Mold coil, reactor, manufacturing method of the mold coil, and manufacturing method of the reactor

Abstract

To provide a mold coil, a reactor, and a manufacturing method of them, capable of enabling mounting of a cover, and suppressing inflow of a resin to an exposure surface.SOLUTION: A mold coil comprises: a coil 2; a cylinder cover 5 that is inserted into an inner periphery of the coil 2 and covers an inner peripheral surface of the coil 2; and a coil mold resin part that covers the coil 2 and the cylinder cover 5. The coil 2 includes: a side surface leading wire 26 that is extended along a direction orthogonal to a side surface of the coil 2; and an exposure surface 22 that is not coated with the coil mold resin part, and is exposed. The side surface leading wire 26 is led from the side surface of the exposure surface 22 side, and the cylinder cover 5 includes a leading wire protection part 54 that protects the side surface leading wire 26. The leading wire protection part 54 includes: a long side part that is crossed to a winding shaft, and is extended along the winding shaft from a wall part that is opposite to an opposite surface 261 of the side surface leading wire 26 positioned at an annular shape surface 24 side where the side surface leading wire 26 is led, and one end part of the wall part, and is opposite to an upper surface of the side surface leading wire 26; and an open that is a space of a lower direction of the long side part.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a molded coil, a reactor, a manufacturing method of a molded coil, and a manufacturing method of a reactor. [Background technology]

[0002] Coil components are used in a variety of applications, including office automation equipment, solar power generation systems, and automobiles. An example of a coil component is a reactor. A reactor is an electromagnetic component that converts electrical energy into magnetic energy and stores and releases the energy.

[0003] The coil component mainly includes a core, a coil, and a resin member. The core is made of a magnetic material, such as a powder magnetic core. The coil is wound around the outer periphery of the core. A resin member is provided between the core and the coil to insulate them from each other.

[0004] In recent years, molded coils made of resin are widely used. The coil is placed in a predetermined position in a mold, resin is injected into the mold, and the resin is allowed to harden. In this way, a molded coil is produced in which the coil is covered with a resin.

[0005] The coil winding variations are corrected by applying pressure using a mold, a pressing member, or the injected resin. In this process, a resin cover may be placed around the coil to prevent the mold, pressing member, or injected resin from coming into direct contact with the coil. Furthermore, when an exposed surface is provided on the coil, the mold and resin cover are abutted against each other to block the inflow path of the resin.

[0006] The resin cover may have an inner circumferential surface protective portion that covers the inner circumferential surface of the coil or a side surface protective portion that covers the side surface of the coil. A cover having an inner circumferential surface protective portion or a side surface protective portion further has a lead wire protective portion that covers the periphery of the lead wire of the coil. Since this cover has an inner circumferential surface protective portion or a side surface protective portion, it is attached to the coil along the winding axis. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent Publication No. 2022-188850 Summary of the Invention [Problem to be solved by the invention]

[0008] When the coil's lead wire extends from a side surface near the exposed surface of the coil in a direction perpendicular to the side surface, the extension direction of the lead wire intersects with the insertion direction of the cover. In order to prevent the cover and the lead wire from interfering with each other when the cover is attached, the cover becomes complicated. In addition, as the cover becomes more complicated, the mold also becomes more complicated, which results in a decrease in adhesion between the cover and the mold, and there is a risk of resin leaking onto the exposed surface.

[0009] The present invention has been made to solve the above-mentioned problems, and its object is to provide a molded coil and a reactor that allows a cover to be attached to a coil having a lead wire that is drawn out in a direction perpendicular to the side of the coil, and that can suppress the flow of resin into the exposed surface. [Means for solving the problem]

[0010] In order to solve the above-mentioned problems, the molded coil of this embodiment includes a coil, a cover covering an inner surface of the coil or a side surface of the coil, and a coil molded resin part covering the coil and the cover, wherein the coil has an annular surface which is an end surface perpendicular to a winding axis, a side lead wire extending along a direction perpendicular to the side surface of the coil, and an exposed surface which is not covered by the coil molded resin part and is exposed, the side lead wire is drawn out from the exposed surface side of the annular surface, the cover has an annular surface protection part which protects the annular surface, and a lead wire protection part which protects the side lead wire, wherein the lead wire protection part has: a wall part which is perpendicular to the winding axis and faces an end surface of the side lead wire located on the annular surface side from which the side lead wire is drawn out, a first extension part which extends from one end of the wall part along the winding axis and faces an upper surface of the side lead wire, and an opening which is a space below the first extension part.

