Molded coil and reactor

Abstract

To provide a molded coil and a reactor in which the coil is unlikely to become misaligned in the mold and resin is formed on the coil with high precision, even without forcing the mold against the surface of the coil.SOLUTION: A molded coil 9 or a reactor 10 includes a plurality of cylindrical coils 2 arranged side by side with their cylindrical axes parallel to each other, a pair of frames 7 arranged side by side and fitted into the same surface such as the lower surface 26 of the plurality of coils 2, and a molded resin 5 covering a part or all of the coils 2 except for the inside of the frame 7. Each of the frames 7 has a protrusion extending toward the outside of the molded coil on the outer side opposite to the adjacent side facing the adjacent frame body.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a molded coil formed by molding a coil with resin, and to a reactor including the same. [Background technology]

[0002] A reactor mainly consists of a coil and a core. When electricity is passed through the coil, it generates magnetic flux according to the number of turns. The core acts as a closed magnetic circuit that allows the magnetic flux generated by the coil to pass through with a magnetic permeability higher than that of a vacuum. In other words, a reactor is an electromagnetic component that converts electrical energy into magnetic energy and stores and releases it.

[0003] Such reactors are used in a wide variety of applications, and representative examples include boost reactors, series reactors, parallel reactors, current limiting reactors, starting reactors, shunt reactors, neutral point reactors, and arc suppression reactors.

[0004] Boost reactors are incorporated into on-board boost circuits such as those used in the drive systems of hybrid and electric vehicles. Series reactors are connected in series to motor circuits to limit the current during short circuits. Parallel reactors stabilize the current sharing between parallel circuits. Current-limiting reactors limit the current during short circuits and are connected to them. Starting reactors are connected in series to motor circuits to protect the machine and limit the starting current. Shunt reactors are connected in parallel to transmission lines to compensate for leading reactive power and suppress abnormal voltages. Neutral reactors are connected between the neutral point and the ground to limit the ground fault current that flows in the event of a ground fault in the power system. Arc-suppression reactors automatically extinguish the arc that occurs when a single-line ground fault occurs in a three-phase power system.

[0005] Resin-molded reactors, in which the outer periphery of the core and coil is coated with resin to electrically insulate the coil from the core, are widely used. For example, the core is coated with a resin member, and the coil is attached to the core on top of the resin member. Furthermore, a further resin member is formed so as to cover a part or the whole of the coil attached to the core. The resin coating the coil is formed by injection molding. The coil attached to the core is placed in a mold, and resin is injected into the mold. The resin that flows around the coil solidifies, forming the resin coating the coil (see Patent Documents 1 to 3). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 5869518 [Patent Document 2] JP 2015-130410 A [Patent Document 3] JP 2018-011019 A Summary of the Invention [Problem to be solved by the invention]

[0007] Coils are made into a cylindrical shape by winding a conductive wire in a spiral shape while shifting the winding position for each turn along the winding axis. Due to manufacturing precision reasons, the coil surface has irregularities and is not necessarily smooth. Therefore, if the mold is pressed too hard against the coil surface in an attempt to bring the mold and coil into close contact with each other without any gaps, problems such as scratching the coil or damaging the coating of the coil's conductive wire can arise, resulting in a loss of insulation.

[0008] However, if the mold cannot be pressed firmly against the surface of the coil, the coil may be blown around by the injection pressure inside the mold, causing the coil to become misaligned within the mold, which may result in defects in the resin formation.

[0009] The present invention has been proposed to solve the above-mentioned problems, and its object is to provide a molded coil and a reactor in which the coil is less likely to become misaligned within the mold, and in which resin is formed on the coil with high precision, even without the mold being pressed forcefully against the surface of the coil. [Means for solving the problem]

[0010] In order to achieve the above-mentioned object, a molded coil according to an embodiment of the present invention comprises a plurality of cylindrical coils arranged side by side with their cylindrical axes parallel to one another, a plurality of frame bodies arranged side by side and fitted onto the same faces of the plurality of coils, and a molded resin covering some or all of the coils except for the inside of the frame bodies, wherein each of the frame bodies has a first protrusion portion on an adjacent edge facing the adjacent frame body, extending toward the adjacent frame body and butting against each other.

[0011] The plurality of coils may be formed by winding a single conductive wire at a plurality of spaced apart locations, and may include a connecting wire connecting the plurality of coils.

[0012] Each of the frames may have a second protrusion extending toward an outside of the reactor on an outer side opposite the adjacent side.

