Molded coils and reactors

Abstract

To provide a mold coil with which the positional accuracy of a lead line from the coil is good, and that can be easily installed to a reactor with high accuracy, and the reactor that can be easily installed to a circuit with high accuracy.SOLUTION: The present invention comprises a cylindrical coil 3b which is a wound body of a conductive wire, a lead line 4b that is extracted from an end face of the coil 3b, and a coil covering resin 6 that covers the whole or a part of the coil 3b, and is interposed between a core 2 and the coil 3b. The coil covering resin 6 has a plate body 71, a line plate 72a, a connecting plate 73a and a mold resin 10. The plate body 71 covers a partial region on a circumferential surface of the coil 3b, the line plate 72a covers a part of the lead line 4b, the connecting plate 73a connects the plate body 71 and the line plate 72a, and the mold resin 10 covers the whole or a part of a surface of the coil 3b, except the region covered by the plate body 71 and the line plate 72. The connecting plate 73a is made to have lower rigidity than the plate body 71 and the line plate 72a.SELECTED DRAWING: Figure 4

Description

[Technical Field]

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

[0002] A reactor mainly consists of a coil and a core. When current is passed through the coil, it generates magnetic flux according to the number of turns. Hereinafter, the coil that functions as an inductive reactance by generating magnetic flux when current is passed through it from the outside is called the main coil. The core is a closed magnetic circuit that passes the magnetic flux generated by the coil with a magnetic permeability higher than that of a vacuum. This 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, including boost reactors, series reactors, parallel reactors, current limiting reactors, starting reactors, shunt reactors, neutral reactors, and arc suppression reactors.

[0004] Boost reactors are incorporated into onboard boost circuits such as those found in the drive systems of hybrid and electric vehicles. Series reactors are connected in series to motor circuits to limit current during short circuits. Parallel reactors stabilize current sharing between parallel circuits. Current-limiting reactors limit current during short circuits and are connected to them. Starting reactors are connected in series to motor circuits to protect the machine and limit 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-phase ground fault occurs in a three-phase power system.

[0005] Reactors sometimes use molded coils, where the outer circumference of the coil is covered with resin. However, the coil is made into a cylindrical shape by spirally winding conductive wire along the winding axis, with the winding position shifted for each turn. Due to manufacturing precision reasons, the coil surface has irregularities and is not necessarily smooth.

[0006] Therefore, when molding the resin, the mold is pressed firmly against the surface of the coil to correct any twists or irregularities on the coil surface. However, pressing the mold firmly against the coil surface can damage the coil or break the coating on the coil's conductive wire, resulting in a loss of insulation. Therefore, a plate is placed on the coil in advance, and the mold is pressed against the coil via the plate to eliminate any irregularities or twists on the coil surface.

[0007] Furthermore, a lead wire is drawn from the coil to introduce current into the coil. This lead wire also needs to be held down by the mold to prevent it from being blown around inside the mold when the resin is molded. If the lead wire is also held down directly by the mold, it may be scratched or the conductive wire coating may be damaged, resulting in a loss of insulation. Therefore, a cover is placed on the lead wire, and the lead wire is held down by the mold via the cover. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Patent Publication No. 2021-122964 [Patent Document 1] Patent Publication No. 2021-61346 Summary of the Invention [Problem to be solved by the invention]

[0009] When resin is molded onto the coil, a plate is placed on the surface of the coil to cover the lead wires. The plate and cover are sometimes molded together in a single mold to reduce costs. When the plate and cover are molded together, the cover moves in conjunction with the displacement of the plate to eliminate unevenness and twists on the coil surface.

[0010] As a result, the integrally molded product of the plate and cover is positioned at an angle within the mold. For example, if the plate is lowered too much, the cover will rise, and if the plate is raised too much, the cover will sink. If the position of the lead wire cover changes in conjunction with the plate, the lead wire may be twisted by the force of the cover or may be blown away without being held down by the mold.

[0011] That is, the lead wires may be twisted or tilted, resulting in a deterioration in positional accuracy. If the positional accuracy of the lead wires is reduced, it becomes difficult to install the bus bar to be welded to the lead wires on the terminal block, making it difficult to easily and accurately install the molded coil on the reactor. Furthermore, the terminal block may become distorted, making it difficult to easily and accurately install the reactor on the circuit.