[0011] A reactor in which a core including a magnetic material is attached to the molded coil is also one aspect of the present invention.

[0012] Furthermore, a reactor in which a core including a magnetic material is attached to the molded coil and a method for manufacturing the reactor are also aspects of the present invention. Effect of the Invention

[0013] According to the present invention, it is possible to obtain a molded coil and a reactor that enable a cover to be attached to a coil having a lead wire that is drawn out in a direction perpendicular to the side of the coil, and that can suppress the flow of resin into the exposed surface. [Brief description of the drawings]

[0014] [Figure 1] FIG. 2 is a perspective view showing the overall configuration of a molded coil. [Diagram 2] FIG. 4 is a perspective view showing a state in which a cover is attached to the coil. [Diagram 3] FIG. 4 is an exploded perspective view showing a state before a cover is attached to the coil. [Figure 4]FIG. [Diagram 5] FIG. [Figure 6] FIG. 13 is a perspective view showing a side lead wire attached to a lead wire protection portion. [Figure 7] FIG. 4 is an enlarged side view of the lead wire protection portion. [Figure 8] FIG. 2 is a perspective view showing the overall configuration of a reactor. [Figure 9] FIG. 11 is a side view showing the state of the coil placed in the mold during the molding process. [Figure 10] 13A and 13B are diagrams illustrating a configuration of a lead wire protection unit according to another embodiment. [Figure 11] 13A and 13B are diagrams illustrating a configuration of a lead wire protection unit according to another embodiment. [Figure 12] 13 is a diagram showing a state in which a lead wire protection part and a die are in contact with each other in another embodiment. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] (Embodiment) A molded coil according to an embodiment will be described with reference to the drawings. Fig. 1 is a perspective view showing the overall configuration of the molded coil. Fig. 2 is a perspective view showing a state in which a cover is attached to the coil. Fig. 3 is an exploded perspective view showing a state before the cover is attached to the coil. In each drawing, thickness, dimensions, positional relationship, ratio, shape, etc. may be emphasized for ease of understanding, but the present invention is not limited to such emphasis.

[0016] The molded coil 1 is a main component of a coil part such as a reactor. As shown in Figs. 1 to 3, the molded coil 1 includes a coil 2, an upper cover 3, an annular cover 4, a cylindrical cover 5, and a coil molded resin part 6. The upper cover 3, the annular cover 4, and the cylindrical cover 5 are each produced as separate bodies. The upper cover 3, the annular cover 4, and the cylindrical cover 5 are attached to the coil 2. The molded coil 1 is produced by molding the coil 2, the upper cover 3, the annular cover 4, and the cylindrical cover 5 with a resin that forms the coil molded resin part 6.

[0017] Coil 2 is composed of a single conductive member that is insulated with enamel or the like. Coil 2 is formed by winding the conductive member into a cylindrical shape while shifting the winding position in the winding axis direction. The conductive member is, for example, a rectangular wire, and coil 2 is an edgewise coil in which the wide surface of the conductive member extends in a direction perpendicular to the winding axis of coil 2. Coil 2 may also be a flatwise coil.

[0018] There are provided two coils 2. The two coils 2 are arranged side by side so that their winding axes are parallel. In this embodiment, the two coils 2 are connected by a connecting wire 21 to form a connected coil.

[0019] The coil 2 is formed in a square tube shape with four flat surfaces and four curved surfaces arranged alternately. The coil 2 has an exposed surface 22 that is not covered by the covers 3, 4, 5 and the coil mold resin part 6. The exposed surface 22 is formed on the lower surface of the coil 2. That is, the exposed surface 22 exposes the flat and curved parts that form the lower surface of the coil 2. Note that the up-down direction refers to a direction perpendicular to the winding axis and perpendicular to the lateral arrangement direction of the coil 2, and during molding, the end surface facing the upper die is the upper surface of the coil 2, and the end surface facing the lower die is the lower surface of the coil 2.