[0013] The frame body may have a first frame opening surface into which the coil fits and a second frame opening surface opposite the first frame opening surface, and the second protrusion portion may protrude from a height on the first frame opening surface side higher than an intermediate height between the first frame opening surface and the second frame opening surface.

[0014] The coil may have a curved surface extending along a cylindrical axis, the frame body may have a pair of vertical side portions extending along the cylindrical axis of the coil and in close contact with the curved surface of the coil, and the second protrusion portion may protrude from a position of the vertical side portions that is in close contact with the curved surface of the coil.

[0015] The second protrusion portions may protrude at intervals along the outer edge, and the molded resin may have a frame support portion extending from between the second protrusion portions to at least the surface of the second protrusion portion facing away from the coil.

[0016] The first protrusion portions may protrude at intervals along the adjacent sides, and the molding resin may have a frame support portion extending from between the first protrusion portions to at least the surface of the first protrusion portion facing away from the coil.

[0017] The frame body may have a third protrusion extending from an edge perpendicular to the adjacent edge, and the molding resin may have a frame support portion extending on at least a surface of the third protrusion facing away from the coil.

[0018] A reactor including this molded coil and a core including a magnetic body to which the coil is attached is also one aspect of the present invention. Effect of the Invention

[0019] According to the present invention, the frame bodies abut against each other within the mold and become immobile, and the coil fitted in the frame body also becomes immobile, so that the coil is less likely to become displaced even by the injection pressure of the resin. [Brief description of the drawings]

[0020] [Figure 1] FIG. 2 is a perspective view of the reactor, showing the reactor without the members covering each portion. [Diagram 2] FIG. 2 is a perspective view showing a core coating resin that coats the core. [Diagram 3] FIG. 2 is a top perspective view showing a reactor. [Figure 4] FIG. 2 is a bottom perspective view showing the reactor. [Diagram 5] FIG. [Figure 6] FIG. 2 is a cross-sectional perspective view showing the frame body taken along line AA. [Figure 7] FIG. 2 is a bottom perspective view showing the reactor housed in the mold. [Figure 8] FIG. 2 is a front view showing the reactor housed in the mold. [Figure 9] FIG. 4 is a cross-sectional view showing an inflow state of resin. [Figure 10] FIG. 4 is a bottom perspective view showing a frame supported by molded resin. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Hereinafter, a molded coil and a reactor according to an embodiment of the present invention will be described with reference to the drawings. In each drawing, thickness, dimensions, positional relationship, ratio, shape, and the like may be emphasized for ease of understanding, but the present invention is not limited to such emphasis.

[0022] FIG. 1 is a perspective view showing the main configuration of the reactor of this embodiment, and for convenience of explanation, the members covering each part are omitted. The reactor 10 includes one annular core 1 and two coils 2, 2. The two coils 2, 2 are fitted side by side in one core 1. The coils 2, 2 generate magnetic flux according to the number of turns when current is applied. The core 1 becomes a closed magnetic circuit that passes the magnetic flux generated by the coils 2, 2 with a magnetic permeability higher than that of a vacuum. In other words, the reactor 10 is an electromagnetic component that converts electric energy into magnetic energy and stores and releases it.

[0023] The core 1 includes a magnetic body such as a dust core, a ferrite core, a metal composite core, or a laminated steel plate. The dust core is a powder compact obtained by compressing magnetic powder and annealing it. The magnetic powder is mainly composed of iron, and examples of the magnetic powder include pure iron powder, permalloy (Fe-Ni alloy) mainly composed of iron, Si-containing iron alloy (Fe-Si alloy), sendust alloy (Fe-Si-Al alloy), amorphous alloy, nanocrystalline alloy powder, and a mixture of two or more of these powders. The metal composite core is a core formed by kneading magnetic powder and resin and molding them.

[0024] The two coils 2,2 are formed as a linked coil 29 made by winding two separate points of a single conductive wire 23, such as a copper wire, separately without separating them. Each coil 2 is formed by winding the conductive wire 23 in a spiral shape while shifting the winding position for each turn along the winding axis. The two coils 2,2 are arranged side by side with their axes parallel to each other and with the currents flowing through the two coils 2,2 in opposite directions. When the two coils 2 are arranged side by side, the winding directions of the two coils 2,2 are the same.

