阅读说明：本技术 电抗器的制造方法及电抗器 (Method for manufacturing reactor and reactor ) 是由 船桥和树 上野泰弘 内田裕希 高桥直是 村田木绵子 近藤贵文 于 2021-03-08 设计创作，主要内容包括：电抗器的制造方法具有：线圈塑模工序,在该工序中,以覆盖线圈(10)的至少一部分的方式,形成由第一树脂被塑模而得到的线圈塑模；以及主体塑模工序,在该工序中,以覆盖组装体的至少一部分的方式形成由第二树脂被塑模而得到的主体塑模,组装体是将线圈、线圈塑模、两个I芯、包围线圈及线圈塑模的O芯组装而得到的,在线圈塑模工序中,利用第一树脂将对两个I芯所配置的位置之间的间隙进行填埋的间隙板进行塑模成型,在主体塑模工序中,利用第二树脂将对各I芯与O芯之间的间隙进行填埋的间隙板进行塑模成型。(A method for manufacturing a reactor includes: a coil molding step of forming a coil mold molded from a first resin so as to cover at least a part of the coil (10); and a main body molding step of forming a main body mold obtained by molding a second resin so as to cover at least a part of the assembly, the assembly being obtained by assembling the coil, the coil mold, the two I cores, and the O core surrounding the coil and the coil mold, wherein in the coil molding step, the gap plate filling the gap between the positions where the two I cores are arranged is molded by the first resin, and in the main body molding step, the gap plate filling the gap between each of the I cores and the O core is molded by the second resin.)

1. A method of manufacturing a reactor having a coil, two I-shaped cores, and an O-shaped core capable of surrounding the two I-shaped cores,

the method for manufacturing the reactor at least comprises the following steps:

a coil molding step of forming a coil mold in which a first resin is molded so as to cover at least a part of the coil; and

a body molding step of forming a body mold obtained by molding a second resin so as to cover at least a part of an assembly obtained by assembling the coil, the coil mold, the two I cores arranged in parallel in the coil, and the O core surrounding the coil and the coil mold,

in the coil molding step, a first gap plate that fills a gap between positions where the two I cores are arranged is molded with the first resin,

in the body molding step, a second gap plate is molded with the second resin, and the second gap plate fills gaps between the I cores and the O cores.

2. The reactor manufacturing method according to claim 1, wherein,

in the body molding step, a pin is provided between each of the I cores and the O core, and each of the I cores is pressed against the first gap plate by the pin.

3. The reactor manufacturing method according to claim 1 or 2, wherein,

the gap between the two I cores is the thickness of the first gap plate in the direction in which the two I cores are parallel, and the gap between each I core and the O core is the thickness of the second gap plate in the direction in which the two I cores are parallel.

4. The reactor manufacturing method according to any one of claims 1 to 3, wherein,

in the body molding step, the second resin is injected into each of the I cores from both outer sides in the direction in which the two I cores are arranged, so as to press each of the I cores against the first gap plate.

5. A kind of reactor is disclosed, which comprises a reactor body,

comprising: a coil;

a coil mold molded from a first resin so as to cover at least a part of the coil;

two I-shaped cores which are arranged in the coil in parallel;

an O-shaped core surrounding the coil and the coil mold; and

a main body mold obtained by molding a second resin so as to cover at least a part of an assembly obtained by assembling the coil, the coil mold, the two I cores, and the O core,

the coil mold includes a first gap plate molded with the first resin mold, the first gap plate burying a gap between the two I cores,

the body mold includes a second gap plate molded with the second resin mold, the second gap plate burying a gap between each I-core and the O-core.

6. The reactor according to claim 5, wherein,

the first gap plate is integrally formed with the coil mold,

the second gap plate is integrally formed with the body mold.

7. The reactor according to claim 5 or 6, wherein,

the gap between the two I cores is the thickness of the first gap plate in the direction in which the two I cores are arranged,

the gap between each I core and the O core is the thickness of the second gap plate in the direction in which the two I cores are juxtaposed.

8. The reactor according to any one of claims 5 to 7, wherein,

the first resin and the second resin contain the same material.

9. The reactor according to any one of claims 5 to 8,

each of the I cores is surrounded by the coil mold and the body mold.