[0020] Coil 2 has annular surfaces 23 and 24 that are perpendicular to the winding axis. Connecting wire 21 is arranged on annular surface 23. Annular surface 24 is the surface opposite to annular surface 23, and has lead wire 25 or side lead wire 26 led out from it. Lead wire 25 and side lead wire 26 are connected to a bus bar (not shown) and electrically connected to an external device via the bus bar.

[0021] The lead wire 25 is formed on the lower surface side of the coil 2 of the annular surface 24, i.e., on the exposed surface 22 side. The lead wire 25 is drawn out from the annular surface 24 along the winding axis. The side lead wire 26 is formed on the lower surface side of the coil 2 of the annular surface 24, i.e., on the exposed surface 22 side. The side lead wire 26 is drawn out from the annular surface 24 along the lateral arrangement direction of the coil 2. The side lead wire 26 is drawn out in a direction perpendicular to the side surface of the coil 2, i.e., in a direction intersecting the winding axis. The side lead wire 26 is drawn out so that the wide surface of the conductive member is perpendicular to the winding axis. The side lead wire 26 has an opposing surface 261. The opposing surface 261 is an end surface of the side lead wire 26 that faces a wall portion 541 of the lead wire protection portion 54 described later, among the end surfaces perpendicular to the winding axis. The opposing surface 261 is located on the annular surface 24 side. In other words, the opposing surface 261 is provided at a position farther away from the annular surface 23 than the other end surface perpendicular to the winding axis.

[0022] The upper cover 3, the annular cover 4, and the cylindrical cover 5 cover the periphery of the coil 2. The upper cover 3, the annular cover 4, and the cylindrical cover 5 prevent the coil 2 from directly contacting the mold, the pressing member, or the injected resin during molding.

[0023] The upper cover 3, the annular cover 4, and the cylindrical cover 5 are made of resin. Examples of the types of resin include epoxy resin, unsaturated polyester resin, urethane resin, BMC (Bulk Molding Compound), PPS (Polyphenylene Sulfide), and PBT (Polybutylene Terephthalate).

[0024] The upper cover 3 covers the upper surface of the coil 2. The upper cover 3 has an upper surface protection portion 31, a connecting portion 32, and a protruding portion 33. The upper surface protection portion 31 covers a flat portion located on the upper surface of the coil 2. The upper surface protection portion 31 is a flat plate-shaped member. Two upper surface protection portions 31 are provided.

[0025] The connecting portion 32 is provided between the two upper surface protection portions 31 and connects the upper surface protection portions 31. The connecting portion 32 has a shape following the curved portion of the coil 2. The protruding portion 33 is a flat plate-shaped member. It protrudes downward from one end of the upper surface protection portion 31 below the coil 2. In other words, when the upper cover 3 is attached to the coil 2, the protruding portion 33 faces the annular surface 23.

[0026] The annular cover 4 covers the annular surface 23 of the coil 2. The annular cover 4 has an annular surface protection portion 41, a side protection portion 42, and a central extension portion 43. The annular surface protection portion 41 is a ring-shaped member having an opening that is approximately the same as the inner diameter of the coil 2. The annular surface protection portion 41 covers the annular surface 23 of the coil 2. Two annular surface protection portions 41 are provided, and are formed continuously by a connecting portion 411.

[0027] Side surface protective portion 42 covers the outer surface of coil 2. The side surface of coil 2 is a surface perpendicular to the lateral arrangement direction of coil 2, the side surface that each coil 2 faces is called the inner surface, and the side surface opposite the inner surface is called the outer surface. Side surface protective portion 42 extends from annular surface protective portion 41 along the winding axis. It is sufficient for side surface protective portion 42 to cover at least a portion of the outer surface.

[0028] The central extending portion 43 is provided between the coils 2. The central extending portion 43 extends along the winding axis from a connecting portion 411 that connects the two annular surface protection portions 41. The central extending portion 43 covers the inner surface of the coil 2.

[0029] The cylindrical cover 5 is inserted into the inner circumference of the coil 2 to cover the inner circumferential surface of the coil 2. Two cylindrical covers 5 are provided. The cylindrical cover 5a is inserted into the inner circumference of the coil 2 having the lead wire 25. The cylindrical cover 5b is inserted into the inner circumference of the coil 2 having the side lead wire 26.

