-253068 A

  As a requirement for the reactor, there is a requirement for securing an inductance at a large current. In order to secure an inductance with a large current in one gap, it is necessary to increase the gap. However, if the gap is thickened, the leakage magnetic flux increases and the loss increases. Therefore, a method of increasing the total thickness of the gaps without increasing the thickness of each gap may be adopted. That is, the total thickness of the gaps may be increased by providing a plurality of gaps.

  However, when a plurality of gaps are provided, the gap is formed between the core members, and therefore, the core needs to be constituted by a plurality of core members. In this case, the following problem may occur. That is, each core member or each spacer has a tolerance variation among individuals. Since the core is composed of such a plurality of members, tolerances increase when a core having a predetermined shape is formed by joining a plurality of core members and spacers. For this reason, the core members may be opened at the locations to be joined, which may adversely affect the magnetic path. For example, a gap is generated at a portion to be joined outside the coil, a leakage magnetic flux is generated from the gap, and the loss increases. For this reason, it is necessary to strictly manage the dimensional tolerance of each member, but there is a problem that it is very difficult to manufacture the individual difference of each member.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a reactor that is not affected by the accumulation of tolerances of a plurality of members.

The reactor of this invention has the following structures, It is characterized by the above-mentioned.
(1) A core and a coil wound around a part of the core are provided.
(2) The core includes an outer leg portion outside the coil extending in one direction, an inner leg portion inside the coil provided in parallel with the outer leg portion, the outer leg portion and the middle leg portion. And a connecting leg portion to be connected.
(3) The outer leg portion is configured by a plurality of core members being abutted against each other.
(4) The middle leg portion includes a core member and a gap between the core members, and at least one of the gaps is an air gap.

The reactor of the present invention may have the following configuration.
(5) The air gap is provided at the center of the middle leg portion.
(6) The core includes a pair of J-shaped cores, an I-shaped core, and a spacer that forms the gap, and the outer legs have long sides of the J-shaped core. The joint leg portion is formed by a folded portion of the J-shaped core, and the middle leg portion includes a short side portion of the J-shaped core, the I-shaped core, and the spacer. And the air gap.

(7) A resin member that covers the periphery of the core is provided, and the resin member has a middle leg covering portion that covers the periphery of the middle leg portion, and the middle leg covering portion is a pair of opposingly arranged The cylindrical body covers the periphery of the core member that forms the air gap, exposes the end surface of the core member that forms the air gap, and the opposite ends of the pair of cylindrical bodies They are spaced apart.
(8) The core is fixed to the inner side of the resin member, and, of the middle leg covering part, the end of one of the opposing cylinders faces the end of the other cylinder. Protrusions were provided.

(9) The resin member includes a fixing portion for fixing the core to an installation target, and the fixing portion is provided not on the outer leg side but on the middle leg side.
(10) The installation target is a case having a heat dissipation property, is accommodated in the case, and is fixed to the case via the fixing portion.
(11) The core forms a closed magnetic circuit, and is fixed to the case so that the closed magnetic circuit is perpendicular to the bottom surface of the case.
(12) The fixing portion is fixed to the case by screw fastening.
(13) The case is filled with a filler, and the air gap is filled with the filler.
(14) The core forms a closed magnetic circuit, and is fixed to the installation target so that the closed magnetic circuit is perpendicular to the installation target.

(15) The outer leg portion is thinner than the middle leg portion.
(16) A pair of core modules including the core and the resin member includes a pressing surface on the back side of the joint leg portion.

  According to the present invention, it is possible to obtain a reactor that is not affected by stacking tolerances of a plurality of members.

It is a perspective view which shows the whole structure of the reactor which concerns on 1st Embodiment. It is a disassembled perspective view which shows the whole structure of the reactor which concerns on 1st Embodiment. It is AA sectional drawing of FIG. It is a figure for demonstrating the manufacturing method of the reactor which concerns on 1st Embodiment, and is a figure which shows a core module. It is a figure for demonstrating the manufacturing method of the reactor which concerns on 1st Embodiment, and is a schematic diagram which shows a mode that a reactor is assembled with a set of core modules. It is a figure which shows the core which concerns on other embodiment. It is a figure which shows the core which concerns on other embodiment. It is a figure for demonstrating the reactor which concerns on other embodiment. It is a figure for demonstrating the relationship between arrangement | positioning of the conventional reactor, and cooling of the said reactor.