[0012] The present invention has been proposed to solve the above-mentioned problems, and its object is to provide a molded coil in which the positional accuracy of the lead wires from the coil is good and which can be easily and accurately installed in a reactor, and a reactor that can be easily and accurately installed in a circuit. [Means for solving the problem]

[0013] In order to achieve the above-mentioned object, a molded coil according to an embodiment of the present invention comprises a cylindrical coil which is a wound body of conductive wire, a lead wire drawn out from the end face of the coil, and a coil coating resin which covers part or all of the coil, wherein the coil coating resin has a plate body which covers a portion of the circumferential surface of the coil, a wire plate which covers part of the lead wire, a connecting plate which connects the plate body and the wire plate, and a molded resin which covers all or part of the surface of the coil except for the area covered by the plate body and the wire plate, and the connecting plate has lower rigidity than the plate body and the wire plate.

[0014] The plate body and the linear plate may be made of a plate that is relatively thicker than the connecting plate, and the connecting plate may be made of a plate that is relatively thinner than the plate body and the linear plate.

[0015] The coil coating resin may be thinner than the plate body and the linear plate and have an embedded portion embedded in the molded resin around part or the entire circumference of the plate body and the linear plate, and the connecting plate may be connected to the plate body via the embedded portion.

[0016] The connecting plate may have a surface narrower than the buried portion and extend between the plate body and the linear plate.

[0017] The connecting plate may have a side surface portion extending from the connecting plate in a thickness direction thereof and covering the lead wire together with the connecting plate, the side surface portion being shorter than the wide surface of the lead wire.

[0018] The plate may have a mold contact surface that comes into contact with a mold when the molding resin is formed.

[0019] The lead wire may be drawn out in a direction perpendicular or oblique to the cylindrical axis of the coil.

[0020] The lead wire may be drawn out in a direction perpendicular or oblique to the cylindrical axis of the coil, and may be further bent in a direction along the cylindrical axis of the coil.

[0021] In order to achieve the above object, a reactor according to an embodiment of the present invention includes any one of these molded coils and a core including a magnetic body and on which the molded coil is attached. [Effects of the Invention]

[0022] According to the present invention, a molded coil in which the lead wires from the coil have good positional accuracy and can be easily and accurately installed in a reactor, and a reactor in which the molded coil can be easily and accurately installed in a circuit can be obtained. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 2 is a perspective view showing the main configuration of a reactor. [Figure 2] FIG. 2 is a perspective view showing a molded coil. [Figure 3] FIG. 10 is a perspective view showing a molded coil from which molding resin is omitted. [Figure 4] FIG. [Figure 5] FIG. 10 is a perspective view showing a coil with an upper spacer installed; [Figure 6] FIG. 2 is a schematic diagram showing a cross section of a molded coil. [Figure 7] FIG. 10 is a schematic diagram showing an upper spacer when the coil is wound with high precision. [Figure 8] FIG. 10 is a schematic diagram showing an upper spacer when the coil is wound so as to have a small diameter overall. [Figure 9] FIG. 10 is a schematic diagram showing an upper spacer when the coil is wound so as to have a small diameter overall. DETAILED DESCRIPTION OF THE INVENTION

[0024] Hereinafter, reactors according to embodiments of the present invention will be described with reference to the drawings. In the drawings, thicknesses, dimensions, positional relationships, ratios, shapes, and the like may be emphasized for ease of understanding, but the present invention is not limited to such emphasis.

[0025] FIG. 1 is a perspective view showing the main configuration of a reactor 1 according to this embodiment. For ease of explanation, the illustration does not include the materials that cover each part. The reactor 1 includes one annular core 2 and two coils 3a and 3b. The two coils 3a and 3b are attached to the core 2. The coils 3a and 3b are inductors that generate magnetic flux according to the number of turns when current is passed through the circuit in which the reactor 1 is incorporated, and introduce inductive reactance into the circuit. The core 2 forms a closed magnetic circuit that passes the magnetic flux generated by the coils 3a and 3b with a magnetic permeability higher than that of a vacuum. In other words, the reactor 1 is an electromagnetic component that converts electrical energy into magnetic energy and stores and releases it.

[0026] The core 2 contains a magnetic material such as a powder magnetic core, a ferrite magnetic core, a metal composite core, or a laminated steel plate. A powder magnetic core is an annealed compact made by compressing magnetic powder. The magnetic powder is primarily composed of iron, and examples thereof include pure iron powder, iron-based permalloy (Fe-Ni alloy), Si-containing iron alloy (Fe-Si alloy), sendust alloy (Fe-Si-Al alloy), and a mixture of two or more of these powders. The magnetic powder may be an amorphous alloy or a nanocrystalline alloy powder. A metal composite core is a core made by kneading and molding magnetic powder and resin.

[0027] The magnetic material may be distributed continuously in a circular pattern in the core 2. A magnetic gap to prevent a decrease in inductance may be provided midway through the core 2. The magnetic gap may be made of a non-magnetic material, ceramic, non-metal, resin, carbon fiber, or a composite material of two or more of these, gap paper, or an air gap.