[0030] As shown in Fig. 3, the cylindrical covers 5a, 5b have an inner circumferential surface protection portion 51 and an annular surface protection portion 52. The inner circumferential surface protection portion 51 covers the inner circumferential surface of the coil 2. The inner circumferential surface protection portion 51 is cylindrical and has an outer shape following the inner circumferential surface of the coil 2. The inner circumferential surface protection portion 51 extends from the annular surface protection portion 52 along the winding axis.

[0031] The annular surface protection portion 52 covers the annular surface 24 of the coil 2. The annular surface protection portion 52 is in a ring shape with an opening that is approximately the same as the inner diameter of the inner surface protection portion 51. The annular surface protection portion 52 extends from the end of the inner surface protection portion 51 on the annular surface 24 side of the winding shaft. The annular surface protection portion 52 comes into contact with a mold or a jig during molding.

[0032] The cylindrical cover 5a has a lead wire protection portion 53. The lead wire protection portion 53 extends from the underside of the annular surface protection portion 52 along the winding axis. The lead wire protection portion 53 has a roughly rectangular hole 531. The hole 531 is slightly larger than the lead wire 25. The hole 531 penetrates from the tip surface of the lead wire protection portion 53 to the end surface opposite the tip surface. Therefore, when the cylindrical cover 5a is inserted into the inner circumference of the coil 2, the lead wire protection portion 53 and the lead wire 25 do not interfere with each other, and the lead wire 25 can penetrate the lead wire protection portion 53.

[0033] Fig. 4 is a perspective view of the cylindrical cover 5b. As shown in Fig. 4, the cylindrical cover 5b has a lead wire protection part 54. The lead wire protection part 54 is provided on the lower side surface of the annular surface protection part 52. The lead wire protection part 54 extends so as to protrude from the side surface of the annular surface protection part 52 in the lateral arrangement direction of the coils 2.

[0034] Fig. 5 is an enlarged view of the lead wire protection part 54. Fig. 6 is a perspective view of the lead wire protection part 54 with the side lead wire 26 attached thereto. The lead wire protection part 54 has a roughly U-shape when viewed from the lateral arrangement direction of the coils 2. The lead wire protection part 54 has a wall part 541, a long side part 542 and a short side part 543. The long side part 542 corresponds to a first extension part in the claims, and the short side part 543 corresponds to a second extension part in the claims.

[0035] Wall portion 541 extends perpendicular to the winding axis and perpendicular to the lateral arrangement direction of coil 2, i.e., in the up-down direction. Wall portion 541 is perpendicular to the winding axis and faces opposing surface 261 of side surface lead wire 26 located on the annular surface 24 side of coil 2. The length of wall portion 541 (the length between long side portion 542 and short side portion 543) need only be approximately the same as the height of side surface lead wire 26.

[0036] The long side portion 542 is connected to an upper end portion of the wall portion 541. The long side portion 542 extends from the wall portion 541 along the winding axis. The long side portion 542 has a tip surface 542a located opposite to the end surface connected to the wall portion 541. The long side portion 542 is disposed on the upper surface side of the side surface lead wire 26. In other words, a lower surface 542b of the long side portion 542 faces the upper surface of the side surface lead wire 26.

[0037] The short side portion 543 is connected to a lower end portion of the wall portion 541. The short side portion 543 extends from the wall portion 541 along the winding axis. The short side portion 543 has a tip surface 543a located opposite the end surface connected to the wall portion 541. The short side portion 543 is disposed on the lower surface side of the side surface lead 26. In other words, an upper surface 543b of the short side portion 543 faces the lower surface of the side surface lead 26.

[0038] There is a gap between the tip of the long side portion 542 and the tip of the short side portion 543, and the lead wire protection portion 54 has an opening 544. That is, the opening 544 is provided below the tip of the long side portion 542. The space surrounded by the wall portion 541, the long side portion 542, and the short side portion 543 becomes the storage space for the side lead wire 26.

