Reactor manufacturing method and reactor

Abstract

The invention provides a method for manufacturing a reactor and a reactor, wherein a molded core and a molded coil are firmly jointed, and a welding part of a bus bar and a lead wire is prevented from being damaged. A method for manufacturing a reactor includes: a bonding step of bonding a molded core and a molded coil with an adhesive; and a welding step in which the lead wire of the coil is connected to the bus bar fixed to the mold core by welding. The coil is attached to the leg portion. The bonding step includes: a coating step in which an adhesive is applied to the bonding surface of the leg portion of the core member and the inner peripheral surface of the yoke portion of the core member; a pressing step for pressing and spreading the applied adhesive; and a hardening step for hardening the adhesive. In the pressing step, the adhesive applied to the bonding surface is pressed and spread out to be extruded to at least one of the upper surface and the lower surface of the leg part, and extruded to at least one of the inner side surface of the leg part and the outer side surface opposite to the inner side surface of the leg part, which are the surfaces of the leg part facing each other, and the adhesive is attached to the molded coil.

Description

Technical Field

[0001] This invention relates to a method for manufacturing a reactor having a molded core and a molded coil, and to the reactor itself. Background Technology

[0002] Reactors are used in various applications such as office automation (OA) equipment, solar power systems, automobiles, and uninterruptible power supplies (UPS). A reactor is an electromagnetic component that converts electrical energy into magnetic energy for storage and release.

[0003] A reactor has a core and a coil. The core is a magnetic material and is ring-shaped. The coil is mounted on the core. Leads are drawn from the coil and connected to a busbar by soldering. This busbar is electrically connected to external equipment. Power is supplied to the coil from the external equipment via the busbar, causing the coil to generate magnetic flux. The core forms the magnetic path through which the magnetic flux generated by the coil passes.

[0004] To insulate the core from the coil, the core and coil are sometimes molded separately, and then the molded core and molded coil are combined to make a reactor. For example, a protrusion is provided in the molded core, and a corresponding recess is provided in the molded coil, so that the protrusion of the molded core and the recess of the molded coil are fitted together, thereby making a reactor.

[0005] Patent Document 1: Japanese Patent Application Publication No. 2023-094806

[0006] Due to dimensional tolerances and other reasons, a certain gap may remain even when the convex and concave parts are fitted together. On the other hand, reactors are sometimes installed in vibrating environments, such as automobiles. Therefore, if a reactor is installed in a vibrating environment, there is a risk that the molded core or molded coil may move by the amount of the gap, and excessive stress may be generated at the welded joint between the busbar and the lead wire due to vibration, resulting in damage. Summary of the Invention

[0007] The present invention was proposed to solve the above-mentioned problems. Its purpose is to provide a method for manufacturing a reactor and a reactor that can firmly connect the molded core and the molded coil and prevent damage to the welded part of the busbar and the lead wire.

[0008] The method for manufacturing the reactor of the present invention is characterized by comprising the following steps: a molding core manufacturing step, wherein at least a portion of a core component is molded using a core molding resin to form a pair of molding cores; a molding coil manufacturing step, wherein at least a portion of a coil is molded using a coil molding resin to form a molding coil; a bonding step, wherein the molding cores and the molding coils are joined using an adhesive; and a welding step, wherein the leads of the coils are connected to a busbar fixed to the molding cores by welding, wherein the core component has a plurality of feet and a yoke connecting the feet, and the coils are mounted on the feet; the bonding step comprises the following step: a coating step, applying a coating to… The adhesive is applied to the mating surface of the foot of the core component and the inner circumferential surface of the yoke of the core component or the molded coil opposite to the inner circumferential surface of the yoke; a pressing step is performed to spread the applied adhesive; and a hardening step is performed to harden the adhesive. In the pressing step, the adhesive applied to the mating surface is spread out, thereby extruding the adhesive to at least one of the upper and lower surfaces of the foot, and extruding the adhesive to at least one of the surfaces of the foot that are opposite to each other, namely the inner side surface of the foot and the opposite side surface of the inner side surface, namely the outer side surface, and the adhesive is attached to the molded coil.

[0009] The reactor of the present invention is characterized by comprising: a pair of molded cores, each covering at least a portion of the core components with a core molding resin; a molded coil, each covering at least a portion of the coil with a coil molding resin; an adhesive for joining the molded cores to the molded coil; and a busbar fixed to the molded cores and connected to the leads of the coil by welding, wherein the core components have a plurality of legs and a yoke connecting the legs, the coil being mounted on the legs, and the adhesive having: a core-joining portion disposed between the joint surfaces of the legs for joining the core components. The following components are provided: an X-direction limiting portion disposed between the inner circumferential surface of the yoke and the molded coil, engaging the inner circumferential surface with the molded coil; a Y-direction limiting portion disposed between at least one of the opposing surfaces of the foot (i.e., the inner side surface of the foot) and the opposite side of the inner side surface (i.e., the outer side surface), engaging the inner side surface or the outer side surface with the molded coil; and a Z-direction limiting portion disposed between at least one of the upper and lower surfaces of the foot and the molded coil, engaging the upper surface or the lower surface with the molded coil.