[0025] The wire in one conductive wire 23 at the end closer to the coils 2, 2 is drawn out from the first end surface 21 of each coil 2. The conductive wire 23 drawn out from the first end surface 21 is connected to an electric circuit, allowing current to flow through the coils 2. In addition, the wire between the coils 2, 2 in one conductive wire 23 forms a connecting wire 24 that connects the two coils 2, 2, and is drawn out from the second end surface 22 of one coil 2 and introduced into the second end surface 22 of the other coil 2.

[0026] The coil 2 has an outer shape formed by alternately connecting four curved surfaces and four flat surfaces that are perpendicular to the first end face 21 and the second end face 22 and parallel to the cylindrical axis. That is, the coil 2 has an upper surface 25 that is a flat surface parallel to the surface on which the annular shape of the core 1 appears, and also has a flat lower surface 26 on the opposite side to the upper surface 25. The coil 2 has a side surface 27 that is a flat surface perpendicular to the upper surface 25 and the lower surface 26. The coil 2 has a lower curved surface 28 between the lower surface 26 and the side surface 27.

[0027] The flat surface of coil 2 refers to a surface that is flat in relative comparison with a curved surface, and also includes a surface that forms a large arc with a gentle curvature due to the swelling of the conductive wire. The top and bottom refer to the upper and lower dies that house reactor 10 when covering reactor 10 by molding, and do not refer to the positional relationship or direction when reactor 10 is mounted on the actual device to be installed.

[0028] Hereinafter, in the reactor 10, the up-down direction refers to the Z-axis direction perpendicular to the upper surface 25 and the lower surface 26. The direction from the lower surface 26 toward the upper surface 25 is referred to as the upper side, and the direction from the upper surface 25 toward the lower surface 26 is referred to as the lower side. The horizontal direction refers to the Y-axis direction parallel to the lower surface 26 of the coil 2 and perpendicular to the side surface 27 of the coil 2. Within the horizontal direction, the direction approaching the reactor axis 11 drawn at a position equidistant from the two coils 2 is referred to as the inner side, and the direction away from the reactor axis 11 is referred to as the outer side. The vertical direction refers to the X-axis direction perpendicular to the horizontal direction, parallel to the lower surface 26, along the cylinder axis, and parallel to the side surface 27.

[0029] As shown in Figures 2 to 4, this reactor 10 includes a core coating resin 3, a plate body 6, a frame body 7, and a molded resin 5 that coat the various components. The core coating resin 3, the plate body 6, the frame body 7, and the molded resin 5 are molded products that retain a certain shape and have insulating properties and heat resistance. The core coating resin 3, the plate body 6, the frame body 7, and the molded resin 5 may be made of the same type of material, or may be made of different materials. A thermally conductive filler may be mixed into the core coating resin 3, the plate body 6, the frame body 7, and the molded resin 5.

[0030] For example, the core coating resin 3, the plate body 6, the frame body 7 and the molding resin 5 are made of materials such as epoxy resin, unsaturated polyester resin, urethane resin, BMC (Bulk Molding Compound), PPS (Polyphenylene Sulfide), PBT (Polybutylene Terephthalate), or a composite of these.

[0031] Fig. 2 is a perspective view showing the core coating resin 3. As shown in Fig. 2, the core coating resin 3 coats the core 1. The core coating resin 3 may cover the entire periphery of the core 1, or a part of the surface of the core 1 may be exposed from the viewpoint of heat dissipation and the like. The coil 2 is fitted into the core 1 from above the core coating resin 3, and the coil 2 and the core 1 are electrically insulated by the core coating resin 3.

[0032] Fig. 3 is a top perspective view of reactor 10 in which plate body 6, frame body 7, and molded resin 5 are formed, and Fig. 4 is a bottom perspective view of reactor 10. As shown in Fig. 3, one plate body 6 is disposed on top surface 25 of each coil 2, covering top surface 25. As shown in Fig. 4, one frame body 7 is disposed on bottom surface 26, which is the same surface of each coil 2. Since two coils 2 are arranged side by side with their cylindrical axes parallel, a pair of frame bodies 7 are arranged next to each other.

[0033] This plate body 6 is a buffer material interposed between the upper surface 25 of the coil 2 and the die so that the upper surface 25 of the coil 2 is not damaged by the die when molding the molded resin 5. The coil 2 is pressed by the die through the plate body 6, and is supported so as to suppress misalignment within the die, and the plate body 6 is pressed against it to correct any unevenness or twists on the surface. Therefore, the plate body 6 only needs to have an area that ensures a strength sufficient to prevent damage even when pressed by the die, and may be open on the inside, with part of the upper surface 25 of the coil 2 exposed from the viewpoint of heat dissipation.