[0039] FIG. 7 is an enlarged side view of the lead wire protection portion 54. As shown in FIG. 7, the extension length d1 of the long side portion 542 is longer than the extension length d2 of the short side portion 543. The extension length is the length from the base end portion connected to the wall portion 541 to the tip surface 542a, 543a of the long side portion 542 or the short side portion 543. The extension length of the short side portion 543 is at least longer than the length of the side lead wire 26 in the winding axis direction. In addition, the thickness t1 of the long side portion 542 is thicker than the thickness t2 of the short side portion 543. The thickness t1 of the long side portion 542 is preferably twice or more the thickness t2 of the short side portion 543. Note that the thickness here refers to the length in the up-down direction.

[0040] 1, the coil mold resin part 6 covers the coil 2, the upper cover 3, the annular cover 4, and the cylindrical cover 5. The coil mold resin part 6 integrates the coil 2, the upper cover 3, the annular cover 4, and the cylindrical cover 5. "Integrated" refers to a state in which the coil mold resin part 6 is continuous without any seams.

[0041] The coil molded resin part 6 is made of resin. Examples of the resin that constitutes the coil molded resin part 6 include epoxy resin, unsaturated polyester resin, urethane resin, BMC (Bulk Molding Compound), PPS (Polyphenylene Sulfide), and PBT (Polybutylene Terephthalate). In particular, it is desirable to use a resin with high thermal conductivity. By using a resin with high thermal conductivity, the heat of the coil 2 can be transferred to the outside.

[0042] The above molded coil 1 is used as a component of a reactor 9. The reactor 9 is an electromagnetic component that converts electric energy into magnetic energy and stores and releases the energy. FIG. 8 is a perspective view showing the overall configuration of the reactor 9. As shown in FIG. 8, the reactor 9 includes a core 7. The core 7 includes a magnetic body. The core 7 may be a powder magnetic core, a ferrite core, a laminated steel plate, a metal composite core, or the like. The metal composite core is a magnetic body formed by kneading magnetic powder and resin and hardening the resin.

[0043] The core 7 is made of two U-shaped core members, and is formed into a ring shape by joining the legs of the core 7 together. A spacer may be inserted between the legs of the core 7. The spacer may be made of a non-magnetic material, ceramic, non-metal, resin, carbon fiber, or a composite material of two or more of these materials, or gap paper. In this way, the spacer is used to provide a magnetic gap of a predetermined width, preventing a decrease in inductance of the reactor 9. Alternatively, an air gap may be provided instead of using a spacer.

[0044] The reactor 9 may further include a secondary molded resin part 8. The secondary molded resin part 8 covers the periphery of the molded coil 1 and the core 7. The secondary molded resin part 8 integrates the molded coil 1 and the core 7. The secondary molded resin part 8 is made of resin. The resin for the secondary molded resin part 8 may be the same type as that for the coil molded resin part 6. The secondary molded resin part 8 is formed by molding.

[0045] (action) Next, the mounting and molding of the cylindrical cover 5b will be described with reference to the drawings. First, a cylindrical cover mounting process is performed in which the cylindrical cover 5b is mounted on the wound coil 2. The cylindrical cover 5b has an inner peripheral surface protection part 51 inserted into the inner circumference of the coil 2. At this time, since the lead wire protection part 54 has an opening 544, the side lead wire 26 that is drawn along the lateral arrangement direction of the coil 2 can be accommodated in the accommodation space of the lead wire protection part 54 without interfering with the side lead wire 26. The cylindrical cover 5b is inserted into the inner circumference of the coil 2 until the annular surface protection part 52 abuts against the annular surface 24. After the cylindrical cover mounting process, the molding process is performed. The upper cover 3, the annular cover 4, and the cylindrical cover 5a are also mounted on the coil 2 in a process before or after the cylindrical cover mounting process.

[0046] In the molding process, the coil 2 with all the covers 3, 4, 5a, and 5b attached is placed in a metal mold, and resin is injected into the metal mold. The coil mold resin part 6 is formed by solidifying the resin.

[0047] 9 is a side view showing the state of coil 2 placed in die M in the molding process. Die M is pressed against lead wire protection portion 54. Die M has a surface that comes into contact with lead wire protection portion 54, which has a recessed step. The size of the step is approximately the same as the difference in length between long side portion 542 and short side portion 543. The step of die M is provided at the height of lower surface 542b of long side portion 542.