[0028] Both coils 3a and 3b are cylindrically wound conductive wires with an insulating coating such as enamel, and are formed by winding the wires in a spiral shape while shifting the winding position for each turn along the winding axis. The conductive wires of coils 3a and 3b are, for example, rectangular wires, and are spiral edgewise coils formed by winding the conductive wire so that the wide surface of the conductive wire extends in a direction perpendicular to the winding axis of coils 3a and 3b. For example, flatwise coils can also be used for coils 3a and 3b.

[0029] These coils 3a, 3b have a rectangular cylindrical shape, and are defined by a first end face 32a, a second end face 32b, and a peripheral surface 31 connecting the first end face 32a and the second end face 32b. The first end face 32a and the second end face 32b are located at the start and end of the winding of the conductive wire, and are perpendicular to the cylindrical axis (X-axis direction). The first end face 32a and the second end face 32b have an annular shape to match the winding pattern of the conductive wire.

[0030] The peripheral surface 31 of the coils 3a and 3b is composed of four flat surfaces that are perpendicular to the first end surface 32a and the second end surface 32b and parallel to the cylindrical axis. That is, the coils 3a and 3b have a flat upper surface 31a that is parallel to the plane where the annular shape of the core 2 appears, and a flat lower surface 31b on the opposite side to the upper surface 31a. The coils 3a and 3b have two flat side surfaces 31c that are perpendicular to the upper surface 31a and the lower surface 31b.

[0031] The top surface 31a is one of the surfaces of the circumferential surface 31 of the coils 3a and 3b that is parallel to the arrangement direction of the coils 3a and 3b. When the coils 3a and 3b are viewed from the top surface 31a, the coils 3a and 3b appear to be side by side without overlapping. The bottom surface 31b is the surface of the circumferential surface 31 of the coils 3a and 3b that is parallel to the arrangement direction of the coils 3a and 3b and is located on the back side of the top surface 31a. The side surface 31c is a surface that is perpendicular to the arrangement direction of the coils 3a and 3b. When the coils 3a and 3b are viewed from the side surface 31c, the coils 3a and 3b appear to be overlapping.

[0032] The flat surfaces of the coils 3a and 3b include surfaces that form large arcs with gentle curvatures due to the bulging of the conductive wires. The top surface 31a, the side surface 31c, and the bottom surface 31b are connected by curved boundaries. The terms "upper" and "lower" refer to the upper and lower molds that house the coils 3a and 3b when they are covered by molding, and do not refer to the positional relationship or orientation when the reactor 1 is mounted on an actual device to be installed.

[0033] Coil 3a and coil 3b form a single linked coil, and are arranged in parallel to obtain a high inductance value in a large current region, and are linked so that the currents flowing through the two coils are in opposite directions. Coil 3a and coil 3b are linked on the second end surface 32b side.

[0034] A lead wire 4a and a lead wire 4b are respectively drawn out from the first end surfaces 32a of the coils 3a and 3b. The lead wire 4a is drawn out from the coil 3a, and the lead wire 4b is drawn out from the coil 3b. The lead wires 4a and 4b are connected to a bus bar (not shown) for inputting and outputting current with the outside. The bus bar is a connecting conductor for connecting to other devices in the circuit, and is, for example, a long plate with a conductor such as copper drawn out. The lead wires 4a and 4b are connected to the respective bus bars by welding or the like. By connecting the terminals of other devices in the circuit to this bus bar, current is supplied from the outside to the coils 3a and 3b.

[0035] The lead wire 4a drawn from the coil 3a is bent at a right angle within the first end surface 32a so as to be along the cylindrical axis of the coil 3a, and extends along the cylindrical axis of the coil 3a. The lead wire 4b drawn from the coil 3b extends along the first end surface 32a so as to be perpendicular to the cylindrical axis of the coil 3b, protrudes out of the coil 3a from the side surface 31c farthest from the coil 3a, bent at a right angle so as to be along the cylindrical axis of the coil 3b, and extends along the cylindrical axis of the coil 3b.

[0036] That is, the lead wire 4b includes an extending portion 41, a bent portion 42, and an extension portion 43. The extending portion 41 is drawn out from the first end surface 32a and extends along the first end surface 32a to the outside of the coil 3b. The bent portion 42 is bent at a right angle from the direction along the first end surface 32a to the direction along the cylindrical axis of the coil 3b. The extension portion 43 extends from the bent portion 42 along the cylindrical axis of the coil 3b.