  Hereinafter, a reactor according to an embodiment of the present invention will be described with reference to the drawings.

[1. First Embodiment]
[1-1. Schematic configuration]
FIG. 1 is a perspective view showing the overall configuration of the reactor according to the present embodiment, and FIG. 2 is an exploded perspective view thereof. 3 is a cross-sectional view taken along the line AA in FIG. However, the case 4 is not shown in FIG.

  A reactor is an electromagnetic component that converts electric energy into magnetic energy and stores and discharges it, and is used for voltage step-up / step-down and the like. The reactor according to the present embodiment is a large-capacity reactor used in, for example, a drive system for a hybrid vehicle or an electric vehicle. The reactor is a main component of the booster circuit mounted on these automobiles.

  As shown in FIGS. 1 and 2, the reactor covers a core 10 including a magnetic body, a single coil 5 attached to a part of the core 10, and an outer periphery of the core 10. And a resin member 20 that insulates the coil 5 from each other. Here, the reactor is accommodated in the case 4. The case 4 is made of a light metal having high thermal conductivity, such as an aluminum alloy, and has heat dissipation. Although not shown here, a reactor may be accommodated in the case 4, and a filler may be filled in a gap between the case 4 and solidified.

[1-2. Detailed configuration]
The detailed structure of each part of the reactor of this embodiment is demonstrated using FIGS. 1-3. In this specification, the z-axis direction shown in FIG. 1 is the “upper” side, and the opposite direction is the “lower” side. In describing the configuration of each member, “lower” is also referred to as “bottom”. The z-axis direction is the vertical direction of the reactor and the height direction of the reactor.

(core)
As shown in FIGS. 2 and 3, the core 10 has a flat and generally annular shape as a whole. Specifically, the core 10 includes an outer leg portion 10A outside the coil 5 extending in one direction, an inner leg portion 10B inside the coil 5 provided in parallel with the outer leg portion 10A, an outer leg portion 10A, and an inner leg portion. It has a pair of joint legs 10C that are orthogonal to the legs 10B and connect the outer legs 10A and the middle legs 10B to form an annular shape.

  Of the core 10, the middle leg portion 10 </ b> B is a portion where magnetic flux is generated because the coil 5 is wound around. The joint leg portion 10C and the outer leg portion 10A are yoke portions through which the magnetic flux generated in the middle leg portion 10B passes without the coil 5 being wound. An annular closed magnetic circuit is formed in the core 10 by allowing the magnetic flux generated in the middle leg portion 10B to pass through the joint leg portion 10C and the outer leg portion 10A serving as the yoke portion. The core 10 is disposed such that the closed magnetic path is perpendicular (vertical) to the bottom surface of the case 4. That is, the shaft passing through the annular hole of the core 10 is arranged so as to be parallel to the bottom surface of the case 4. The outer leg portion 10A is thinner than the middle leg portion 10B. That is, the dimension of the outer leg portion 10A in the z-axis direction is smaller than the dimension of the middle leg portion 10B in the z-axis direction.

  The core 10 includes a magnetic body. 2 and 3, the core 10 includes a plurality of core members 11 and 12 and a plurality of spacers 13, and the spacers 13 are arranged between the core members 11 and 12 by an adhesive. They are connected so as to form a generally annular shape.

  The core members 11 and 12 are made of a magnetic material such as a dust core, a ferrite core, or a laminated steel plate. Here, the core members 11 and 12 are dust cores. The core member 11 is a J-shaped core 11 and includes a long side portion, a folded portion, and a short side portion as is apparent from its shape. The core member 12 is an I-shaped core 12. The I-shaped core 12 has a substantially rectangular parallelepiped shape.

  As shown in FIG. 3, the outer leg portion 10 </ b> A is configured by a pair of J-shaped cores 11 being butted together. In other words, the long sides of the J-shaped core 11 are configured to face each other. You may join the said long side part by interposing an adhesive agent between the end surfaces faced together. The joint leg portion 10 </ b> C is configured by a folded portion of the J-shaped core 11.