[0034] Furthermore, the frame 7 is a buffer material interposed between the lower surface 26 of the coil 2 and the mold so that the lower surface 26 is not damaged by the mold. The coil 2 is pressed by the mold via the frame 7, and is supported so as to suppress misalignment within the mold, and the frame 7 is pressed against the coil 2 to correct surface irregularities and twists. Each frame 7 further includes the entire width range of the lower surface 26 of each coil 2 within the frame, and serves as a barrier to prevent the molded resin 5 from flowing into the frame, exposing the coil 2 from the molded resin 5 and improving the heat dissipation of the coil 2.

[0035] As shown in FIG. 3 and FIG. 4, the molded resin 5 is formed by placing the plate body 6, the frame body 7, and the coil 2 in a mold, injecting the molded resin 5 into the mold, and solidifying it. The molded resin 5 covers the coil 2 together with the plate body 6 and the frame body 7, except for the inside of the frame body 7. That is, the reactor 10 incorporates a molded coil 9 including the coil 2 and the molded resin 5 that covers the coil 2. The molded coil 9 refers to an integrated product of the coil 2 and the molded resin 5 that covers the coil 2, and the molded resin 5 may additionally cover other members. The molded resin 5 covers the coil 2 including the connecting wire 24, except for the drawn conductive wire 23. In this embodiment, the molded resin 5 further covers the core covering resin 3, and the molded coil 9 is also integrated with the core 1.

[0036] Additionally, a sensor 4 is provided in the reactor 10. The sensor 4 is, for example, a thermistor that detects temperature. The sensor 4 is inserted between the two coils 2, 2. In this embodiment, the molded resin 5 further covers the sensor 4, and the molded coil 9 may integrate the coil 2, the core 1, and the sensor 4.

[0037] The frame 7 will be described in more detail. FIG. 5 is a perspective view showing a detailed configuration of the frame 7. FIG. 6 is a perspective view of the AA cross section of FIG. 5. As shown in FIG. 5, the frame bodies 7 installed on the coils 2 are of the same shape and size and are of the same congruent shape. The frame body 7 has a pair of horizontal side portions 71 and a pair of vertical side portions 72, and is a roughly rectangular frame defined by the vertical side portions 72 and the horizontal side portions 71. The frame body 7 is installed on the coil 2 so that the coil 2 is fitted into a first frame opening surface 731, which is one opening surface of the frame body 7. When the coil 2 is fitted into the frame body 7, the surface of the coil 2 is exposed through a second frame opening surface 732 opposite to the first frame opening surface 731.

[0038] The pair of vertical side portions 72 are spaced apart across the lower surface 26 of the coil 2, and extend parallel to the cylindrical axis of the coil 2. Therefore, one vertical side portion 72 is an adjacent side 81 facing the adjacent frame body 7, and the other vertical side portion 72 facing the adjacent side 81 is an outer side 82 located on the lateral outside of the reactor 10. These vertical side portions 72 have the same length as the length of the coil 2 in the cylindrical axis direction. These vertical side portions 72 are in close contact with the lower curved surface 28 of the coil 2.

[0039] Moreover, one horizontal side portion 71 extends in close contact with the first end surface 21 of the coil 2, completely traversing the first end surface 21. The other horizontal side portion 71 extends in close contact with the second end surface 22 of the coil 2, completely traversing the second end surface 22. In other words, the lower surface 26 of the coil 2 is exposed from the frame 7. The frame 7 has a height such that when the vertical side portion 72 is in close contact with the lower curved surface 28 of the coil 2, it extends below the lower surface 26.

[0040] The frame 7 has a first protrusion 76 on an adjacent side 81 of the vertical side portion 72. A plurality of first protrusions 76 protrude along the adjacent side 81 with gaps 78 provided therebetween. For example, the first protrusions 76 protrude from both ends and the center of the adjacent side 81. Each first protrusion 76 protrudes parallel to the lateral direction of the reactor 10, and the end faces form vertical cliffs that extend parallel to the vertical direction and the longitudinal direction. Furthermore, each first protrusion 76 has the same protrusion height, protrusion length, protrusion width and thickness relative to the frame 7.