[0037] Fig. 2 is a perspective view showing molded coil 5. Fig. 3 is a perspective view showing molded coil 5, omitting molded resin 10 for ease of explanation. As shown in Figs. 2 and 3, coils 3a and 3b are covered with coil-coating resin 6, and together with this coil-coating resin 6, they form molded coil 5. Note that core 2 may also be partially or entirely covered with a separate molded resin, and molded coil 5 and core 2 may further be partially or entirely covered with a separate molded resin.

[0038] The coil coating resin 6 protects the coils 3a, 3b from mechanical shock and also covers at least the areas where the coils 3a, 3b are close to the core 2, thereby electrically insulating the coils 3a, 3b from the core 2. In addition, the coils 3a, 3b are coated with the coil coating resin 6, which suppresses vibration of the coils 3a, 3b. The coils 3a, 3b are mounted on the core 2 in the form of molded coils 5.

[0039] Examples of materials for the coil coating resin 6 include epoxy resin, unsaturated polyester resin, urethane resin, BMC (Bulk Molding Compound), PPS (Polyphenylene Sulfide), PBT (Polybutylene Terephthalate), and composites of these, and these have insulating and heat-resistant properties. A thermally conductive filler may be mixed into the coil coating resin 6.

[0040] The coil coating resin 6 is composed of an upper spacer 7, an end surface spacer 8, a lower spacer 9, and a molded resin 10, which are combined to cover the coils 3a and 3b. The upper spacer 7 covers part of the upper surfaces 31a of the coils 3a and 3b and extends to part of the second end surfaces 32b. The end surface spacer 8 covers part of the first end surfaces 32a and inner surfaces of the coils 3a and 3b. The lower spacer 9 covers the lower surfaces 31b, part of the side surfaces 31c, and the second end surfaces 32b of the coils 3a and 3b.

[0041] The upper spacers 7, 7 of the coils 3a and 3b are connected at a connection 75 and are molded seamlessly as a single piece. The end surface spacers 8, 8 of the coils 3a and 3b are the same shape and size. The lower spacers 9, 9 of the coils 3a and 3b are molded seamlessly as a single piece. The lower spacer 9 is a frame with an opening, and the lower surface 31b is exposed except for the peripheral edge.

[0042] The molded resin 10 covers the uncoated areas of the upper spacer 7, end surface spacers 8, and lower spacer 9 by placing the coils 3a, 3b, to which the upper spacer 7, end surface spacers 8, and lower spacer 9 are assembled, in a mold, and then injecting resin into the mold and solidifying it. The lower surface 31b exposed from the lower spacer 9 is also left exposed and not covered by the molded resin 10. In addition to covering the coils 3a, 3b, the molded resin 10 also has formed therein a terminal block 51 for installing a bus bar and a sensor member installation portion 62 for installing a sensor member such as a thermistor, which are formed by molding.

[0043] FIG. 4 is a perspective view showing an upper spacer 7 of such coil coating resin 6. Note that the dotted lines in FIG. 4 are lines for convenience of explanation and are lines for illustrating the region of connecting plate 73a. As shown in FIG. 4, the upper spacer 7 includes a plate body 71 and a buried portion 74. The plate body 71 is an oval plate that rests on the upper surface 31a of each coil 3a, 3b. The upper surface 71a of the plate body 71, i.e., the surface opposite to the surface facing the upper surface 31a of the coils 3a, 3b, is a flat surface that extends parallel to the upper surface 31a.

[0044] The buried portion 74 is a flat surface that extends around the entire periphery of the plate body 71, and extends to the upper surface 31a of each coil 3a, 3b, or to the curved region at the boundary between the upper surface 31a and the side surface 31c. The buried portion 74 extends parallel to the upper surface 31a of the coils 3a, 3b, but is one step lower than the plate body 71. The plate body 71 bulges out from the buried portion 74 and is one step higher. In other words, the plate body 71 is thicker than the buried portion 74, and the buried portion 74 is thinner than the plate body 71.

[0045] The upper spacer 7 is a seamless, integrally molded product, and the plate 71 and buried portion 74 extending over the coil 3a also extend seamlessly, and the plate 71 and buried portion 74 extending over the coil 3b also extend seamlessly. The upper spacer 7 over the coil 3a and the upper spacer 7 over the coil 3b are also seamlessly molded products, and a connecting portion 75 extends between the two upper spacers 7 to connect them.

[0046] The connecting portions 75 are multiple linear members bridging between the coils 3a and 3b, and have the same thickness as the buried portions 74. They are curved to follow the outer shapes of the coils 3a and 3b and are disposed between the upper spacers 7 along the alignment direction of the coils 3a and 3b. The connecting portions 75 function as positioning members that place the upper spacers 7 on the coils 3a and 3b, or as positioning members that increase the accuracy of the spacing between the coils 3a and 3b.