Technical Field

The present invention relates to a reactor and a method for manufacturing the same.

Background

Japanese patent laid-open No. 2012-119545 describes the following: the inner bottom surface of the case when the resin is molded is formed as a plurality of surfaces having two or more different surface heights with respect to the bottom surface outside the case as a reference surface, and the lower end surface of the core housed in the case is brought into contact with any one surface other than the surface having the lowest surface height in the bottom surface inside the case, whereby the flowability of the molded resin in the case is improved.

Jp 2018 a-082129 a describes a reactor having two I-shaped cores and an O-shaped core.

Disclosure of Invention

In the case of a reactor including two I-shaped cores and one O-shaped core, it is necessary to assemble the gap distance between the I-shaped cores and the O-shaped cores with high accuracy. Therefore, a shape such as japanese patent application laid-open No. 2012 and 119545 is considered, but when the shape such as japanese patent application laid-open No. 2012 and 119545 is formed, the shape becomes complicated, and therefore, a problem arises that the cost at the time of manufacturing increases.

The present invention has been made to solve the above problems, and provides a method for manufacturing a reactor and a reactor, which can reduce manufacturing costs.

A method of manufacturing a reactor according to the present embodiment is a method of manufacturing a reactor including a coil, two I cores in an I shape, and an O core in an O shape capable of surrounding the two I cores, the method including at least: a coil molding step of forming a coil mold in which a first resin is molded so as to cover at least a part of the coil; and a body molding step of molding a body mold in which an assembly is formed by assembling the coil, the coil mold, the two I cores arranged in parallel in the coil, and the O core surrounding the coil and the coil mold, so as to cover at least a part of the assembly, wherein in the coil molding step, a first gap plate is molded with the first resin, the first gap plate filling a gap between positions where the two I cores are arranged, and in the body molding step, a second gap plate is molded with the second resin, the second gap plate filling a gap between each of the I cores and the O core. According to this configuration, since the first gap plate that fills the gap between the positions where the two I cores are arranged is molded by the first resin in the coil molding step, the manufacturing cost can be reduced.

In the above-described method of manufacturing a reactor, in the body molding step, a pin may be provided between each of the I cores and the O core, and each of the I cores may be pressed against the first gap plate by the pin. With this configuration, the accuracy of the gap between the I cores can be improved, and the magnetic field characteristics can be improved.

In the above-described method for manufacturing a reactor, the gap between the two I cores may be a thickness of the first gap plate in the two I core parallel directions, and the gap between each I core and the O core may be a thickness of the second gap plate in the two I core parallel directions. With this configuration, the accuracy of the gap between the I cores can be improved, and the magnetic field characteristics can be improved.

In the above-described method of manufacturing a reactor, in the body molding step, the second resin may be injected into each of the I cores from both outer sides in a direction in which the two I cores are arranged, so as to press each of the I cores against the first gap plate. With this configuration, the accuracy of the gap between the I cores can be improved, and the magnetic field characteristics can be improved.

The reactor according to the present embodiment includes: a coil; a coil mold molded from a first resin so as to cover at least a part of the coil; two I-shaped cores which are arranged in the coil in parallel; an O-shaped core surrounding the coil and the coil mold; and a body mold molded from a second resin so as to cover at least a part of an assembly, the assembly being obtained by assembling the coil, the coil mold, the two I cores, and the O core, the coil mold including a first gap plate molded from the first resin mold, the first gap plate filling a gap between the two I cores, the body mold including a second gap plate molded from the second resin mold, the second gap plate filling a gap between each I core and the O core. According to this configuration, since the coil mold includes the first gap plate that fills the gap between the positions where the two I cores are arranged, the manufacturing cost can be reduced.

In the reactor, the first gap plate may be integrally formed with the coil mold, and the second gap plate may be integrally formed with the body mold. According to this structure, the manufacturing cost can be reduced.

In the above reactor, a gap between the two I cores may be a thickness of the first gap plate in the two I core parallel directions, and a gap between each of the I cores and the O core may be a thickness of the second gap plate in the two I core parallel directions. With this configuration, the accuracy of the gap between the I cores can be improved, and the magnetic field characteristics can be improved.