  The middle leg portion 10 </ b> B includes a plurality of core members 11, 12 and a gap, and at least one of the gaps is an air gap 14. In the present embodiment, the middle leg portion 10 </ b> B includes a short side portion of the J-shaped core 11, two I-shaped cores 12, two spacers 13, and an air gap 14. That is, the middle leg portion 10B includes a set of blocks each including the short side portion of the J-shaped core 11, the spacer 13, and the I-shaped core 12 as one block. The length in the extending direction of the outer leg portion 10A of the block is shorter than the length of the long side portion of the J-shaped core 11 constituting the half of the outer leg portion 10A. In the middle leg portion 10B, the length in the extending direction of the outer leg portion 10A excluding the air gap 14 is shorter than that of the outer leg portion 10A.

  The spacer 13 is a plate-shaped gap spacer and forms a gap between the core members. Here, the spacer 13 is disposed in a gap formed between the short side portion of the J-shaped core 11 and the I-shaped core 12, and the core members 11, 12 on both sides of the spacer 13 are bonded by an adhesive. Bonded to the connection surface. The spacer 13 provides a magnetic gap having a predetermined width between the core members 11 and 12 to prevent a reduction in the inductance of the reactor. As a material of the spacer 13, a non-magnetic material, ceramic, non-metal, resin, carbon fiber, or a synthetic material of two or more of these or gap paper can be used.

  The air gap 14 is a variable gap in which the end surfaces of the core member are spaced apart and the distance between the end surfaces can change. Here, the air gap 14 is a gap between the end faces of the I-shaped core 12. In the present embodiment, the air gap 14 is provided at the center of the middle leg portion 10B. Although the air gap 14 may be left as an air gap, the air gap 14 functions to absorb the accumulation of dimensional tolerances of a plurality of members during the assembly of the reactor. Therefore, after the reactor is assembled, the reactor May be accommodated in the case 4 and the case 4 may be filled with a filler so that the air gap 14 is filled with the filler and solidified.

  In the present embodiment, the middle leg portion 10B has two I-shaped cores 12 and two spacers 13, but may be one or three or more. The arrangement of the air gap 14 is not limited to the center of the middle leg portion 10B.

(Resin member)
The resin member 20 is a member that covers the outer periphery of the core 10 with resin. Therefore, the resin member 20 is formed in a substantially annular shape following the shape of the core 10.

  Examples of the resin constituting the resin member 20 include an epoxy resin, an unsaturated polyester resin, a urethane resin, BMC (Bulk Molding Compound), PPS (Polyphenylene Sulfide), and PBT (Polybutylene Terephthalate).

  As shown in FIG. 2, in the present embodiment, the resin member 20 is divided into two parts, and includes a substantially U-shaped resin body 21 and a resin body 22, respectively. That is, the resin member 20 is configured by separately molding a substantially U-shaped resin body 21 and a substantially U-shaped resin body 22 and facing one end of each other. The resin body 21 and the resin body 22 are molded separately in order to accommodate the I-shaped core 12 and the spacer 13 that constitute the middle leg portion 10B inside, and the coil 5 is made U of the resin bodies 21 and 22. This is because the coil 5 is attached to the resin member 20 by fitting into the leg portion of the character.

  The resin body 21 includes cylindrical bodies 21a and 21b, a connecting portion 21c that connects these cylindrical bodies 21a and 21b, and a fixing portion 31. The resin body 22 includes cylindrical bodies 22a and 22b, a connecting portion 22c that connects these cylindrical bodies 22a and 22b, and a fixing portion 31.

  In the present embodiment, the resin bodies 21 and 22 are members integrally formed of resin. That is, the cylinders 21a and 21b, the connecting portion 21c, and the fixing portion 31 that constitute the resin body 21 are configured in a continuous manner without a joint. Similarly, the cylindrical bodies 22a and 22b, the connecting portion 22c, and the fixing portion 31 that constitute the resin body 22 are also seamlessly configured.

  The cylindrical bodies 21a and 22a are outer leg covering portions that cover the periphery of the outer leg portion 10A, and the long side portion of the J-shaped core 11 is embedded therein by a molding method. The peripheral surface of the J-shaped core 11 is in close contact with and fixed to the inner peripheral surfaces of the cylinders 21a and 22a. The cylinders 21a and 22a have flat ends, are provided on the same plane as the end face of the long side portion of the J-shaped core 11, and the ends of the cylinders 21a and 22a facing each other are abutted. The said edge part may be adhere | attached through the adhesive agent.