[0041] Moreover, the frame 7 is provided with a second protrusion 77 on an outer side 82 of the vertical side portion 72. A plurality of second protrusions 77 protrude along the outer side 82 with gaps 78 provided therebetween. For example, the second protrusions 77 protrude from both ends and the center of the outer side 82. Each second protrusion 77 protrudes parallel to the lateral direction of the reactor 10, and the end faces form vertical cliffs that extend parallel to the vertical direction and the longitudinal direction. Each second protrusion 77 has the same protrusion height, protrusion length, protrusion width, and thickness relative to the frame 7.

[0042] Furthermore, the frame body 7 is provided with a third protrusion 79. The third protrusion 79 protrudes from both horizontal sides 71. The third protrusion 79 extends continuously along the horizontal sides 71. The first protrusion 76, the second protrusion 77, and the third protrusion 79 protrude from the same height of the frame body 7, and protrude from a height on the first frame opening surface 731 side, which is higher than the intermediate height between the first frame opening surface 731 and the second frame opening surface 732 of the frame body 7.

[0043] As shown in Fig. 6, the vertical side portion 72 has a vertical portion 74 and a curved portion 75. The curved portion 75 and the vertical portion 74 are seamlessly connected, and the vertical portion 74 extends from the lower end of the curved portion 75 and extends perpendicular to the plane in which the lower surface 26 of the coil 2 extends. The vertical portion 74 surrounds the periphery of the second frame opening surface 732 of the frame body 7, and the curved portion 75 is in close contact with the coil 2 at its curved inner peripheral surface. The curved portion 75 is defined by a contact surface 751, an upper end surface 753, and an outer surface 752, except for the connection area with the vertical portion 74 and the connection area with the horizontal side portion 71.

[0044] That is, when going around the vertical side portion 72, it starts from the contact surface 751, then from the contact surface 751 to the upper end surface 753, then from the upper end surface 753 via the first protrusion portion 76 or the second protrusion portion 77 to the outer surface 752, then from the outer surface 752 to the vertical portion 74, and finally from the vertical portion 74 back to the contact surface 751.

[0045] The contact surface 751 is an inner peripheral surface of the frame 7, and curves to coincide with a partial arc range of the lower curved surface 28 of the coil 2. The frame 7 comes into contact with the lower curved surface 28 at the contact surface 751. The upper end surface 753 is an upper end surface adjacent to the contact surface 751. The upper end surface 753 is adjacent to the contact surface 751, and expands in a direction away from the lower curved surface 28.

[0046] The outer surface 752 is adjacent to the upper end surface 753 and constitutes the outer peripheral surface of the frame body 7. This outer surface 752 is the opposite surface to the contact surface 751, and is curved or inclined due to the influence of the curved shape of the contact surface 751. The first protrusion 76 and the second protrusion 77 protrude from this curved outer surface 752. For example, the first protrusion 76 and the second protrusion 77 protrude from a height that is flush with the upper end surface 753. Therefore, the outermost lateral surface of the frame body 7 is vertical due to the cliffs of the first protrusion 76 and the second protrusion 77.

[0047] 7 is a bottom perspective view showing the reactor 10 housed in a mold. As shown in FIG. 7, such a frame 7 is fitted into each coil 2, the lateral outer side abuts against the mold, and the first protrusions 76 are pressed against each other on the adjacent side 81 side. Therefore, the frame 7 is immovable in the lateral direction within the mold. Even if the coil 2 is blown by the injection pressure of the molded resin 5, it is unlikely to become displaced within the mold because it is fitted into the first frame opening surface 731 of the frame 7, which is immovable. Therefore, the molded resin 5 can cover the coil 2 with high precision.

[0048] In particular, when the two coils 2, 2 are linked coils 29, there is a manufacturing variability in the distance between the two coils 2, 2 and in the parallelism between the two coils 2, 2. However, the frame 7 is separate for each coil 2. Therefore, each coil 2 fits into the frame 7 with high precision, making it difficult for the coils 2 to come off the frame 7 due to the injection pressure in the mold.

[0049] Moreover, because the first protrusions 76 of the frame 7 are pressed against each other, the frame 7 is positioned with high precision, and the distance between and parallelism between the coils 2 mounted on the frame 7 are also corrected. Therefore, even if the coils 2 are linked coils 29, the coils 2 are positioned with high precision within the mold and are coated with high precision.