[0047] The linear members of connecting portion 75 are arranged at intervals, with openings between the linear members. Molding resin 10 flows in through these openings, thereby covering side surface 31c where coils 3a and 3b face each other with molding resin 10.

[0048] The upper spacer 7, which is installed on the coil 3b from which the lead wire 4b is drawn, further includes a wire plate 72a that covers the lead wire 4b. The lead wire 4b has an extending portion 41 extending along the first end surface 32a, a bent portion 42 that bends from the extending portion 41 in the axial direction of the coil 3b, and an extension portion 43 that extends from the bent portion 42 in the axial direction of the coil 3b. The wire plate 72a extends parallel to the upper surface 31a of the coil 3b and the upper surface 71a of the plate body 71. The wire plate 72a covers the lead wire 4b from the boundary between the extending portion 41 and the bent portion 42, including the entire bent portion 42, to the boundary between the bent portion 42 and the extension portion 43.

[0049] Incidentally, a portion of the boundary area of ​​the wire plate 72a with the connecting plate 73a is cut out to make it thinner, and a portion of the boundary area of ​​the wire plate 72a with the connecting plate 73a also forms a buried portion 74. The lead wire 4a of the coil 3a is also covered with a wire cover 81, and the wire cover extends from an end surface spacer 8 that covers the first end surface 32a of the coil 3a (see FIG. 3).

[0050] The wire plate 72a and the plate body 71 of the coil 3b are connected by a connecting plate 73a. The connecting plate 73a extends between the plate body 71 and the wire plate 72a along the extending portion 41 of the lead wire 4b. However, in this molded core 3, an embedded portion 74 protrudes from the periphery of the plate body 71. Therefore, the connecting plate 73a is continuous with the embedded portion 74 around the periphery of the plate body 71, connecting the plate body 71 and the wire plate 72a. In other words, in this molded coil 5, in addition to the connecting plate 73a, the embedded portion 74 is interposed on the plate body 71 side between the plate body 71 and the wire plate 72a.

[0051] Here, linear plate 72a bulges out at least more than buried portion 74 and may have the same thickness as plate body 71. On the other hand, connecting plate 73a is thinner than plate body 71 and linear plate 72a, and is less rigid and more flexible than plate body 71 and linear plate 72a. The thickness of connecting plate 73a may be the same as or thinner than buried portion 74, for example. The width (X direction) of connecting plate 73a, i.e., the length in the cylindrical axis direction (X direction) perpendicular to the longitudinal direction (Y direction) connecting plate body 71 and linear plate 72a, is narrower than the width in the cylindrical axis direction (X direction) of buried portion 74 around plate body 71, thereby reducing the effect of the low rigidity of connecting plate 73a.

[0052] The wire plate 72a is a part of the wire cover 72 provided in the upper spacer 7. The wire cover 72 has a U-shape formed by the wire plate 72a and the side surfaces 72b on two sides, and covers the lead wire 4b from three adjacent directions, including the top side (positive direction of the Z axis). The connecting plate 73a is a part of the connecting portion 73 provided in the upper spacer 7. The connecting portion 73 has a U-shape formed by the connecting plate 73a and the side surfaces 73b on two sides, and covers the lead wire 4b from three adjacent directions, including the top side (positive direction of the Z axis).

[0053] The side surface 73b of the connecting portion 73 and the side surface 72b of the wire cover 72 are connected flush with each other without any boundary. However, the width of the side surface 73b of the connecting portion 73 extending downward (in the negative Z-axis direction) from the upper surface 31a toward the lower surface 31b of the coil 3b is narrower than that of the side surface 72b of the wire cover 72, and is also narrower than the wide surface of the lead wire 4b. In other words, the side surface 73b of the connecting portion 73 is narrow so as to minimize the effect of compromising the low rigidity of the connecting plate 73a. In this molded coil 5, the side surface 73b of the connecting portion 73 is arched so that the width increases smoothly from the side surface 73b of the connecting portion 73 to the side surface 72b of the wire cover 72.

[0054] The upper spacer 7, including the above-mentioned wire cover 72 and connecting portion 73, is a seamless, integrally molded product, and the plate body 71 and buried portion 74 extending over the coil 3b, the connecting portion 73 along the lead wire 4b and the wire cover 72 covering the lead wire 4b, and the buried portion 74 at the boundary between the connecting plate 73a and the wire plate 72a also extend seamlessly.