[0010] The effects of the invention

[0011] According to the present invention, a method for manufacturing a reactor and a reactor are available that can securely connect the molded core and the molded coil and prevent damage to the welded portion of the busbar and the lead wire. Attached Figure Description

[0012] Figure 1 It is a perspective view showing the overall structure of the reactor.

[0013] Figure 2 It is a perspective view showing the overall structure of the molded core.

[0014] Figure 3 This is a perspective view of the core component.

[0015] Figure 4 This is a perspective view of a molded coil.

[0016] Figure 5 This is a perspective view of the coil.

[0017] Figure 6 This is an enlarged view of the protruding part.

[0018] Figure 7 This is a schematic diagram showing the formation sites of the adhesive.

[0019] Figure 8 This diagram illustrates a method of applying adhesive to the mating surfaces. Detailed Implementation

[0020] [Implementation Method]

[0021] The reactor involved in the embodiment will be described with reference to the accompanying drawings. Figure 1 This is a perspective view showing the overall structure of the reactor 10. In the various figures, for ease of understanding, thickness, dimensions, positional relationships, proportions, or shapes are sometimes shown in an emphasized manner, but the invention is not limited by these emphasized manners.

[0022] In addition, the winding direction of coil 6 is Figure 1 The arrangement direction of the core component's feet is shown in the X direction. Figure 1 The Y-direction shown, also known as the width direction, is the direction orthogonal to both the roll direction and the width direction. Figure 1 The Z direction shown is also called the height direction.

[0023] The reactor 10 is an electromagnetic component that converts electrical energy into magnetic energy for storage and release, and is used in various applications such as OA equipment, solar power generation systems, and automobiles. The reactor 10 has a molded coil 5 and a pair of molded cores 1a and 1b.

[0024] Figure 2 This is a perspective view showing the overall structure of the molded cores 1a and 1b. The molded cores 1a and 1b are made by molding the core components 21 and 22 that constitute the core 2 using core molding resin 3.

[0025] Core 2 can use pressed powder cores, ferrite cores, laminated steel plates, or metal composite cores. Metal composite cores are magnetic materials formed by mixing magnetic powder and resin and then hardening the resin.

[0026] Core 2 consists of a pair of core components 21 and 22. Core components 21 and 22 are of the same shape and size. Figure 3 This is a perspective view of the core component 21. The core component 21 has a U-shaped form with a pair of legs 23 extending along the spool direction and a yoke 24 connecting the pair of legs 23. A coil 6 is mounted on the legs 23.

[0027] The front end face of the foot 23 has a mating surface 231, an inner curved surface 232, and an outer curved surface 233. The front end face of the foot 23 is an end face orthogonal to the spool direction and is the end face opposite to the one connected to the yoke 24. The mating surface 231 is a flat surface. The mating surface 231 is located further inside the curved surface 232 than the center position in the width direction (Y direction) of the foot 23. That is, the center position in the width direction of the mating surface 231 is located further inside the curved surface 232 than the center position in the width direction of the foot 23. By mating the mating surfaces 231 of the core components 21 and 22, the core 2 becomes an annular ring. The core 2 becomes a closed magnetic circuit through which the magnetic flux generated by the coil 6 passes.

[0028] Furthermore, in this embodiment, a spacer 25 is provided between the mating surfaces 231 of the core components 21 and 22 (see reference). Figure 2 The spacer 25 can be made of non-magnetic materials, ceramics, non-metals, resins, carbon fibers, or a combination of two or more of these materials, or spacer paper. As described above, by joining the core components 21 and 22 with the spacer 25 in between, a magnetic gap of a specified width is provided to prevent a decrease in the inductance of the reactor 10. Alternatively, the core components 21 and 22 can be joined directly with an adhesive without a gap.

[0029] An inner curved surface 232 is disposed at the inner corner of the front end face of the foot 23. The inner curved surface 232 is positioned between the mating surface 231 and the inner side surface 236 (described later), connecting the mating surface 231 and the inner side surface 236. The inner curved surface 232 is curved. An outer curved surface 233 is disposed at the outer corner of the front end face of the foot 23. The outer curved surface 233 is positioned between the mating surface 231 and the outer side surface 237 (described later), connecting the mating surface 231 and the outer side surface 237. In other words, the mating surface 231 is positioned between the inner curved surface 232 and the outer curved surface 233. The bending radius of the inner curved surface 232 is smaller than that of the outer curved surface. That is, compared to the inner curved surface 232, the outer curved surface 233 curves more gently. Furthermore, the surface area of ​​the inner curved surface 232 is smaller than that of the outer curved surface 233. Furthermore, the inner side refers to the direction towards the center of the reactor 10, and the outer side refers to the direction away from the center of the reactor 10.

[0030] The foot portion 23 has an upper surface 234 and a lower surface 235 orthogonal to the height direction. Both the upper surface 234 and the lower surface 235 are flat surfaces. The upper surface 234 and the lower surface 235 are connected to the mating surface 231, respectively. Additionally, the foot portion 23 has an inner side surface 236 and an outer side surface 237 orthogonal to the width direction. The inner side surface 236 is a pair of opposing surfaces of the foot portion 23, and the outer side surface 237 is the surface opposite to the inner side surface 236. Both the inner side surface 236 and the outer side surface 237 are flat surfaces. The inner side surface 236 is connected to the inner curved surface 232. The outer side surface 237 is connected to the outer curved surface 233.