  The cylindrical bodies 21b and 22b are middle leg covering portions that cover the periphery of the middle leg portion 10b, and are portions to which the coil 5 is attached. The cylinders 21 b and 22 b cover the periphery of the I-shaped core 12 that forms the air gap 14 and expose the end surface of the I-shaped core 12 that forms the air gap 14. The opposite ends of the cylinders 21b and 22b are flat surfaces. The opposing ends of the cylinders 21b and 22b are spaced apart. The I-shaped core 12 and the spacer 13 may be arranged by inserting the spacer 13 and the I-shaped core 12 through the openings of the cylinders 21b and 22b. Alternatively, the J-shaped core 11 and the adhesive may be placed in advance. The spacer 13 and the I-shaped core 12 may be bonded together to form a substantially U-shaped core, and the U-shaped core may be disposed so as to be covered with a resin by a molding method.

  The connection parts 21c and 22c are joint covering parts that cover the periphery of the joint part 10C. The connecting portions 21c and 22c are provided with an opening through which the back surface of the joint leg portion 10C, that is, the outer surface of the folded portion of the J-shaped core 11 is exposed.

  The fixing part 31 is a part for fixing the reactor or the core 10 to the case 4 to be installed. The fixing portion 31 is provided with a screw insertion hole, and a metal cylindrical collar (not shown) is embedded in the hole. The reactor 32 is fixed to the case 4 by inserting the screw 32 into the screw insertion hole and fastening the screw.

  The fixing portion 31 is provided not on the outer leg portion 10A side but on the middle leg portion 10B side. That is, it is provided below the resin member 20. Here, the two fixing portions 31 are provided on the diagonal line of the reactor and beside the connecting portions 21c and 22c. The number of the fixing parts 31 is not particularly limited. For example, four may be provided at the lower four corners of the resin member 20.

(coil)
The coil 5 is a conducting wire having an insulating coating. In this embodiment, the coil 5 is a flat wire edgewise coil, and is composed of one copper wire covered with an insulating material such as enamel. However, the wire material and winding method of the coil 5 are not limited to the rectangular wire edgewise coil, and may be in other forms.

  The coil 5 is attached to the outer periphery of the middle leg covering portion so as to surround the periphery of the middle leg portion 10B in the air core portion. Both ends of the coil 5 are drawn out of the reactor and are electrically connected to wiring of an external device such as an external power source. When electric power is supplied from an external power source, a current flows through the coil 5 to generate a magnetic flux penetrating the coil 5, and a closed magnetic circuit is formed in the core 10.

(Case)
The case 4 is a housing member that houses the reactor main body 1. The case 4 is made of a light metal having high thermal conductivity, such as an aluminum alloy, and has heat dissipation.

  In the present embodiment, the case 4 has a substantially rectangular parallelepiped shape with an opening on the upper surface, and is mainly composed of a bottom surface and a side wall rising from the edge of the bottom surface. Have a space.

  The accommodation space of the case 4 is slightly larger than the size of the reactor. Therefore, when the reactor main body 1 is accommodated in the case 4, a gap is formed between the inner surface of the side wall of the case 4 and the side surface of the reactor.

  In the gap between the reactor and the case 4, a filling molding part (not shown) in which a filler is filled and solidified may be provided. The shape of the filling molding part is such that the upper surface part follows the shape of the reactor, and the lower surface part follows the shape of the bottom surface of the case 4. As the filler, a resin that is relatively soft and has high thermal conductivity is suitable for ensuring the heat dissipation performance of the reactor and reducing the vibration propagation from the reactor to the case 4. Moreover, it is preferable that a filler has insulation.

  As a forming method of the filling molding part, after the reactor is accommodated in the case 4, the filler may be filled and solidified, or the case 4 is previously filled with the filler, and then the reactor main body 1 is accommodated. The filler may be solidified.

  Note that a screw hole into which a screw 32 inserted into the fixing portion 31 is inserted is provided on the bottom surface forming the accommodation space of the case 4. The side wall of the case 4 is provided with a screw hole that is fixed to the base that is the installation target of the reactor accommodated in the case 4 by screw fastening or the like.

[1-3. Reactor manufacturing method]
The manufacturing method of the reactor of this embodiment is demonstrated using FIG.4 and FIG.5. In addition, the manufacturing method shown below is an example and is not limited to this.