In the reactor, the first resin and the second resin may be made of the same material. With this configuration, the manufacturing cost can be reduced.

In the reactor, each of the I cores may be surrounded by the coil mold and the body mold. With this configuration, the manufacturing cost can be reduced.

According to the present embodiment, a method of manufacturing a reactor and a reactor that can reduce manufacturing costs can be provided.

Drawings

Features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, in which like reference numerals represent like elements, and wherein:

fig. 1 is a flowchart illustrating a manufacturing method of a reactor according to a comparative example.

Fig. 2 is a perspective view illustrating a coil in the manufacturing method of the reactor according to the comparative example.

Fig. 3 is a perspective view illustrating a coil mold in a manufacturing method of a reactor according to a comparative example.

Fig. 4 is a perspective view illustrating two I cores arranged in parallel with a gap therebetween in the method of manufacturing a reactor according to the comparative example.

Fig. 5 is a perspective view illustrating a gap plate filling a gap between I cores in the manufacturing method of the reactor according to the comparative example.

Fig. 6 is a perspective view illustrating the I-core S/a in the manufacturing method of the reactor according to the comparative example.

Fig. 7 is a perspective view illustrating an O core in the manufacturing method of the reactor according to the comparative example.

Fig. 8 is a perspective view illustrating an assembly in which a coil, a coil mold, and an I-core S/A, O core are assembled in a method of manufacturing a reactor according to a comparative example.

Fig. 9 is a perspective view illustrating the I core S/a arranged inside the O core in the method of manufacturing a reactor according to the comparative example.

Fig. 10 is a perspective view illustrating a reactor in the manufacturing method of the reactor according to the comparative example.

Fig. 11 is a cross-sectional view illustrating two I cores disposed inside an O core.

Fig. 12 is a flowchart illustrating a method of manufacturing a reactor according to embodiment 1.

Fig. 13 is a perspective view illustrating a coil mold in the method of manufacturing a reactor according to embodiment 1.

Fig. 14 is a sectional perspective view illustrating a coil mold in the method of manufacturing a reactor according to embodiment 1, and shows a section of the XIV-XIV line in fig. 13.

Fig. 15 is a sectional perspective view illustrating an assembly from which a coil is removed in the method of manufacturing a reactor according to embodiment 1.

Fig. 16 is a perspective cross-sectional view of a main body mold illustrating a method of manufacturing a reactor according to embodiment 1.

Fig. 17 is a perspective view illustrating a method of injecting resin in a body molding step in the method of manufacturing a reactor according to embodiment 1.

Fig. 18 is a cross-sectional view illustrating a method of injecting resin in a main body molding step in the method of manufacturing a reactor according to embodiment 1.

Fig. 19 is a diagram illustrating a result of CAE flow analysis when resin is injected into an assembly in the method for manufacturing a reactor according to embodiment 1.

Fig. 20 is a perspective view illustrating a reactor in the method of manufacturing a reactor according to embodiment 1.

Fig. 21 is a cross-sectional view illustrating a pin inserted between each I core and O core in the method of manufacturing a reactor according to embodiment 2.

Detailed Description

The present invention will be described below with reference to embodiments thereof, but the invention according to the scope of the claims is not limited to the embodiments below. Note that all the configurations described in the embodiments are not limited to the methods necessary for solving the problems. For clarity of description, the following description and drawings are appropriately omitted and simplified. In the drawings, the same elements are denoted by the same reference numerals, and repetitive description is omitted as necessary.

(embodiment mode 1)

A reactor and a method of manufacturing the reactor according to embodiment 1 will be described. The reactor is a passive element using a coil, and is used for applications (for example, a voltage converter) such as suppression of a high-frequency current, smoothing of a direct current, and boosting of a direct current voltage. The reactor is also referred to as an inductor.

The reactor of the present embodiment can be used for a power converter mounted in a hybrid vehicle or an electric vehicle, for example. Hybrid vehicles and electric vehicles have an ac motor such as an induction motor or a PM motor as a motor for traveling. Therefore, these vehicles are equipped with a power control unit including a voltage conversion circuit that boosts the direct current of the battery and an inverter circuit that converts the direct current into an alternating current of a frequency suitable for driving the running motor. For example, the reactor of the present embodiment may be used in a voltage conversion circuit of a power control unit. The application of the reactor of the present embodiment is not limited to a power converter mounted in a hybrid vehicle or an electric vehicle.