[0031] The yoke 24 connects a pair of legs 23. The yoke 24 is covered by core molding resin 3. However, the inner circumferential surface 241 of the yoke 24 is not covered by core molding resin 3 and is exposed. The inner circumferential surface 241 of the yoke 24 is a surface orthogonal to the spool and is the surface opposite to the annular surface 61 of the coil 6 (the surface formed between the legs 23).

[0032] return Figure 2 The core molding resin 3 is formed by molding the core components 21 and 22 separately. The core molding resin 3 is integral with the core components 21 and 22. Figure 2 As shown, a portion of the core components 21 and 22 is covered. In this embodiment, the core molding resin 3 only covers the yoke portion 24 of the core component 2. In other words, the foot portion 23 of the core component 2 is not covered by the core molding resin 3 and is exposed. In addition, the core molding resin 3 does not cover the inner peripheral surface 241 of the yoke portion 24, and the inner peripheral surface 241 is exposed.

[0033] The core molding resin 3 is composed of resin. Examples of resins used as the core molding resin 3 include epoxy resin, unsaturated polyester resin, polyurethane resin, BMC (Bulk Molding Compound), polyphenylene sulfide (PPS), PBT (Polybutylene Terephthalate), or combinations thereof. Additionally, thermally conductive fillers may be incorporated into the resin. In this embodiment, PPS is used as the core molding resin 3.

[0034] Furthermore, the molded core 1a has a busbar 4a. The busbar 4a is, for example, a plate-shaped conductive component such as copper or aluminum. The busbar 4a is covered by core molding resin 3 and fixed to the molded core 1a. The busbar 4a is connected to the lead wire 62 of the coil 6 by welding. In addition, the busbar 4a is connected to the connection terminal of an external device. The reactor 10 is electrically connected to the external device via the busbar 4a.

[0035] Figure 4 This is a perspective view of the molded coil 5. Figure 5 This is a perspective view of coil 6. Molded coil 5 has coil 6 and coil molding resin 7. Molded coil 5 is made by molding coil 6 into shape using coil molding resin 7.

[0036] The coil 6 is composed of a flat-angled conductive component that has been insulated with enamel or the like. The coil 6 is formed by winding the conductive component into a cylindrical shape while offsetting the winding position along the spool direction. In this embodiment, the coil is wound with the narrow side of a flat-angled wire made of copper wire. However, the type of wire or winding method of the coil 6 is not limited to this, and other methods may also be used.

[0037] Two coils 6 are provided. These two coils 6 are arranged laterally with their outer peripheral surfaces facing each other, extending along the spool. Each coil 6 has an annular surface 61 orthogonal to the spool. From each coil 6, a lead wire 62, serving as a conductive component, extends from one side of the annular surface 61. Each lead wire 62 is connected to busbars 4a and 4b by welding. The coils 6 are energized via busbars 4a and 4b, generating magnetic flux.

[0038] Furthermore, an upper surface cover 63, an inner circumferential surface cover 64, and a lower surface cover 65 are provided around the coil 6. The upper surface cover 63, inner circumferential surface cover 64, and lower surface cover 65 are made of resin. The upper surface cover 63 covers the upper surface of the coil 6. The inner circumferential surface cover 64 covers the inner circumferential surface of the coil 6 and one side of the annular surface 61. In this embodiment, the portion of the inner circumferential surface cover 64 that covers the inner circumferential surface of the coil 6 is not covered by the coil molding resin 8. That is, the inner circumference of the molded coil 5 is formed by the inner circumferential surface cover 64. The lower surface cover 65 covers the lower surface of the coil 6 and the other side of the annular surface 61. By covering the area around the coil 6 with the upper surface cover 63, inner circumferential surface cover 64, and lower surface cover 65, direct contact between the coil 6 and the mold, pressing parts, jigs, or sprayed resin is prevented during molding.

[0039] The coil molding resin 7 directly covers or covers the coil 6 through various covers 63, 64, and 65. The coil molding resin 7 is composed of resin. Examples of resins used as the coil molding resin 7 include epoxy resin, unsaturated polyester resin, polyurethane resin, BMC (Bulk Molding Compound), polyphenylene sulfide (PPS), PBT (Polybutylene Terephthalate), or composites thereof. Additionally, thermally conductive fillers may be incorporated into the resin.

[0040] Coil molding resin 7 Figure 4 As shown, the reactor 10 has a protrusion 71. Two protrusions 71 are provided. Each protrusion 71 is located on the end face of the coil molding resin 7, which is orthogonal to the spool. More specifically, the protrusion 71 is located between the annular surfaces 61 of a pair of coils 6. The protrusion 71 is located in the central portion in the height direction of the reactor 10. The protrusion 71 extends from the end face of the coil molding resin 7, which is orthogonal to the spool, toward the inner peripheral surface 241 of the yoke portion 24. That is, the protrusion 71 faces the inner peripheral surface 241 of the yoke portion 24.

[0041] Figure 6 This is an enlarged view of the protrusion 71. The protrusion 71 is in the shape of a rectangular flat plate, but is not limited to this. However, a plurality of grooves 72 are formed in the protrusion 71. The grooves 72 cut off the protrusion 71. The depth of the grooves 72 is shorter than the protruding length of the protrusion 71. In other words, the grooves 72 do not cut to the bottom surface of the protrusion 71, that is, they do not cut to the end face of the coil molding resin 7 where the protrusion 71 is not formed.