[0050] Fig. 8 is a front view showing the reactor 10 accommodated in a mold. As shown in Fig. 8, the mold has a lower mold K1, a frame body 7 is placed on the lower mold K1, a coil 2 is fitted into the frame body 7, a plate body 6 is placed on the coil 2, and an upper mold K2 is placed on the plate body 6. This lower mold K1 has side parts K12 that support the frame body 7 from the lateral direction. Therefore, the pair of frame bodies 7 are pressed against each other by the first protrusion parts 76, and both ends are sandwiched between the side parts K12, so that the pair of frame bodies 7 are more stable in the mold, the coil 2 is more unlikely to be displaced in the mold, and the molding resin 5 covers the coil 2 with more precision.

[0051] Moreover, the second protrusion 77 protrudes from the position of the curved portion 75 of the vertical side portion 72, which is roughly divided into a vertical portion 74 and a curved portion 75. That is, it protrudes from a position higher on the first frame opening surface 731 side than the intermediate position between the first frame opening surface 731 and the second frame opening surface 732. Since the frame body 7 and the side portion K12 of the lower mold K1 are supported by the second protrusion 77 protruding from this higher position, the frame body 7 is further stabilized within the mold.

[0052] In addition, since the side portion K12 of the lower mold K1 abuts against the second protrusion 77, it is not affected by the curved or bent outer surface 752 of the frame 7, and stands vertically following the cliff of the second protrusion 77. The vertically standing side portion K12 can be produced inexpensively and with high dimensional accuracy compared to the case where it is bent or curved following the outer surface 752 of the frame 7. Therefore, the production cost of the reactor 10 is also reduced.

[0053] In this manner, the frame 7 is stabilized in the mold, and the molding resin 5 is injected into the mold while the coil 2 fitted in the first frame opening surface 731 of the frame 7 is fixed in position. Here, the gate for injecting the molding resin 5 is located closer to the upper die K2 than the first frame opening surface 731 of the frame 7, but since gaps 78 are provided between the first protrusions 76 and between the second protrusions 77, the molding resin 5 also flows under the first protrusions 76 and the second protrusions 77 through the gaps 78, as shown in FIG. 9. The molding resin 5 also flows around the third protrusion 79 and under the third protrusion 79.

[0054] 10, a frame support portion 51 is created in the molded resin 5, which passes between the multiple first protrusions 76, envelops the first protrusions 76 so as to support the lower surfaces of the first protrusions 76, and supports the frame body 7 from the adjacent side 81. Also, a frame support portion 51 is created in the molded resin 5, which passes between the multiple second protrusions 77, envelops the second protrusions 77 so as to support the lower surfaces of the second protrusions 77, and supports the frame body 7 from the outer side 82.

[0055] Furthermore, in the molded resin 5, frame support parts 51 are created that wrap around the third protrusion 79 to support the lower surface of the third protrusion 79 and support the frame body 7 from both horizontal side parts 71. Here, the molded resin 5 supports the frame body 7 so as not to fall by being in close contact with the upper surfaces of the horizontal side parts 71 and vertical side parts 72 of the frame body 7, and further supports the frame body 7 so as not to fall by entering the gaps 78 between the first protrusions 76 or the second protrusions 77. However, these frame support parts 51 further reliably prevent the frame body 7 from coming off the reactor 10 after the molded resin 5 has hardened.

[0056] As described above, the molded coil 9 or reactor 10 includes a plurality of cylindrical coils 2 arranged side by side with their cylindrical axes parallel to each other, a pair of frame bodies 7 arranged side by side and fitted into the same surface such as the lower surface 26 of the plurality of coils 2, and molded resin 5 covering a part or all of the coils 2 except for the inside of the frame body 7. Each of the frame bodies 7 has a first protrusion 76 on an adjacent side 81 facing the adjacent frame body 7, which extends toward the adjacent frame body 7 and butts against each other.

[0057] As a result, the first protrusions 76 of the frames 7 are pressed against each other on the adjacent sides 81, and the frames 7 are immovable in the lateral direction within the mold. The coil 2 is also fitted into the frame 7, which is immovable, and is therefore unlikely to become displaced within the mold even if it is subjected to the injection pressure of the molding resin 5. Therefore, the coil 2 can be covered with the molding resin 5 with high precision.

[0058] The coils 2 are formed by winding a single conductive wire 23 at multiple separated locations, and have connecting wires 24 connecting the coils 2. That is, the connected coils 29 have first protrusions 76, and separate frames 7 are prepared for each coil 2.