(1) Fabrication of a pair of core modules 1 and 2 First, as shown in FIG. 4, the core module 1 including the J-shaped core 11, the I-shaped core 12, the spacer 13, and the resin body 21, and the J-shaped The core module 2 including the core 11, the I-shaped core 12, the spacer 13, and the resin body 22 is manufactured. Since the core modules 1 and 2 are substantially U-shaped and have the same shape, the production of the core module 1 will be described below.

  Specifically, the resin body in which the J-shaped core 11 is embedded by setting the J-shaped core 11 as an insert product in a predetermined mold, filling the mold with resin, and solidifying the resin. 21 is produced. At this time, the end face of the long side portion of the J-shaped core 11 is exposed from the opening of the cylinder 21a, and the end face and the end of the cylinder 21a are flush with each other. Next, the spacer 13 and the I-shaped core 12 are inserted into the cylindrical body 21b from the opening of the cylindrical body 21b and fixed with an adhesive. That is, the J-shaped core 11, the spacer 13, and the I-shaped core 12 are integrated. At this time, the end face of the I-shaped core 12 is exposed from the opening of the cylinder 21b and slightly protrudes from the end of the cylinder 21b. Moreover, the length of the short side part of the J-shaped core 11 which comprises the middle leg part 10B, the spacer 13, and the I-shaped core 12 is shorter than the length which comprises the outer leg part 10A.

  The molded body may be molded after the J-shaped core 11, the spacer 13, and the I-shaped core 12 are integrated.

(2) Attaching the coil 5 and butting the core modules 1 and 2 After producing the pair of core modules 1 and 2, an adhesive is applied to the end face of the J-shaped core 11 and the end of the cylindrical body 21a, and the coil 5 Is fitted into the cylinders 21b and 22b of the core modules 1 and 2. Then, as shown in FIG. 5, the outer legs 10 </ b> A are configured by pressing each module 1, 2 in the direction in which the modules 1 and 2 are brought closer to each other and abutting and joining the end faces of the J-shaped core 11. This pressing presses the pressing surface S provided on the back side of the joint leg portion 10 </ b> C of the core modules 1 and 2. The pressing surface S is a plane orthogonal to the extending direction of the outer leg portion 10A, and is particularly a region intersecting with the extending direction of the outer leg portion 10A. Here, the pressing surface S is configured by the outer surfaces of the connecting portions 21c and 22c and the joint leg portion 10C.

  In a state where the end surfaces of the J-shaped core 11 are pressed in this way, the length of each member constituting the middle leg portion 10B is shorter than the outer leg portion 10A, so that the I-shaped cores 12 are joined together. First, the end surfaces of the I-shaped core 12 are separated from each other. That is, the air gap 14 is formed.

  Thus, a reactor is produced and accommodated in the case 4 as needed.

[1-4. Action / Effect]
(1) The reactor of the present embodiment includes a core 10 and a coil 5 wound around a part of the core 10, and the core 10 includes an outer leg 10A outside the coil 5 extending in one direction, and an outer The coil 5 includes a middle leg 10B provided in parallel with the leg 10A, and an outer leg 10A and a joint leg 10C that connects the middle leg 10B. The outer leg 10A includes a plurality of core members. 11, the middle leg portion 10B is composed of core members 11 and 12 and a gap between the core members 11 and 12, and at least one of the gaps is an air gap 14.

  Thereby, even when the core 10 is constituted by a plurality of members, the stack of tolerances of the plurality of members can be absorbed by the air gap 14, so that a gap is not generated in the outer leg portion 10 </ b> A located outside the coil 5. A reactor that is not affected by the accumulation of tolerances can be obtained.

  Specifically, the core 10 includes a pair of J-shaped cores 11, an I-shaped core 12, and a spacer 13 that forms a gap, and the outer leg portion 10 </ b> A is a length of the J-shaped core 11. The side portions are configured to face each other, the joint leg portion 10 </ b> C is configured by a folded portion of the J-shaped core 11, and the middle leg portion 10 </ b> B includes the short side portion of the J-shaped core 11 and the I-shaped core 12. And a spacer 13 and an air gap 14.