[0042] The groove 72 has multiple vertical grooves 721 and multiple horizontal grooves 722. The vertical grooves 721 extend along the height direction. The multiple vertical grooves 721 are arranged at equal intervals. In this embodiment, three vertical grooves 721 are formed. The horizontal grooves 722 extend along the width direction. That is, the horizontal grooves 722 are orthogonal to the vertical grooves 721 and extend in a crisscross manner. The multiple horizontal grooves 722 are arranged at equal intervals. In this embodiment, six horizontal grooves 722 are formed. As shown above, the protrusion 71 is formed into a grid shape by the vertical grooves 721 and the horizontal grooves 722.

[0043] Furthermore, the molded coil 5 has a busbar 4b. The busbar 4b is covered by coil molding resin 7 and is fixed to the molded coil 5. The busbar 4b is connected to the lead wire 62 of the coil 6 by welding. In addition, the busbar 4b is connected to the connection terminal of an external device.

[0044] The molded cores 1a and 1b and the molded coil 5 are fixed by adhesive 8. In this embodiment, epoxy resin is used as adhesive 8, but other adhesives may also be used. Figure 7 This is a schematic diagram showing the formation site of adhesive 8. Adhesive 8 is as follows... Figure 7 As shown, it has a core bonding portion 81, an X-direction limiting portion 82, a Y-direction limiting portion 83, and a Z-direction limiting portion 84. Furthermore, the core bonding portion 81, the X-direction limiting portion 82, the Y-direction limiting portion 83, and the Z-direction limiting portion 84 are formed by curing the adhesive 8 in the curing process described later.

[0045] A core joint 81 is formed between the mating surfaces 231 of the feet 23 of the core components 21 and 22. The core joint 81 abuts against each mating surface 231, joining the core components 21 and 22. In this embodiment, since there is a spacer 25 between each mating surface 231, the core joint 81 is formed between the mating surface 231 of the core component 21 and the spacer 25, and between the mating surface 231 of the core component 22 and the spacer 25. Therefore, the core joint 81 abuts against each mating surface 231 and the spacer 25, and the core components 21 and 22 are joined apart by the spacer 25.

[0046] An X-direction limiting portion 82 is formed between the inner peripheral surface 241 of the yoke portion 24 of the core components 21 and 22 and the protrusion 71 of the coil molding resin 7. The X-direction limiting portion 82 abuts against the inner peripheral surface 241 and the protrusion 71. The X-direction limiting portion 82 is also formed inside the vertical groove 721 and the horizontal groove 722 of the protrusion 71. The X-direction limiting portion 82 engages and fixes the inner peripheral surface 241 of the molded cores 1a and 1b with the protrusion 71 of the molded coil 5. Furthermore, the X-direction limiting portion 82 may also be formed to be larger than the protrusion 71.

[0047] A Y-direction limiting portion 83 is formed between at least one of the inner side surface 236 and the outer side surface 237 of the core components 21 and 22 and the inner peripheral surface of the molded coil 5 (the inner peripheral cover 64 that covers the inner peripheral surface of the coil 6). In this embodiment, the Y-direction limiting portion 83 is formed only on the inner side surface 236. The Y-direction limiting portion 83 abuts against the inner side surface 236 and the inner peripheral cover 64 of the core components 21 and 22. The Y-direction limiting portion 83 extends across the inner side surfaces of both core components 21 and 22. That is, the Y-direction limiting portion 83 also abuts against the inner curved surface 232 and the spacer 25 of the core components 21 and 22, and is also formed in the space defined by the inner curved surface 232, the spacer 25, and the inner peripheral cover 64 of the core components 21 and 22. The Y-direction limiting portion 83 engages and fixes the inner side surface 236 of the molded cores 1a and 1b with the inner peripheral cover 64 of the molded coil 5. In addition, the Y-direction limiting part 83 is connected to the core joint part 81.

[0048] A Z-direction limiting portion 84 is formed between at least one of the upper surface 234 and lower surface 235 of the core components 21 and 22 and the inner peripheral cover 64 that covers the inner peripheral surface of the coil 6. In this embodiment, the Z-direction limiting portion 84 is formed on both the upper surface 234 and lower surface 235 of the core components 21 and 22. The Z-direction limiting portion 84 abuts against the upper surface 234, lower surface 235 of the core components 21 and 22 and the inner peripheral cover 64. The Z-direction limiting portion 84 extends across the respective upper surface 234 and lower surface 235 of the core components 21 and 22. That is, the Z-direction limiting portion 84 also abuts against the upper and lower surfaces of the core joining portion 81 and the spacer 25. The Z-direction limiting portion 84 engages and fixes the upper surface 234 and lower surface 235 of the molded cores 1a and 1b to the inner peripheral cover 64 of the molded coil 5.

[0049] In this embodiment, the reactor 10 also includes a sensor 9. The sensor 9 measures physical quantities of the reactor 10. The sensor 9 can be, for example, a thermistor whose resistance changes in response to temperature changes. However, the sensor 9 is not limited to a thermistor and can also be a magnetic sensor, a current sensor, a thermal fuse, or other similar sensor.