[0059] As a result, even if the coils are linked coils 29, each coil 2 fits precisely into the frame 7, and is unlikely to come off from the frame 7 due to the injection pressure in the mold. Furthermore, because the first protrusions 76 of the frame 7 are pressed against each other, the frame 7 is positioned precisely, and the spacing and parallelism of the coils 2 placed on the frame 7 are also corrected.

[0060] In addition, each of the frames 7 has a second protrusion 77 extending toward the outside of the reactor 10 on the outer side 82 facing the adjacent side 81. As a result, even if the frame 7 has a pair of vertical side portions 72 that are in close contact with the lower curved surface 28 of the coil 2, the side portions K12 of the lower die K1 can be formed in a vertically rising shape, and the lower die K1 can be inexpensive and has high dimensional accuracy. As a result, the production cost of the reactor 10 can be reduced.

[0061] Further, the frame body 7 has a first frame opening surface 731 into which the coil 2 fits, and a second frame opening surface 732 opposite to the first frame opening surface 731, and the second protrusion 77 protrudes from a height on the first frame opening surface 731 side higher than the height between the first frame opening surface 731 and the second frame opening surface 732. This allows the lower mold K1 to support the sides of the frame body 7 at a high position, improving the stability of the frame body 7 within the mold. Therefore, even if the coil 2 is blown by the injection pressure of the molding resin 5, it is more difficult for the position to shift within the mold.

[0062] Furthermore, by having a plurality of second protrusions 77 protrude at intervals along outer side 82, molded resin 5 has frame support parts 51 extending from between second protrusions 77 to at least the undersides of second protrusions 77 facing away from coil 2. This allows frame body 7 to be supported by molded resin 5 from the outer side 82 side, and prevents frame body 7 from falling off reactor 10.

[0063] Furthermore, by having a plurality of first protrusions 76 protrude at intervals along adjacent side 81, molded resin 5 has frame support parts 51 extending from between first protrusions 76 to at least the undersides of first protrusions 76 facing away from coil 2. This allows frame body 7 to be supported by molded resin 5 from the adjacent side 81 side, preventing frame body 7 from falling off reactor 10.

[0064] Furthermore, by providing third protrusion 79 extending from an edge of frame 7 perpendicular to outer edge 82 and adjacent edge 81, i.e., horizontal edge 71, molded resin 5 has frame support portion 51 extending from at least the lower surface of third protrusion 79 facing away from coil 2. This allows frame 7 to be supported by molded resin 5 from the horizontal edge 71 side, preventing frame 7 from falling off reactor 10.

[0065] The above-mentioned embodiment of the present invention is presented as an example, and the present invention is not limited to the above-mentioned embodiment. The above-mentioned embodiment can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the scope of the invention. The embodiment and its modifications are included in the scope of the present invention.

[0066] In this embodiment, the molded resin 5 constituting the molded coil 9 covers not only the coil 2, but also the core 1 covered with the core covering resin 3 and the sensor 4. However, the present invention is not limited to this, and the molded coil 9 may cover only the coil 2.

[0067] In this case, the reactor 10 may be produced by mounting the molded coil 9 on the core 1 coated with the core coating resin 3, attaching the sensor 4, housing these in a mold and further coating them from the outside with resin, and integrating the molded coil 9, core coating resin 3, core 1 and sensor 4 with further resin to produce the reactor 10. Alternatively, the reactor 10 may be produced by mounting the molded coil 9 on the core 1 not coated with the core coating resin 3, attaching the sensor 4, housing these in a mold and further coating them from the outside with resin, and integrating the molded coil 9, core 1 without the core coating resin 3 and sensor 4.

[0068] Even in the molded coil 9 incorporated into such a reactor 10, by having a frame body having a first protrusion 76, a second protrusion 77, a third protrusion 79, or a combination of these, the frame body 7 abuts against each other within the mold and becomes immobile, and the coil 2 fitted into the frame body 7 also becomes immobile, making it less likely that the coil 2 will become misaligned even due to the injection pressure of the resin.

[0069] The frame 7 is not limited to being a single part in which a pair of horizontal sides 71 and a pair of vertical sides 72 are seamlessly connected, but may be formed by combining a plurality of parts. For example, the frame 7 may be formed by combining a U-shaped frame part in which a horizontal side 71 on one side is seamlessly connected to vertical sides 72 on both sides, and a linear frame part formed by the horizontal side 71 on one side to define a substantially rectangular shape.