  Thereby, the downsized reactor can be obtained. According to the present invention, as shown in FIG. 6 to be described later, the core 10 is constituted by a pair of E-shaped core 15, I-shaped core 12, spacer 13, and air gap 14, and the central middle leg portion 10B Although it is possible to mount the coil 5, the coil 5 is surrounded by the core 10 at the entire circumference of the coil 5, that is, at the inner and outer circumferences and at both ends. 5 clearances need to be provided. On the other hand, according to this embodiment, since there is only one outer leg portion 10A, the number of places where clearance is provided can be reduced, and the size can be reduced.

(2) The air gap 14 is provided at the center of the middle leg portion 10B. Thereby, since the shape of magnetic flux becomes symmetrical, a magnetic characteristic without a bias can be obtained.

(3) A resin member 20 that covers the periphery of the core 10 is provided, and the resin member 20 has a middle leg covering portion that covers the periphery of the middle leg portion 10B, and the middle leg covering portion is a pair of opposingly arranged. The cylinders 21b and 22b are formed of a pair of cylinders 21b and 22b that cover the periphery of the core members 11 and 12 that form the air gap 14, and that the end surfaces of the core member 12 that form the air gap 14 are exposed. The opposite ends of the cylindrical bodies 21b and 22b are provided apart from each other.

  Thereby, a filler and an adhesive agent can be interposed between the end surfaces of the core member 12 that forms the air gap 14 between the ends of the cylinders 21b and 22b. In other words, the air gap 14 is used to absorb the stack of tolerances of a plurality of members when assembling the reactor, and thereafter, if necessary, the gap between the core members 12 is filled to prevent generation of noise due to magnetic attractive force. can do.

(4) The resin member 20 includes a fixing portion 31 for fixing the core 10 to the installation target, and the fixing portion 31 is provided not on the outer leg portion 10A side but on the middle leg portion 10B side. Thereby, even if a magnetic attractive force acts on the core members 11 and 12 of the middle leg portion 10B, the influence of the magnetic attractive force can be suppressed by fixing the fixing portion 31 to the installation target.

(5) The case 4 to be installed is the case 4 having heat dissipation, and is accommodated in the case 4 and fixed to the case 4 via the fixing portion 31. Thereby, the heat of a reactor can be escaped to case 4, and heat dissipation can be improved.

(6) The core 10 forms a closed magnetic circuit, and the reactor is fixed to the case 4 so that the closed magnetic circuit is perpendicular to the bottom surface of the case 4. Thereby, even if the width direction of the core 10 is lengthened, the magnetic path length of the core 10 is not increased and the inductance is not lowered, and the heat dissipation can be further improved.

  That is, as shown in FIG. 9, a conventional reactor formed by abutting a pair of U-shaped cores to form an annular core 110 is cooled so that two coils 105 wound around the annular core 110 are in contact with each other. If the length in the width direction (x direction) of the core is increased, the contact area with the cooling surface CS is increased and the heat dissipation can be improved. However, since the magnetic path length and the inductance are in an inversely proportional relationship, the magnetic path length in the annular core 110 is increased, and the obtained inductance is reduced. On the other hand, according to the present embodiment, the core 10 is arranged so that the closed magnetic path is perpendicular to the case 4 that also serves as a cooling member. Therefore, even if the length of the core 10 in the width direction is increased. In addition, since the contact area with the bottom surface of the case 4 can be increased without changing the magnetic path length, that is, without reducing the inductance, only the merit that the heat dissipation can be further improved can be enjoyed.

(7) The fixing portion 31 is fixed to the case 4 by screw fastening. When fixing by screw fastening in this manner, the entire reactor may be deformed due to the fastening force, but since it is fixed with the air gap 14 provided, there is a free end in the middle leg portion 10B. Therefore, the stress applied to the entire reactor by the fastening force can be relaxed, and a reactor excellent in durability can be obtained.

(8) The case 4 is filled with a filler, and the air gap 14 is filled with a filler. Thereby, even if a magnetic attractive force acts on the core members 11 and 12 of the middle leg portion 10B, it is possible to eliminate a room for the core members 11 and 12 to move due to the magnetic attractive force by the filler. Therefore, since the core members 12 do not collide with each other, generation of noise can be suppressed.

(9) The outer leg portion 10A is thinner than the middle leg portion 10B. Thereby, a reactor can be reduced in size. In addition, since the magnetic flux which passes through the inside of the core 10 tends to pass through the inside of the core 10, it hardly affects the magnetic characteristics of the reactor.