[0050] [Manufacturing Method]

[0051] Next, the manufacturing method of the reactor 10 in this embodiment will be described. The manufacturing method of the reactor 10 includes a molding core manufacturing process, a molding coil manufacturing process, a bonding process, and a welding process.

[0052] The molding core manufacturing process involves creating molding cores 1a and 1b through molding. Core component 21 is housed in a mold, and core molding resin 3 is sprayed into the mold. Then, molding core 1a is created by hardening the core molding resin 3. Similarly, core component 22 is housed in a mold, core molding resin 3 is sprayed into the mold, and molding core 1b is created by hardening the core molding resin 3. Furthermore, during the manufacturing of molding core 1a, busbar 4a is also housed in the mold and molded together with core component 21, thereby fixing busbar 4a to molding core 1a.

[0053] The molding coil manufacturing process involves creating the molded coil 5 through molding. The coil 6 and the busbar 4b are housed in a mold, and coil molding resin 7 is sprayed into the mold. Then, the molded coil 5 is manufactured by hardening the coil molding resin 7.

[0054] Furthermore, regarding the molding core manufacturing process and the molding coil manufacturing process, either process can be performed in the first place. Additionally, the molding core manufacturing process and the molding coil manufacturing process can be performed simultaneously in parallel.

[0055] The bonding process is the process of joining and fixing the molded cores 1a and 1b and the molded coil 5 using adhesive 8. The bonding process includes an application process, a pressing process, and a hardening process.

[0056] The coating process is the process of applying adhesive 8 to the molded cores 1a, 1b and the molded coil. First, adhesive 8 is applied to the inner peripheral surface 241 of the yoke portion 24 of the molded core 1a and the mating surface 231 of the foot portion 23. Figure 8 This diagram illustrates the method of applying adhesive 8 to the mating surface 231. (See diagram for example.) Figure 8 As shown, adhesive 8 is applied to the central portion of the mating surface 231, near the edge of the upper surface 234 side of the foot 23, near the edge of the lower surface 235 side, and near the edge of the inner side surface 236 side. The amount of adhesive 8 applied to the mating surface 231 is such that, by pressing, the adhesive 8 applied to the mating surface 231 can be extruded onto the upper surface 234, lower surface 235, and inner side surface 236 of the foot 23, and fills the gap between the upper surface 234, lower surface 235, and inner side surface 236 of the foot 23 and the inner peripheral surface of the molded coil 5.

[0057] Then, the molded coil 5 is inserted into the foot 23 of the molded core 1a. At this time, the adhesive 8 applied to the inner circumferential surface 241 of the molded core 1a adheres to the protrusion 71 of the molded coil 5. After the molded coil 5 is inserted into the designated position, the spacer 25 is inserted into the inner circumference of the molded coil 5, so that it adheres to the adhesive 8 applied to the mating surface 231.

[0058] Finally, adhesive 8 is applied to the inner peripheral surface 241 of the yoke portion 24 of the molded core 1b and the mating surface 231 of the foot portion 23. The application of adhesive 8 to the mating surface 231 is the same as that to the molded core 1a. Figure 8 As shown, adhesive 8 is applied to the central portion of the mating surface 231, near the edge of the upper surface 234 side of the foot 23, near the edge of the lower surface 235 side, and near the edge of the inner side surface 236 side. Then, the molded core 1b is inserted into the molded coil 5. The molded core 1b is inserted until the adhesive 8 applied to the inner peripheral surface 241 of the molded core 1b adheres to the protrusion 71 of the molded coil 5.

[0059] Once the insertion of the molded core 1b into the molded coil 5 is complete, the process proceeds to the pressing step. The pressing step involves pressing the molded cores 1a and 1b to spread the adhesive 8. For the molded cores 1a and 1b, the back side (the side opposite to the inner circumferential surface 241) of the yoke portion 24 is pressed along the spool direction. Through pressing, the adhesive 8 applied to the mating surface is spread out in such a way that it adheres to the entire mating surface 231.

[0060] By further pressing, the adhesive 8 applied to the mating surface 231 is extruded from the mating surface 231 toward the upper surface 234, lower surface 235, and inner side surface 236 of the foot 23. The extruded adhesive 8 extends into the space between the upper surface 234 or lower surface 235 and the inner peripheral surface of the molded coil 5, adhering to the upper surface 234, lower surface 235, and the inner peripheral surface of the molded coil 5. In addition, the extruded adhesive 8 fills the space between the inner curved surface 232 and the inner peripheral surface of the molded coil 5, extends into the space between the inner side surface 236 and the molded coil 5, and adheres to the inner side surface 236 and the inner peripheral surface of the molded coil 5. Furthermore, the adhesive 8 applied to the inner peripheral surface 241 of the yoke 24 is pressed and spread on the inner peripheral surface 241, and enters the vertical groove 721 and horizontal groove 722 of the protrusion 71.

[0061] After the pressing process, the process proceeds to the curing process. The curing process involves drying and hardening the adhesive 8. For example, the adhesive 8 is hardened by heating it. The optimal temperature or time for heating can be selected based on the material of the adhesive. As a result, the adhesive 8 hardens, forming the core joint 81, the X-direction limiting part 82, the Y-direction limiting part 83, and the Z-direction limiting part 84. Through the core joint 81, the core components 21 and 22 are joined to form a ring-shaped core 2. Furthermore, through the X-direction limiting part 82, the Y-direction limiting part 83, and the Z-direction limiting part 84, the molded cores 1a and 1b and the molded coil 5 are joined and fixed.