[0070] For example, the width of the gap between the pair of vertical side portions 72 and the length of the linear frame part are made to match, and the linear frame part is fitted into the U-shaped part to form the frame body 7. With this structure, the linear frame part can be slid along the vertical side portions 72. Then, even if the coil 2 is compressed so that the winding axis direction is shortened by the injection pressure of the molded resin 5 and the vertical length of the lower surface 26 fluctuates, the linear part slides to form the frame body 7 that matches the lower surface 26. This frame body 7 continues to surround the lower surface 26 without any gaps. Therefore, it is possible to prevent the molded resin 5 from entering the lower surface 26 side while exposing the lower surface 26 over the entire vertical direction.

[0071] The plate body 6 may be omitted as a member covering the coil 2. In this case, the upper die K2 may be pressed directly against the upper surface 25 of the coil 2. For example, since the lower surface 26 of the coil 2 is brought into contact with a metal cooling plate or the like via a heat dissipation sheet, scratches on the lower surface 26 of the coil 2 may cause insulation failure. On the other hand, in cases where no metal member or the like is disposed near the upper surface 25 of the coil 2 and it is not necessary to take measures to prevent scratches on the upper surface 25 of the coil 2 as with the lower surface 26, the plate body 6 is not essential.

[0072] Furthermore, if the frame bodies 7 can press the first protrusion portions 76 against each other on the adjacent side 81 side, the frame body 7 will not move in its lateral direction within the mold even if the outer edge 82 opposite the adjacent side 81 is directly supported by the side portion K12 of the lower mold K1.

[0073] Even if the reactor 10 is provided with two coils 2, 2 fabricated separately instead of the linked coil 29, as long as the frame 7 is provided, positional deviation is suppressed even when the coils are stirred by the injection pressure of the molding resin 5. [Explanation of symbols]

[0074] 1 core 2 Coil 21 First end surface 22 Second end face 23 Conductive Wire 24 Connecting Lines 25 Top 26 Bottom side 27 Side 28 Lower curved surface 29 Connected coil 3 Core coating resin 4 Sensors 5. Mold Resin 51 Frame support part 6 Plate 7 Frame 71 Side part 72 Vertical side 731 First frame opening surface 732 Second frame opening surface 74 Vertical section 75 Curved section 751 Contact surface 752 Exterior 753 Upper end face 76 1st protrusion 77 Second protrusion 78 void 79 Third protrusion 81 Adjacent Side 82 Outer Edge 9 Molded coil 10 Reactor 11 Reactor shaft K1 lower mold K12 Lateral part K2 upper mold

Claims

1. A molded coil having a plurality of cylindrical coils arranged side by side with their cylindrical axes parallel to each other, A plurality of frame bodies arranged side by side and fitted to the same surfaces of the plurality of coils; a molding resin that covers a part or all of the coil except for the inside of the frame of the frame body; Equipped with each of the frames has a protrusion extending toward the outside of the molded coil on an outer side opposite to an adjacent side facing the adjacent frame; A molded coil characterized by:

2. the plurality of coils are formed by winding a single conductive wire at a plurality of spaced apart locations, and a connecting wire is provided to connect the plurality of coils; 2. The molded coil according to claim 1,

3. The frame body is a first frame opening surface into which the coil is fitted; a second frame opening surface opposite to the first frame opening surface; having the protrusion protrudes from a height on the first frame opening surface side higher than an intermediate height between the first frame opening surface and the second frame opening surface; 2. The molded coil according to claim 1,

4. The coil has a curved surface extending along a cylindrical axis, the frame body has a pair of vertical side portions that extend along a cylindrical axis of the coil and are in close contact with the curved surface of the coil, the protrusion protrudes from a position of the vertical side portion that is in close contact with the curved surface of the coil; 4. The molded coil according to claim 1 or 3, characterized in that

5. The protrusions protrude at intervals along the outer side, the molding resin has a frame support portion extending from between the second protrusions to at least a surface of the protrusion facing away from the coil; 5. The molded coil according to claim 1, 3 or 4, characterized in that

6. a second protrusion extending from a side of the frame perpendicular to the adjacent side, the molding resin has a frame support portion extending on at least a surface of the other protrusion portion facing away from the coil; 7. The molded coil according to claim 1, wherein:

7. A molded coil according to any one of claims 1 to 6, a core including a magnetic body on which the coil is mounted; To have A reactor characterized by the above.

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