(10) The pair of core modules 1 and 2 having the core 10 and the resin member 20 are provided with the pressing surface S on the back side of the joint leg portion 10C. Accordingly, the long side portions of the J-shaped core 11 constituting the outer leg portion 10A can be reliably butted so that no gap is generated in the outer leg portion 10A.

[2. Other Embodiments]
The present invention is not limited to the first embodiment, and includes other embodiments described below. Moreover, the present invention also includes a form in which the first embodiment and the following other embodiments are all or any combination thereof. Furthermore, various omissions, replacements, and modifications can be made to these embodiments without departing from the scope of the invention, and modifications thereof are also included in the present invention.

(1) In the first embodiment, the core 10 is used as the core member, and the J-shaped core 11 and the I-shaped core 12 are used. However, the shape of the core member is not limited thereto. As long as an annular shape can be formed, an E-shaped core, a C-shaped core, a T-shaped core, a cylindrical core, or the like may be used. For example, as shown in FIG. 6, a pair of E-shaped cores 15 may be configured to face each other. Specifically, the E-shaped core 15 includes a pair of outer legs 15a, an intermediate leg 15b between the outer legs 15a, an outer leg 15a, and a joint leg 15c that connects the intermediate legs 15b. The outer legs 15 a of the E-shaped core 15 are butted together, and the I-shaped core 12 is connected to the middle leg 15 b of one E-shaped core 15 via the spacer 13. The air gap 14 may be formed without joining the leg 15b. The middle leg 15b of the E-shaped core 15 constitutes the middle leg 10B. The outer leg of the E-shaped core constitutes the outer leg portion 10A. Thus, the core 10 may have a plurality of outer leg portions 10A with respect to the middle leg portion 10B around which the coil 5 is wound.

  As shown in FIG. 7, the core 10 may be composed of a pair of C-shaped core 16, I-shaped core 17, I-shaped core 12, spacer 13, and air gap 14. One end portion of the two C-shaped cores 16 and the I-shaped core 17 are abutted to constitute an outer leg portion 10A, and one end portion of the two C-shaped cores 16, the I-shaped core 12, the spacer 13, and The middle leg portion 10 </ b> B is formed from the air gap 14. A portion connecting both ends of the C-shaped core 16 constitutes a joint leg portion 10C. The C-shaped core 16 and the I-shaped core 17 differ from the other J-shaped core 11 and the I-shaped core 12 only in shape, and the constituent materials are the same.

  As another example of the core 10 having a plurality of outer leg portions 10A, three outer leg portions 10A are arranged at the positions of the vertices of an equilateral triangle, and the middle leg portions 10b are arranged at the center position of the equilateral triangle. You may do it. The joint leg portion 10C connects the outer leg portion 10A and the middle leg portion 10B so as to connect the center of the equilateral triangle and each vertex.

(2) In the first embodiment, one air gap 14 is provided in the core 10, but two or more may be provided. For example, not only the air gap 14 at the center of the middle leg portion 10B but also the sizes of the cylinders 21b and 22b are made substantially the same so that the inner circumference and the outer circumference of the I-shaped core 12 are in contact with each other. An air gap 14 may be formed between the short side portion of the J-shaped core 11 and the I-shaped core 12 by press-fitting the I-shaped core 12. However, the present invention is not limited to this, and two or more air gaps 14 may be provided by other methods.

(3) In the first embodiment, the coil 5 has been described as an example, but a plurality of coils 5 may be provided.

(4) In the first embodiment, the end portions of the cylinders 21b and 22b and the end surface of the I-shaped core 12 are flush with each other, but as shown in FIG. 8, either the cylinder body 21b or the cylinder body 22b is used. You may provide the protrusion 23 which faced the edge part of the other cylinder 21b or the cylinder 22b in the edge part. Thereby, generation | occurrence | production of noise can be prevented. That is, since the I-shaped core 12 constituting the air gap 14 of the middle leg portion 10B is integrated with the inner periphery of the resin member 20 and the fixed J-shaped core 11, a magnetic flux is generated inside the coil 5. Then, it becomes N pole and S pole and tries to be displaced by the magnetic attractive force. Therefore, there is a possibility that the air gap 14 contracts and the I-shaped cores 12 collide with each other. However, by providing the projection 23 at the end of the cylindrical body 21b or the cylindrical body 22b, the projection 23 becomes the other cylindrical body 21b or Since it will contact | abut with the edge part of the cylinder 22b, the protrusion 23 becomes a support and the collision of I-shaped cores 12 can be prevented. As a result, generation of noise can be suppressed.