[0062] The welding process is a process of joining the lead wire 62 of coil 6 with the busbars 4a and 4b by welding. Through the welding process, the lead wire 62 and the busbars 4a and 4b are fixed in a connected state.

[0063] [Effects]

[0064] As described above, the reactor 10 of this embodiment includes: a pair of molded cores 1a and 1b, which cover at least a portion of core components 21 and 22 with core molding resin 3; a molded coil 5, which covers at least a portion of coil 6 with coil molding resin 7; an adhesive 8, which bonds the molded cores 1a and 1b to the molded coil 5; and a busbar 4a, which is fixed to the molded core 1a by welding to the lead wire 62 of the coil 6. The core components 21 and 22 have a plurality of feet 23 and a yoke 24 connecting the feet 23. The coil 6 is mounted on the feet 23. The adhesive 8 includes: a core joining portion 81 disposed between the joining surfaces 231 of the foot portion 23 to join the core components 21 and 22; an X-direction limiting portion 82 disposed between the inner peripheral surface 241 of the yoke portion 24 and the molded coil 5 to join the inner peripheral surface 241 and the molded coil 5; a Y-direction limiting portion 83 disposed between the inner side surface 236 of the foot portion 23 and the molded coil 5 to join the inner side surface 236 and the molded coil 5; and a Z-direction limiting portion 84 disposed between the upper surface 234 and the lower surface 235 of the foot portion 23 and the molded coil 5 to join the upper surface 234 or the lower surface 235 to the molded coil 5.

[0065] As described above, the molded cores 1a and 1b and the molded coil 5 are restricted from moving in the X direction (reel direction) by the X-direction restriction part 82, from moving in the Y direction (width direction) by the Y-direction restriction part 83, and from moving in the Z direction (height direction) by the Z-direction restriction part 84. That is, the molded cores 1a and 1b and the molded coil 5 are fully engaged in three axial directions by the X-direction restriction part 82, the Y-direction restriction part 83, and the Z-direction restriction part 84, thus restricting their movement. Therefore, even if the reactor 10 is mounted in an environment that generates vibration, movement of the molded cores 1a and 1b or the molded coil 5 can be suppressed, and damage caused by excessive stress at the weld between the lead wire 62 and the busbar 4a fixed to the molded core 1a can be prevented. Furthermore, although the molded core 1b does not have a busbar, the molded core 1b is engaged with the molded core 1a through the core joint 81. If the molded core 1b moves due to vibration, it may also affect the molded core 1a. Therefore, it is preferable that the molded core 1b also engages the molded coil 5 in three axial directions to restrict movement.

[0066] When coil 6 is not molded from coil molding resin 8, even if vibration is applied to the reactor, coil 6 itself is spirally wound, thus acting as a spring to absorb vibration and thereby mitigating stress generated at the weld joint to some extent. On the other hand, as in this embodiment, when coil 6 is molded from coil molding resin 8, coil 6 loses its elasticity, and therefore cannot absorb vibration on its own, easily generating stress at the weld joint. In addition, coil 6 itself becomes a heavy block due to coil molding resin 8, thus increasing the stress generated at the weld joint. However, as in this embodiment, by being bonded in all three axial directions by adhesive 8, the movement of the molding cores 1a, 1b and the molding coil 5 is restricted, thereby suppressing excessive stress generated at the weld joint due to vibration.

[0067] Furthermore, the Y-direction limiting portion 83 is disposed between the inner side surface 236 and the molded coil 5. That is, the Y-direction limiting portion 83 is formed closer to the center of gravity of the reactor 10, thus increasing rigidity and effectively preventing damage caused by excessive stress generated in the weld due to vibration. In addition, when the center of the coil 6 becomes hot, the Y-direction limiting portion 83 also functions as a heat dissipation path, thereby improving the heat dissipation of the reactor 10.

[0068] The manufacturing method of the reactor 10 in this embodiment includes the following steps: a molding core manufacturing step, in which core components 21 are molded using core molding resin 3 to form a pair of molding cores 1a and 1b; a molding coil manufacturing step, in which coil 6 is molded using coil molding resin 7 to form a molding coil 5; a bonding step, in which molding cores 1a and 1b and molding coil 5 are joined using adhesive 8; and a welding step, in which the lead wire 62 of coil 6 is connected to the busbar 4a fixed to molding core 1a by welding. Core components 21 and 22 have a plurality of feet 23 and a yoke 24 connecting the feet 23, and coil 6 is mounted on the feet 23. The bonding process includes: a coating process, in which adhesive 8 is applied to the mating surfaces 231 of the feet 23 of the core components 21 and 22 and the inner peripheral surfaces 241 of the yokes 24 of the core components 21 and 22; a pressing process, in which the applied adhesive 8 is pressed out; and a hardening process, in which the adhesive 8 is hardened. In the pressing process, by pressing out the adhesive 8 applied to the mating surfaces 231, the adhesive 8 is extruded to both the upper surface 234 and the lower surface 235 of the feet, and also to the inner side surface 236 of the feet 23, thus adhering the adhesive 8 to the molded coil 5.