[0055] Fig. 5 is a perspective view showing coils 3a and 3b with an upper spacer 7 installed, and Fig. 6 is a schematic diagram showing a cross section of molded coil 5. As shown in Fig. 5, after the upper spacer 7 is installed on coils 3a and 3b, coils 3a and 3b are placed in a mold, and resin that will become molding resin 10 is injected into the mold. Although omitted from Fig. 5 for convenience of explanation, end surface spacers 8 and lower spacers 9 are also installed on coils 3a and 3b in addition to the upper spacer 7, and then the coils are placed in the mold.

[0056] The mold is divided into at least an upper mold located on the upper surface 31a side of the coils 3a and 3b, and a lower mold located on the lower surface 31b of the coils 3a and 3b. By bringing the upper mold and lower mold together, the coils 3a and 3b are sealed inside the mold, and resin that becomes the molding resin 10 is injected into the gap between the coils 3a and 3b and the mold.

[0057] The upper mold has a movable mold Ma that presses the plate body 71 of the upper spacer 7, and a fixed mold Mf that grips the wire cover 72. The movable mold Ma presses the entire upper surface 71a of the plate body 71. This movable mold Ma is positionally adjustable and descends until twists and irregularities present on the peripheral surfaces 31 of the coils 3a and 3b are corrected and the entire upper surface 31a of the coils 3a and 3b is smooth. In other words, the movable mold Ma descends until it receives the resistance force generated when the entire upper surface 31a of the coils 3a and 3b is smooth. Meanwhile, the fixed mold Mf is fixed in a specified position and presses the wire upper plate 72a of the wire cover 72.

[0058] 6, when resin is injected into the mold, molding resin 10 is formed around the coils 3a and 3b. Because the plate body 71 and the movable mold Ma are in contact within the mold, the upper surface 71a of the plate body 71 is exposed from the molding resin 10. Because the wire plate 72a of the wire cover 72 and the fixed mold Mf are in contact within the mold, the wire plate 72a of the wire cover 72 is exposed from the molding resin 10.

[0059] The buried portion 74 and the connecting portion 73 are buried in the molded resin 10. In particular, because the buried portion 74 is covered by the molded resin 10, even if the connecting portion 73 is prone to bending as described below, the plate body 71 and the wire cover 72 are prevented from floating up and becoming detached from the molded coil 5. In particular, because the buried portion 74 is also formed at the boundary between the wire cover 72 and the connecting portion 73, the wire cover 72 is effectively prevented from floating up. Furthermore, the end of the wire cover 72 on the extension portion 43 side is gripped from all sides by the mold and is exposed from the molded resin 10. A parting line appears at the end of the wire cover 72 on the extension portion 43 side.

[0060] 7 is a schematic diagram showing the upper spacer 7 when the coil 3b is wound with high precision. As shown in FIG. 7, when the thicknesses of the plate body 71 and the wire plate 72a of the wire cover 72 are the same and the coil 3b is wound with high precision without twists or unevenness, the lower end position Hf of the fixed mold Mf and the lower end position HaB of the movable mold Ma coincide. Therefore, no stress is applied to the connecting portion 73, and the connecting plate 73a remains extended linearly.

[0061] 8 is a schematic diagram showing the upper spacer 7 when the coil 3b is wound so that the diameter thereof is larger overall. If the diameter of each turn of the conductive wire in the coil 3b is larger than the specified diameter overall, when the twists and irregularities in the peripheral surface 31 of the coil 3b are corrected to make the peripheral surface 31 flat, the movable mold Ma will stop at a lower end position HaH that is higher than the intended lower end position HaB.

[0062] Assume that the thickness of the connecting plate 73a is the same as that of the plate body 71 and the linear plate 72a, has high rigidity, and is difficult to bend. Since the fixed mold Mf descends to the specified lower end position Hf, if the connecting plate 73a maintains a straight line without bending, the upper spacer 7 will be tilted overall so that the movable mold Ma side is higher and the fixed mold Mf side is lower.

[0063] In this case, there is a risk that the lead wire 4b will be twisted inward due to the force from the wire cover 72. If the lead wire 4b is twisted and the positioning accuracy deteriorates, it will be difficult to install the bus bar welded to the lead wire 4b on the terminal block 51, making it difficult to easily and accurately install the molded coil 5 on the reactor 1. Furthermore, the terminal block 51 may be distorted, making it difficult to easily and accurately install the reactor 1 on the circuit.

[0064] However, in this molded coil 5, the connecting plate 73a is thinner and less rigid than the plate body 71 and the wiring plate 72a. Therefore, as shown in Figure 8, even if the heights of the movable mold Ma and the fixed mold Mf are different, the connecting plate 73a bends first, so the wiring cover 72 does not tilt and the lead wire 4b does not twist, maintaining high positional accuracy. Therefore, the bus bar to be welded to the lead wire 4b can be easily and accurately installed on the terminal block 51, and the molded coil 5 can be easily and accurately installed on the reactor 1. Furthermore, the terminal block 51 is less likely to warp, allowing the reactor 1 to be easily and accurately installed on the circuit.