(5) In the first embodiment, the ends of the cylinders 21a and 22a are provided with a claw extending toward the other cylinder 21a and 22a and a claw hole into which the claw is fitted, and aligned. May be.

(6) In the first embodiment, as an aspect of use of the present reactor, the present reactor is accommodated in the case 4 and filled with the filler, thereby filling the air gap 14 with the filler and solidifying it. However, it may be used as follows. That is, after assembling the reactor, a spacer 13 having a thickness matching the end face spacing of the I-shaped core 12 forming the air gap 14 may be inserted into the air gap 14 and interposed, or an adhesive may be interposed. You may do it.

(7) In 1st Embodiment, although the installation object of the reactor was made into the case, it is not limited to this. It may be a metal heat radiating member such as a cooling plate, a PCU case, a voltage control unit case, a mission case, or a heat sink. The reactor may be fixed to the installation target such that the closed magnetic path formed by the core is perpendicular to the installation target.

1, 2 Core module 10 Core 10A Outer leg 10B Middle leg 10C Joint leg 11 J-shaped core 12 I-shaped core 13 Spacer 14 Air gap 15 E-shaped core 15a Outer leg 15b Middle leg 15c Joint leg 16C Character-shaped core 17 I-shaped core 20 Resin member 21 Resin bodies 21a, 21b Tubular body 21c Connecting part 22 Resin bodies 22a, 22b Tubing body 22c Connecting part 23 Projection 31 Fixing part 32 Screw 4 Case 5 Coil S Press surface

Claims (13)

The core,
A coil wound around a part of the core;
With
The core includes an outer leg portion outside the coil extending in one direction, a middle leg portion inside the coil provided in parallel with the outer leg portion, and a joint leg connecting the outer leg portion and the middle leg portion. And
The outer leg portion is configured by a plurality of core members being abutted,
The middle leg portion is composed of a core member and a gap between the core members, and at least one of the gaps is an air gap.
Reactor characterized by. The air gap is provided in the center of the middle leg,
The reactor according to claim 1. The core includes a pair of J-shaped cores, an I-shaped core, and a spacer that forms the gap,
The outer leg portion is configured by abutting long side portions of the J-shaped core,
The joint leg portion is constituted by a folded portion of the J-shaped core,
The middle leg portion is composed of a short side portion of the J-shaped core, the I-shaped core, the spacer, and the air gap.
The reactor according to claim 1 or 2, characterized in that. A resin member covering the periphery of the core;
The resin member has a middle leg covering portion that covers the periphery of the middle leg portion,
The middle leg covering portion is composed of a pair of cylinders arranged to face each other,
The cylindrical body covers the periphery of the core member that forms the air gap, exposes an end surface of the core member that forms the air gap, and the opposed end portions of the pair of cylindrical bodies are separated from each other. Is provided,
The reactor of any one of Claims 1-3 characterized by these. The core is fixed to the inside of the resin member,
Of the middle leg covering part, a protrusion facing the end of the other cylindrical body is provided at one end of the opposing cylindrical body,
The reactor according to claim 4. The resin member includes a fixing portion for fixing the core to an installation target,
The fixing portion is provided not on the outer leg side but on the middle leg side;
The reactor of Claim 4 or Claim 5 characterized by these. The installation target is a case having heat dissipation,
Being accommodated in the case and being fixed to the case via the fixing portion;
The reactor according to claim 6. The core forms a closed magnetic circuit;
Being fixed to the case so that the closed magnetic path is perpendicular to the bottom surface of the case;
The reactor according to claim 7. The fixing portion is fixed to the case by screw fastening;
The reactor of any one of Claims 6-8 characterized by these. The case is filled with a filler,
The air gap is filled with the filler,
The reactor of any one of Claims 7-9 characterized by these. The core forms a closed magnetic circuit;
Being fixed to the installation target such that the closed magnetic path is perpendicular to the installation target;
The reactor according to claim 6. The outer leg is thinner than the middle leg;
The reactor of any one of Claims 1-11 characterized by these. A pair of core modules having the core and the resin member, each having a pressing surface on the back side of the joint leg;
The reactor of any one of Claims 4-12 characterized by these.

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