Before describing the configuration of the reactor according to embodiment 1, first, a method for manufacturing the reactor according to the comparative example and problems will be described. Hereinafter, a method of manufacturing the reactor of the present embodiment will be described in comparison with a comparative example. Thus, the characteristics of the reactor manufacturing method of the present embodiment are clarified. Next, a reactor of the present embodiment will be described.

< method for manufacturing reactor of comparative example >

Fig. 1 is a flowchart illustrating a manufacturing method of a reactor according to a comparative example. As shown in fig. 1, the manufacturing method of the reactor according to the comparative example includes a coil molding process, an I-core gap plate joining process, and a body molding process.

First, a coil molding process for forming a coil mold will be described. Fig. 2 is a perspective view of a coil exemplified in a manufacturing method of a reactor according to a comparative example. Fig. 3 is a perspective view illustrating a coil mold in a manufacturing method of a reactor according to a comparative example. In fig. 2 and 3, the side and end faces of the coil 110 are shaded so that the coil 110 and the coil mold 120 can be distinguished from each other.

As shown in step S11 of fig. 1 and fig. 2, the coil 110 is prepared. The coil 110 is formed by winding a strip-shaped or wire-shaped conductor into a predetermined shape, for example. The conductor includes copper, for example, but is not limited to copper as long as a current flows through the conductor. The conductor is, for example, a flat wire. The conductor is not limited to a flat wire, and may be a round wire having a round cross section.

The coil 110 is, for example, cylindrical, and a core member or air is disposed in the coil 110. The coil 110 is, for example, a round tube shape with rounded corners, but is not limited thereto, and may be a rectangular tube shape, a cylindrical shape, or the like. The coil 110 may have a terminal 112 extending in a predetermined direction.

Next, as shown in step S12 of fig. 1 and fig. 3, the coil mold 120 is formed. The coil mold 120 is formed by molding a resin so as to cover at least a part of the coil 110. Examples of the resin used include epoxy resin and silicone resin, but the resin is not limited to epoxy resin and silicone resin as long as it is a resin that is injected in a liquid state into a mold and then cured. Further, the resin may contain a filler.

The coil mold 120 is formed in the following order, for example. That is, the coil 110 is disposed inside a predetermined mold, not shown. Resin is injected into the interior of the mold in which the coil 110 is disposed. Then, the resin is cured. This enables the coil mold 120 molded with resin to be formed so as to cover at least a part of the coil 110. For example, the coil mold 120 covers the coil 110 in a ring shape along the peripheral edges of both ends of the coil 110, and covers the outer and inner surfaces of two facing sides among the four sides of the coil 110.

Next, an I core-gap plate joining process for joining the I core and the gap plate will be described. Fig. 4 is a perspective view illustrating two I cores arranged in parallel with a space therebetween in the method of manufacturing a reactor according to the comparative example. Fig. 5 is a perspective view illustrating a gap plate filling a gap between I cores in the manufacturing method of the reactor according to the comparative example. Fig. 6 is a perspective view illustrating an I-core S/a in a manufacturing method of a reactor according to a comparative example.

As shown in step S13 of fig. 1 and fig. 4 and 5, the I-core 130 and the gap plate 135 are prepared. The I core 130 is a rectangular parallelepiped I-shaped member. The I-core 130 is disposed within the coil 110 and controls the inductance of the coil 110. The I-core 130 includes, for example, a magnetic body that improves the inductance of the coil 110. A plurality of I cores 130 are disposed in the coil 110. For example, two I cores 130 are arranged in parallel in the coil 110.

Here, from the viewpoint of convenience in explaining the method of manufacturing the reactor, an XYZ rectangular coordinate system is introduced. The direction in which the two I cores 130 are juxtaposed is set as the X-axis direction. The vertical direction is defined as the Z-axis direction. The direction orthogonal to the X axis and the Z axis is the Y axis direction. The XYZ rectangular coordinate system is used for convenience, and is not limited to the orientation when an actual reactor is used, and is not limited to the orientation when an actual reactor is manufactured.