[0065] 9 is a schematic diagram showing the upper spacer 7 when the coil 3b is wound so that the diameter thereof is small overall. If the diameter of each turn of the conductive wire in the coil 3b is smaller than the specified diameter overall, when the twists and irregularities in the peripheral surface 31 of the coil 3b are corrected to make the peripheral surface 31 flat, the movable mold Ma will stop at a lower end position HaL that is lower than the intended lower end position HaB.

[0066] It is assumed that the thickness of the connecting plate 73a is the same as that of the plate body 71 and the linear plate 72a, that the connecting plate 73a is highly rigid, and that the connecting plate 73a is difficult to bend. Since the fixed mold Mf descends to the specified lower end position Hf, if the connecting plate 73a maintains a straight line without bending, the upper spacer 7 will be tilted overall so that the movable mold Ma side is lower and the fixed mold Mf side is lower.

[0067] As a result, there is a risk that the lead wires 4b will be twisted outward due to the force from the line cover 72. Furthermore, the line cover 72 will float relative to the lead wires 4b, making it impossible to firmly hold the lead wires 4b within the mold, and the lead wires 4b will be blown by the injection pressure of the resin, which could result in a deterioration in the positional accuracy of the lead wires 4b. If the positional accuracy of the lead wires 4b deteriorates due to twisting or blowing, it will be difficult to install the bus bar welded to the lead wires 4b on the terminal block 51, making it difficult to easily and accurately install the molded coil 5 on the reactor 1. Furthermore, the terminal block 51 may be distorted, making it difficult to easily and accurately install the reactor 1 on the circuit.

[0068] However, in this molded coil 5, the connecting plate 73a is thinner and less rigid than the plate body 71 and the wiring plate 72a. Therefore, as shown in Figure 9, even if the heights of the movable mold Ma and the fixed mold Mf are different, the connecting plate 73a bends first, so the wiring cover 72 does not tilt and the lead wire 4b does not twist, maintaining high positional accuracy. Therefore, the bus bar to be welded to the lead wire 4b can be easily and accurately installed on the terminal block 51, and the molded coil 5 can be easily and accurately installed on the reactor 1. Furthermore, the terminal block 51 is less likely to warp, allowing the reactor 1 to be easily and accurately installed on the circuit.

[0069] In particular, when the lead wire 4b has an extending portion 41 extending perpendicular to the cylindrical axis of the coil 3b and further has a bent portion 42 and an extended portion 43 extending in a direction parallel to the cylindrical axis of the coil 3b, the lead wire 4b extends long within the mold. Therefore, the lead wire 4b is easily twisted and blown by the injection pressure. Therefore, such a molded coil 5 is particularly suitable for the lead wire 4b.

[0070] As described above, this molded coil 5 and reactor 1 include a cylindrical coil 3b which is a wound body of conductive wire, a lead wire 4b drawn out from the end face of the coil 3b, and a coil coating resin 6 which coats part or all of the coil 3b and is interposed between the core 2 and the coil 3b.

[0071] This coil coating resin 6 has a plate body 71, a wire plate 72a, a connecting plate 73a, and molded resin 10. The plate body 71 covers a portion of the peripheral surface of the coil 3b, the wire plate 72a covers a portion of the lead wire 4b, the connecting plate 73a connects the plate body 71 and the wire plate 72a, and the molded resin 10 covers all or part of the surface of the coil 3b except for the area covered by the plate body 71 and the wire plate 72a. In such a molded coil 5 and reactor 1, the connecting plate 73a has lower rigidity than the plate body 71 and the wire plate 72a.

[0072] As a result, even if the heights of the movable mold Ma and the fixed mold Mf are different when molding the molded resin 10, the connecting plate 73a bends first, preventing the wire cover 72 from tilting and the lead wires 4b from twisting or being blown around by the resin injection pressure, maintaining high positional accuracy. As a result, the bus bar to be welded to the lead wires 4b can be easily and accurately installed on the terminal block 51, and the molded coil 5 can be easily and accurately installed on the reactor 1. Furthermore, the terminal block 51 is less likely to warp, allowing the reactor 1 to be easily and accurately installed on the circuit.

[0073] In order to make the connecting plate 73a low in rigidity, the plate body 71 and the linear plate 72a are made of plates that are relatively thicker than the connecting plate 73a, and the connecting plate 73a is made of plates that are relatively thinner than the plate body 71 and the linear plate 72a. However, this is not limitative, and the low rigidity of the connecting plate 73a may be realized by various methods.