[0069] As described above, by pressing the adhesive 8 applied to the joint surface 231, it is extruded onto the upper surface 234, lower surface 235, and inner side surface 236 of the foot 23. Therefore, compared to applying it to each part individually, productivity is improved. Furthermore, in this embodiment, the adhesive 8 is extruded onto both the upper surface 234 and the lower surface 235 of the foot 23, but it is sufficient to extrude it onto at least one of the upper surface 234 and the lower surface 235. In such a structure, the molded cores 1a and 1b and the molded coil 5 can also be fixed, which can suppress the excessive stress generated at the weld between the lead wire 62 and the busbar 4a fixed to the molded core 1a due to vibration.

[0070] The coil molding resin 7 has a protrusion 71 that faces the inner peripheral surface 241 of the yoke 24 and protrudes toward the inner peripheral surface 241. The protrusion 71 has a groove 72, and an X-direction limiting part 82 abuts against the protrusion 71 and is formed inside the groove 72.

[0071] Therefore, the X-direction limiting portion 82 increases the surface area in contact with the coil molding resin 7. Consequently, the bonding strength between the molding cores 1a and 1b and the molding coil 5 is improved. As a result, stress generated at the weld between the lead wire 62 and the busbar 4a due to vibration can be effectively suppressed.

[0072] The coil molding resin 7 is composed of polyphenylene sulfide (PPS), and the adhesive 8 is epoxy resin. PPS and epoxy resin have poor compatibility, and there is a tendency for the adhesive strength to weaken. However, in this embodiment, a groove 72 is provided in the protrusion 71, allowing the adhesive 8 to enter the interior of the groove 72, and forming an X-direction limiting part 82 inside the groove 72. Therefore, even with materials with poor compatibility, the molding cores 1a and 1b can be firmly bonded to the molding coil 5 by the inner peripheral surface 241 of the yoke 24 and the protrusion 71 of the coil molding resin 7, thus limiting movement in the X direction.

[0073] Specifically, in this embodiment, the groove 72 is formed by a plurality of vertical grooves 721 and a plurality of horizontal grooves 722, and the protrusion 71 is in a grid pattern. Therefore, the X-direction limiting portion 82 can further improve the bonding strength between the molded cores 1a and 1b and the molded coil 5 realized by the X-direction limiting portion 82.

[0074] [Other Implementation Methods]

[0075] This specification describes embodiments of the invention, but these embodiments are merely illustrative and do not limit the scope of the invention. Such embodiments can be implemented in various other ways, and various omissions, substitutions, and modifications can be made without departing from the scope of the invention. The embodiments or variations thereof are included within the scope or spirit of the invention, and similarly within the scope of the claims and their equivalents.

[0076] In the above embodiment, the Y-direction limiting portion 83 is formed between the inner side surface 236 and the molded coil 5, but it can also be formed between the outer side surface 237 and the molded coil 5. Even with this configuration, the outer side surface 237 of the molded coils 1a and 1b and the molded coil 5 can be joined by the Y-direction limiting portion 83, thereby limiting the movement of the molded cores 1a and 1b and the molded coil 5 in the Y direction (width direction). In addition, by providing the Y-direction limiting portion 83 on the outer side surface 237 side, when observing the coil 6 from the annular surface 61 of the coil 6 along the spool direction during the pressing process, it is possible to confirm whether the adhesive 8 has been squeezed into the gap between the outer side surface 237 and the inner peripheral surface (inner peripheral surface cover 64) of the molded coil 5.

[0077] Alternatively, the Y-direction limiting portion 83 can be formed on both the inner side surface 236 and the outer side surface 237. This allows both the inner side surface 236 and the outer side surface 237 to be joined with the molded coil 5, thereby increasing the bonding strength.

[0078] In the above embodiment, when forming the X-direction limiting portion 82, the adhesive 8 is applied to the inner peripheral surface 241 of the yoke portion 24. However, it is also possible to apply the adhesive to the molded coil 5 opposite to the inner peripheral surface 241 instead of the inner peripheral surface 241. That is, the adhesive may also be applied to the protrusion 71 of the molded coil 5.

[0079] Alternatively, the protrusion 71 can be provided on the molded coils 1a and 1b. For example, the inner peripheral surface 241 of the yoke 24 can be covered with the core molding resin 3. Furthermore, the protrusion 71 protruding toward the annular surface 61 of the coil 6 can also be provided on the core molding resin 3.

[0080] In the above embodiment, in addition to applying the adhesive 8 to the central portion of the mating surface 231, it is also applied to the vicinity of the edge of the upper surface 234, the edge of the lower surface 235, and the edge of the inner side surface 236 of the mating surface 231. However, as long as the adhesive 8 is squeezed out to the upper surface 234, the lower surface 235, and the inner side surface 236 of the foot 23, it may only be applied to the central portion.

[0081] In the above embodiment, the busbar 4a is molded and covered by the core molding resin 3, but the method of fixing the busbar 4a to the molding core 1a is not limited to this. For example, a terminal block with the busbar 4a can be manufactured separately from the molding core 1a, and the terminal block can be fixed to the molding core 1a by bolts or other fixing tools. Even with such a structure, movement of the molding cores 1a, 1b or the molding coil 5 can be suppressed, and damage caused by excessive stress at the welded part between the lead wire 62 and the busbar 4a can be prevented.