The gap plate 135 is a thin plate-like member. The gap plate 135 is disposed between the two I-cores 130. Thus, the thickness of the gap plate 135, i.e., the length of the gap plate 135 in the X-axis direction, corresponds to the gap between the two I cores 130. The gap plate 135 is a member that fills the gap between the two I cores 130. The gap plate 135 contains, for example, resin.

Next, as shown in step S14 of FIG. 1 and FIG. 6, an I-Core assembly (I Core Sub Assy, hereinafter referred to as I Core S/A136) is formed. The I-core S/a 136 is formed by joining two I-cores 130 with a gap plate 135 therebetween in the X-axis direction. In this way, the gap between the two I-cores 130 is filled by the gap plate 135.

The body molding step of forming a body mold is as follows. Fig. 7 is a perspective view illustrating an O core in a manufacturing method of a reactor according to a comparative example. Fig. 8 is a perspective view illustrating an assembly in which a coil, a coil mold, and an I-core S/A, O core are assembled in a method of manufacturing a reactor according to a comparative example. Fig. 9 is a perspective view illustrating an I core S/a arranged inside an O core in the manufacturing method of the reactor according to the comparative example. Fig. 10 is a perspective view illustrating a reactor in a manufacturing method of the reactor according to the comparative example.

As shown in step S15 of fig. 1 and fig. 7, the O-core 140 is prepared. The O-core 140 is an O-shaped member such as a corner fillet or an O-shape, and has a cavity formed therein. The O-core 140 is a component that can surround the I-core S/a 136 and the coil mold 120. That is, the two I cores 130 and the coil mold 120 can be arranged in the cavity portion formed in the O core 140.

Next, as shown in step S16 of fig. 1 and fig. 8, the assembly 150 is formed. The assembly 150 is formed by assembling the coil 110, the coil mold 120, the I core S/A136, and the O core 140. The coil 110 is disposed such that the cavity extends in the X-axis direction. The coil mold 120 is fixed in such a manner as to cover a portion of the coil 110. The I-core S/A136 is disposed within the coil 110. Two of the I-cores 130 in the I-core S/A136 are juxtaposed in the X-axis direction. The O-core 140 is disposed in an O-shape when viewed from the Z-axis direction. The O-core 140 is disposed so as to surround the I-core S/a 136 and the coil mold 120 located in the cavity.

As shown in fig. 9, when the positional relationship of the I core S/a 136 and the O core 140 is observed with the coil 110 and the coil mold 120 omitted, the O core 140 is arranged so as to surround the I core S/a 136. In the comparative example, the gap between the I-cores 130 corresponds to the thickness of the gap plate 135.

Next, as shown in step S17 of fig. 1 and fig. 10, the body mold 160 is formed. The main body mold 160 is formed by molding a resin so as to cover at least a part of the assembly 150. The resin used may be, for example, epoxy resin or silicone resin, as in the case of the coil mold 120, but the resin is not limited to epoxy resin or silicone resin as long as it is a resin that is injected in a liquid state into a mold and then cured. Further, the resin may contain a filler. The resin used for the body mold 160 and the resin used for the coil mold 120 may be made of the same material or different materials.

The body mold 160 is formed, for example, by the following procedure. That is, the assembly 150 is disposed inside a predetermined mold, not shown. The resin is injected into the interior of the mold in which the assembly 150 is disposed. In injecting the resin, for example, the resin is injected so as to press the two I cores 130 from both outer sides in the X direction. Then, the resin is cured. Thus, the main body mold 160 in which the resin is molded can be formed so as to cover at least a part of the assembly 150. A body mold 160 surrounds the I-core S/a 136 and includes a gap plate between each I-core 130 and O-core 140. In this way, the reactor 101 of the comparative example can be manufactured.

Fig. 11 is a cross-sectional view illustrating two I cores 130 disposed inside an O core 140. In fig. 11, the coil 110, the coil mold 120, the gap plate 135, and the body mold 160 are omitted.