[0074] Furthermore, the coil coating resin 6 is provided with an embedded portion 74. The embedded portion 74 is thinner than the plate body 71 and the wire plate 72a and is embedded in the molded resin 10 over a part or the entire periphery of the plate body 71 and the wire plate 72a. This makes it easier for the plate body 71 and the wire plate 72a to maintain their positions even if the connecting plate 73a is prone to bending, and prevents them from coming off the coil 3b and floating up.

[0075] Furthermore, the length of connecting plate 73a warped in the axial direction of coil 3b is narrower than buried portion 74 around plate body 71. Also, connecting plate 73a has side surface portions 73b that stand upright in the thickness direction of connecting plate 73a and cover lead wire 4b together with connecting plate 73a, but side surface portions 73b are shorter than the width of the wide surface of lead wire 4b. This does not affect the low rigidity of connecting plate 73a and does not impair the flexibility of connecting plate 73a.

[0076] The lead wire 4b of the coil 3b on which such an upper spacer 7 is installed is perpendicular to or drawn out from the cylindrical axis of the coil 3b, or is further bent in a direction along the cylindrical axis of the coil 3b. Therefore, the lead wire 4b extends long within the mold and is easily twisted and blown. Therefore, this plate body 71 functions particularly well. Note that if the lead wire 4b extends long within the mold, the plate body 71 functions particularly well, and the lead wire 4b may extend in a direction oblique to the cylindrical axis of the coil 3b.

[0077] The above-described embodiments of the present invention are presented as examples, and the present invention is not limited to the above-described embodiments. The above-described embodiments 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 embodiments and their modifications are included in the scope of the present invention.

[0078] For example, the core 2 may be partially or completely coated with resin, or the surfaces of the resin-coated core 2 and molded coil 5 may be further molded with resin to integrate the core 2 and molded coil 5. [Explanation of symbols]

[0079] 1 reactor 2 cores 3a, 3b coil 31 Peripheral surface 31a Top surface 31b Bottom side 31c side 32a 1st end face 32b 2nd end face 4a,4b leader line 41 Extension part 42 Bend 43 Extension 5 Molded coil 51 Terminal block 52 Sensor component installation section 6 Coil coating resin 7 Upper spacer 71 Plate 71a Top side 72 Wire Cover 72a wire top plate 72b Side part 73 Connecting part 73a Connecting plate 73b Side part 74 Burial part 75 Connection 8 End face spacer 81 Wire Cover 9 Lower spacer 10 Molding resin Ma Movable mold Mf Fixed mold

Claims

1. a cylindrical coil that is a wound body of conductive wire; a lead wire drawn out from an end surface of the coil; a coil coating resin that coats a part or all of the coil; Equipped with The coil coating resin is a plate body covering a partial area on the circumferential surface of the coil; a wiring plate that covers a part of the lead wire; a connecting plate that connects the plate body and the linear plate; a molding resin that covers all or part of the surface of the coil except for the area covered by the plate body and the wiring plate; and the connecting plate has lower rigidity than the plate body and the linear plate, the coil coating resin has an embedded portion that is thinner than the plate body and the wire plate and is embedded in the molding resin around a part or the entire periphery of the plate body and the wire plate, the connecting plate is connected to the plate body via the buried portion; A molded coil characterized by:

2. The plate body and the linear plate are made of plates that are relatively thick compared to the connecting plate, the connecting plate is made of a plate that is relatively thin compared to the plate body and the linear plate; 2. The molded coil according to claim 1, wherein:

3. The connecting plate has a surface narrower than the buried portion and extends between the plate body and the linear plate; 3. The molded coil according to claim 1 or 2, characterized in that:

4. a side surface portion that stands upright from the connecting plate in a thickness direction of the connecting plate and covers the lead wire together with the connecting plate; the side surface portion has a height shorter than the width of the wide surface of the lead wire; 4. The molded coil according to claim 1, wherein:

5. the plate has a mold contact surface that comes into contact with a mold when the molding resin is formed; 5. The molded coil according to claim 1, wherein:

6. The lead wire is drawn out in a direction perpendicular or oblique to the cylindrical axis of the coil; 6. The molded coil according to claim 1, wherein:

7. the lead wire is drawn out in a direction perpendicular or oblique to the cylindrical axis of the coil, and is further bent in a direction along the cylindrical axis of the coil; 6. The molded coil according to claim 1, wherein:

8. A molded coil according to any one of claims 1 to 7; a core including a magnetic material and on which the molded coil is mounted; A reactor comprising:

Images