[0082] Explanation of the label

[0083] 10 Reactors

[0084] 1a, 1b Molded cores

[0085] 2 cores

[0086] 21-core components

[0087] 22-core components

[0088] 23. Feet

[0089] 231 Joint surface

[0090] 232 Inner curved surface

[0091] 233 Outer curved surface

[0092] 234 Upper surface

[0093] 235 Lower surface

[0094] 236 Inner side

[0095] 237 Outer side

[0096] 24. Magnetic yoke

[0097] 241 Inner circumferential surface

[0098] 25 spacers

[0099] 3-core molding resin

[0100] Busbars 4a and 4b

[0101] 5. Molded coils

[0102] 6 coils

[0103] 61. Annular surface

[0104] 62 Lead wires

[0105] 63. Top cover

[0106] 64 Inner circumferential cover

[0107] 65 Lower surface cover

[0108] 7. Coil molding resin

[0109] 71 Protrusion

[0110] 72 slots

[0111] 721 Vertical groove

[0112] 722 Horizontal slot

[0113] 8. Adhesive

[0114] 81 Core Joint

[0115] 82 X-direction restriction section

[0116] 83 Y-direction restriction section

[0117] 84 Z-direction restriction section

[0118] 9 sensors

Claims

1. A method for manufacturing a reactor, characterized in that, It includes the following processes: The molding core manufacturing process involves molding at least a portion of a core component using core molding resin to create a pair of molded cores. The molding coil manufacturing process involves molding at least a portion of a coil into shape using coil molding resin to create a molded coil. The bonding process involves using an adhesive to join the molded core to the molded coil. as well as The welding process connects the leads of the coil to the busbar fixed to the molded core through welding. The core component has multiple legs and a magnetic yoke connecting the legs. The coil is mounted on the foot. The bonding process includes the following steps: In the coating process, the adhesive is applied to the mating surface of the foot of the core component and the inner peripheral surface of the yoke of the core component or the molded coil opposite to the inner peripheral surface of the yoke. In the pressing process, the applied adhesive is pressed out. as well as The hardening process causes the adhesive to harden. In the pressing process, the adhesive applied to the mating surface is pressed out, thereby extruding the adhesive to at least one of the upper and lower surfaces of the foot, and extruding the adhesive to at least one of the opposite surfaces of the foot, namely the inner side of the foot and the opposite side of the inner side, namely the outer side, and adhering the adhesive to the molded coil.

2. The method for manufacturing a reactor according to claim 1, characterized in that, In the pressing process, the adhesive applied to the joint surface is pressed out and extruded to the inner side of the foot.

3. The method for manufacturing a reactor according to claim 1, characterized in that, In the pressing process, the adhesive applied to the joint surface is pressed out and extruded to the outer side of the foot.

4. The method for manufacturing a reactor according to any one of claims 1 to 3, characterized in that, The coil molding resin has a protrusion that faces the inner circumferential surface of the yoke and protrudes towards it. The protrusion has a groove. In the pressing process, the pressing is performed in such a way that the adhesive applied to the inner circumferential surface of the yoke or the molded coil opposite to the inner circumferential surface of the yoke enters the groove.

5. The method for manufacturing a reactor according to claim 4, characterized in that, The coil molding resin is composed of PPS, which refers to polyphenylene sulfide. The adhesive is composed of epoxy resin.

6. A reactor, characterized in that, have: A pair of molded cores, wherein at least a portion of the core components is covered by core molding resin; A molded coil, wherein at least a portion of the coil is covered by a coil molding resin; An adhesive that bonds the molded core to the molded coil; as well as The busbar, which is fixed to the molded core, is connected to the leads of the coil by welding. The core component has multiple legs and a magnetic yoke connecting the legs. The coil is mounted on the foot. The adhesive has the following properties: A core engagement portion, disposed between the engagement surfaces of the feet, engages the core component; An X-direction limiting portion is disposed between the inner peripheral surface of the magnetic yoke and the molded coil, thereby engaging the inner peripheral surface with the molded coil. A Y-direction limiting portion is disposed between at least one of the faces of the feet that are opposite to each other, namely the inner side of the feet and the opposite side of the inner side, namely the outer side, and the molded coil, thereby engaging the inner side or the outer side with the molded coil. as well as A Z-direction limiting portion is disposed between at least one of the upper and lower surfaces of the foot and the molded coil, thereby engaging the upper or lower surface with the molded coil.

7. The reactor according to claim 6, characterized in that, The Y-direction limiting part is disposed between the inner side of the foot and the molded coil.

8. The reactor according to claim 6, characterized in that, The Y-direction limiting part is disposed between the outer side of the foot and the molded coil.

9. The reactor according to any one of claims 6 to 8, characterized in that, The coil molding resin has a protrusion that faces the inner circumferential surface of the yoke and protrudes towards it. The protrusion has a groove. The X-direction limiting portion abuts against the protrusion and is formed inside the groove.

10. The reactor according to claim 9, characterized in that, The coil molding resin is composed of PPS, which refers to polyphenylene sulfide. The adhesive is epoxy resin.

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