As shown in fig. 11, a gap Ga is provided between the I-core 130 and the I-core 130. Gaps Gb and Gc are provided between the I core 130 and the O core 140. The gap Ga is a length between the I-core 130 and the I-core 130 in the X-axis direction. The gaps Gb and Gc are lengths between the I core 130 and the O core 140 in the X axis direction. It is necessary to control the gaps Ga, Gb, and Gc to predetermined lengths to ensure magnetic field characteristics.

In the comparative example, it is assumed that in the case where the two I cores 130 are separately arranged inside the O core 140 without forming the I core S/a 136, it is difficult to set the predetermined gap Ga between the two I cores 130. This is because, when resin is injected into the mold from both outer sides in the X-axis direction, the pressure of the resin injected into the mold causes the I cores 130 to press against each other, and the gap Ga between the I cores 130 is set to 0. Therefore, it is necessary to form the I cores S/a 136 sandwiching the gap plate 135 in advance so that the gap between the two I cores 130 becomes the predetermined gap Ga. Thus, in the comparative example, the I-core-gap plate joining step for forming the I-core S/a 136 was necessary, and the increase in the manufacturing cost could not be suppressed.

< method for manufacturing reactor of the present embodiment >

Next, a method for manufacturing a reactor according to the present embodiment will be described. In the present embodiment, a gap plate that fills the gap between the two I cores is formed in the coil molding process.

Fig. 12 is a flowchart illustrating a method of manufacturing a reactor according to embodiment 1. As shown in fig. 12, the method of manufacturing a reactor according to the present embodiment includes a coil molding step and a body molding step.

First, a coil molding process for forming a coil mold will be described. Fig. 13 is a perspective view illustrating a coil mold in the method of manufacturing a reactor according to embodiment 1. Fig. 14 is a sectional perspective view of a coil mold illustrating the method of manufacturing a reactor according to embodiment 1, and shows a section of the XIV-XIV line of fig. 13.

As shown in step S21 of fig. 12, the coil 10 is prepared. The coil 10 is the same as the coil 110 in the comparative example. The coil 10 may also have terminals 12.

Next, as shown in step S22 of fig. 12 and fig. 13 and 14, the coil mold 20 is formed. The coil mold 20 is formed by molding a resin so as to cover at least a part of the coil 10. For example, the coil mold 20 covers the coil 10 in a ring shape along the peripheral edges of both ends of the coil 10, and covers the outer and inner surfaces of two facing sides among the four sides of the coil 10. In addition, the coil molding die 20 further includes gap plates 25 protruding from portions of both side surfaces of the coil 10 covering the inner surfaces. The gap Ga between the two I-cores 30 corresponds to the thickness of the gap plate 25 in the X-axis direction.

In this way, in the present embodiment, in the coil molding step, the gap plate 25 filling the gap between the positions where the two I cores are arranged is molded with resin. The resin used for the coil mold 20 may be the same as that used for the comparative example.

The mold for forming the coil mold 20 of the present embodiment is shaped to form the gap plate 25 between the positions where the two I cores are arranged. That is, the resin flows between the positions where the two I cores are arranged and is cured.

The coil mold 20 is formed in the same order as that of the comparative example. That is, the coil 10 is disposed inside the mold, not shown. The resin is pressed into the mold in which the coil 10 is disposed. Then, the resin is cured. Thus, the coil mold 20 in which the resin is molded can be formed so as to cover at least a part of the coil 10. At this time, the gap plate 25 is integrally formed with the coil mold 20.

Next, a body mold process for forming a body mold will be described. Fig. 15 is a sectional perspective view illustrating an assembly from which a coil is removed in the method of manufacturing a reactor according to embodiment 1. Fig. 16 is a perspective cross-sectional view of a main body mold illustrating a method of manufacturing a reactor according to embodiment 1. Fig. 17 is a perspective view illustrating a method of injecting resin in a body molding step in the method of manufacturing a reactor according to embodiment 1. Fig. 18 is a cross-sectional view illustrating a method of injecting resin in a main body molding step in the method of manufacturing a reactor according to embodiment 1. Fig. 19 is a diagram illustrating a result of CAE flow analysis when resin is injected into an assembly in the method for manufacturing a reactor according to embodiment 1. Fig. 20 is a perspective view illustrating a reactor in the method of manufacturing a reactor according to embodiment 1. In fig. 18, a part of the hatching is omitted so as not to complicate the drawing.

As shown in step S23 of fig. 12, the I core 30 and the O core 40 are prepared. The I core 30 and the O core 40 are the same as the I core 130 and the O core 140 in the comparative example.

Next, as shown in step S24 of fig. 12, the assembled body 50 is formed. The assembly 50 is formed by assembling the coil 10, the coil mold 20, the I core 30, and the O core 40. As shown in fig. 15, the assembly 50 excluding the coil 10 includes a coil mold 20, two I cores 30, and an O core 40. In the assembly 50, the coil mold 20 is fixed so as to cover a part of the coil 10. In addition, the coil mold 20 includes a gap plate 25. The gap between the I-cores 30 is defined by the gap plate 25. The two I cores 30 are arranged in parallel in the coil 10. The O-core 40 is disposed so as to surround the coil 10 and the coil mold 20.

Next, as shown in step S25 of fig. 12 and fig. 16, the body mold 60 is formed. The main body mold 60 is formed by molding a resin so as to cover at least a part of the assembly 50. For example, the body mold 60 covers the outer surface of the coil mold 20 and covers the outer surface of the O-core 40. Further, the body mold 60 covers the outer surface of the I-core 30 and covers the inner surface of the O-core 40. Further, the body mold 60 includes a gap plate 65 filling the gap between each I core 30 and the O core 40. Each gap plate 65 has the same thickness as the gap between the I core 30 and the O core 40 in the X axis direction.

In this way, in the body molding step of the present embodiment, the gap plate 65 filling the gap between each I core 30 and the O core 40 is molded with resin. The resin used for the body mold 60 may be the same as the coil mold 20. The resin used for the body mold 60 and the resin used for the coil mold 20 may also comprise the same material.

The mold for forming the body mold 60 of the present embodiment is shaped to form a gap plate 65 for filling the gap between the I core 30 and the O core 40. That is, the resin flows between the I-core 30 and the O-core 40 and is cured.

The body mold 60 is formed, for example, in the following order. That is, the assembly 50 is disposed inside the mold, not shown. The resin is injected into the interior of the mold in which the assembly 50 is disposed. In injecting the resin, for example, as shown in fig. 17, the resin is injected from four corners of the assembly 50 through the injection pipes 66. Then, the resin flows from the four corners along the side surfaces and the inner surface of the O-core 40. Then, the gap between the I-core 30 and the O-core 40 is buried. As shown in fig. 17 and 18, the resin injected into the assembly 50 is injected into the assembly 50 from both outer sides along the X-axis direction in which the two I cores 30 are juxtaposed. This is also shown by the following analysis result in fig. 19.

As shown in fig. 19, in the result of CAE (Computer Aided Engineering) flow analysis when resin is injected into the assembly 50, the injected resin flows more rapidly toward the outer side than the central portion. Thereby, the injected resin applies a force pushing from the outside to the inside in the X-axis direction to the two I cores 30. Thereby, the resin presses the I-cores 30 to the gap plates 25, and thus the gap Ga between the I-cores 30 can be defined by the thickness of the gap plates 25.

Next, the resin injected into the assembly 50 is cured. Thus, the main body mold 60 in which the resin is molded can be formed so as to cover at least a part of the assembly 50. In this step, the gap plate 65 is integrally formed with the main body mold 60. In this way, as shown in fig. 20, the reactor 1 of the present embodiment can be manufactured.

< construction of reactor in the present embodiment >

Next, a configuration of a reactor according to the present embodiment will be described. As shown in fig. 18 and 20, the reactor 1 of the present embodiment includes a coil 10, a coil mold 20, two I cores 30, an O core 40, and a body mold 60. The coil mold 20 is a member in which resin is molded so as to cover at least a part of the coil 10. The I cores 30 are arranged in parallel in the coil 10. The O-core 40 is disposed so as to surround the coil 10 and the coil mold 20. The main body mold 60 is a member obtained by molding resin so as to cover at least a part of an assembly 50 obtained by assembling the coil 10, the coil mold 20, the two I cores 30, and the O core 40.

Also, the coil mold 20 includes a gap plate 25 molded by resin filling the gap between the two I cores 30. Thereby, the gap plate 25 is integrally formed with the coil mold 20. That is, the gap plate 25 is joined to the coil mold 20 without a seam. The gap plate 25 defines the length of the gap Ga. Here, the gap Ga corresponds to the thickness of the gap plate 25 in the direction in which the two I cores 30 are juxtaposed.

The body mold 60 includes a gap plate 65 molded from resin that fills the gap between each I core 30 and the O core 40. Thereby, the gap plate 65 is integrally formed with the main body mold 60. That is, the gap plate 65 is joined to the body mold 60 without a seam. The gap plate 65 defines gaps Gb and Gc. Here, the gaps Gb and Gc correspond to the thickness of the gap plate 65 in the X-axis direction.

Next, effects of the reactor 1 and the method for manufacturing the reactor 1 according to the present embodiment will be described. In the present embodiment, the gap plate 25 that secures the gap Ga between the I-cores 30 is formed simultaneously with the coil molding die 20 in the coil molding process. Thus, the I-core-gap plate joining step as in the comparative example can be omitted. This can reduce the manufacturing cost.

In the body molding step, the I-core 30 can be pressed against the gap plate 25 of the coil mold 20 by the injection pressure of the resin. This can improve the accuracy of the length of the gap Ga.

Further, in the body molding step, the I-core 30 is pressed against the gap plate 25 of the coil mold 20 by the injection pressure of the resin, and thus the position of the I-core 30 is fixed. This improves the accuracy of the gaps Gb and Gc between the I core 30 and the O core 40.

In this way, the gap plates 25 and 65 that define the lengths of the gaps Ga, Gb, and Gc can be integrally molded with the coil mold 20 and the body mold 60, so that the manufacturing cost can be reduced. Further, since the accuracy of the lengths of the gaps Ga, Gb, and Gc can be improved, the magnetic field characteristics of the reactor 1 can be improved.

In order to secure inductance even in a high current region, the configuration of the reactor 1 for the inverter requires a multilayer gapping for suppressing leakage loss in response to a high current. When the position of the I-cores 30 in the coil 10 cannot be fixed at the time of resin injection, the gap Ga between the I-cores 30 cannot be managed.

In the comparative example, the gap plates 135 formed of resin were joined between the I-cores 130, thereby managing the gap Ga between the I-cores 130. In this comparative example, an I-core-gap plate joining process was required, and it was difficult to reduce the manufacturing cost.

In contrast, in the present embodiment, the gaps Ga, Gb, and Gc are managed by two steps, i.e., the coil molding step and the body molding step. This can eliminate the step of bonding the I-core and the gap plate, and reduce the manufacturing cost.

(embodiment mode 2)

Next, a reactor and a method for manufacturing the reactor according to embodiment 2 will be described. Fig. 21 is a sectional view of a pin inserted between each I core and O core in the method of manufacturing a reactor according to embodiment 2.

As shown in fig. 21, in the present embodiment, in the body molding step, a pin 70 is provided between each I core 30 and O core 40 of the assembly 50 disposed inside the mold 80. The pin 70 is movable. Then, each I-core 30 is pressed against the gap plate 25 by the pin 70. In this state, the resin is pressed into the assembly 50 to form the body mold 60. Then, the resin is cured. The pin 70 is pulled out at an appropriate timing during the curing of the resin. Thus, a main body mold for molding resin can be formed to cover at least a part of the assembly 50. The other steps are the same as those in the manufacturing method of embodiment 1. In this way, the reactor of the present embodiment can be manufactured.

According to the method of manufacturing a reactor of the present embodiment, since each I-core 30 is pressed against the gap plate 25 by the pin 70 in the body molding step, the accuracy of the gap Ga between the I-cores 30 can be improved. This improves the magnetic field characteristics of the reactor. Further, for example, even in the case where the injection pressure of the resin is reduced, the accuracy of the gap Ga can be improved. This can improve the degree of freedom of the resin injection conditions in the main body molding step. Other configurations and effects are included in the description of embodiment 1.

The present invention is not limited to the above-described embodiments, and can be appropriately modified within the scope not departing from the gist of the present invention. For example, the configuration in which the respective structures of embodiments 1 and 2 are assembled is also included in the scope of the technical idea of the present embodiment.