[0048] The die M has a leading end surface abutment portion M1, a bottom surface abutment portion M2, and a short side abutment portion M3. The leading end surface abutment portion M1 abuts against a leading end surface 542a of the long side portion 542. The bottom surface abutment portion M2 abuts against a part of the bottom surface 542b of the long side portion 542. The short side abutment portion M3 abuts against a leading end surface 543a of the short side portion 543. Although not shown in FIG. 9, the die M also abuts against the bottom surface of the short side portion 543 (the surface opposite to the top surface 543b of the short side portion 543).

[0049] With the contact portions M1 to M3 of the mold M in contact with the surfaces 542a, 542b, and 543a of the lead wire protection portion 54, the resin that forms the coil mold resin portion 6 is injected into the mold M. As shown by the black arrows in Fig. 9, the resin flows from above the lead wire protection portion 54 toward the exposed surface 22 of the coil 2. However, since the front end surface contact portion M1 of the mold M and the front end surface 542a of the long side portion 542 are in contact with each other, the path toward the exposed surface 22 of the coil 2 is blocked. Therefore, the resin is prevented from flowing into the exposed surface 22.

[0050] A reactor is manufactured from the molded coil 1 produced through the molding process. First, a core mounting process is performed in which a core is mounted on the molded coil 1. In the core mounting process, a U-shaped core member is inserted into the inner circumference of the coil 2 and joined with an adhesive or the like. Then, after the core mounting process, molding is performed using the resin of the secondary molded resin portion. This molding process integrates the molded coil 1 and the core, and a reactor is manufactured.

[0051] (effect) As described above, the molded coil 1 of this embodiment includes the coil 2, the cylindrical cover 5b that is inserted into the inner periphery of the coil 2 and covers the inner periphery of the coil 2, and the coil molded resin part 6 that integrates the coil 2 and the cylindrical cover 5b. The coil 2 has a side lead wire 26 that extends from a side surface of the coil 2 in a direction perpendicular to the side surface, and an exposed surface 22 that is not covered by the coil molded resin part 6 and is exposed. The side lead wire 26 is led out from the side surface on the exposed surface 22 side. The cylindrical cover 5b has a lead wire protection part 54 that protects the side lead wire 26. The lead wire protection portion 54 has a wall portion 541 facing an end face of the side lead wire 26 perpendicular to the winding axis, a long side portion 542 extending from one end of the wall portion 541 along the winding axis and positioned on the upper surface side of the side lead wire 26, and an opening 544 extending from the other end of the wall portion 541 along the winding axis and facing the wall portion 541.

[0052] By configuring the molded coil 1 in this manner, even when the coil 2 is provided with a side lead wire 26 extending in a direction perpendicular to the side of the coil 2, the side lead wire 26 can be inserted into the storage space of the lead wire protection portion 54 from the opening 544 without interference between the side lead wire 26 and the lead wire protection portion 54.

[0053] Furthermore, during molding, the tip surface 542a of the long side portion 542 comes into contact with the tip surface contact portion M1. Therefore, during molding, it is possible to prevent the resin from flowing into the exposed surface 22. In particular, since the long side portion 542 constituting the lead wire protection portion 54 is brought into contact with the mold M to cut the resin, there is no need to provide a separate configuration for cutting the resin, and the simple configuration can prevent the resin from flowing into the exposed surface 22.

[0054] The lead wire protection part 54 further has a short side part 543 which extends from the other end part of the wall part 541 along the winding axis and is disposed on the lower surface side of the side lead wire 26. As a result, the side lead wire 26 is supported by the short side part 543. Therefore, the side lead wire 26 is stabilized without being blown around by the injection pressure of the resin.

[0055] Furthermore, the tip surface 543a of the short side portion 543 abuts against the short side abutment portion M3 of the mold M. This distributes the pressing force of the mold applied to the lead wire protection portion 54 more than when only the long side portion 543 abuts against the mold M. This makes it possible to suppress deformation of the lead wire protection portion 54 and to suppress the occurrence of gaps between the tip surface 542a of the long side portion 542 and the tip surface abutment portion M1 and between the lower surface 542b and the lower surface abutment portion M2. This makes it possible to more accurately suppress the flow of resin into the exposed surface 22.

[0056] The metal mold also abuts against the underside of the short side portion 543. That is, not only the tip surface 543a but also the underside of the short side portion 543 abuts against the metal mold M. This makes it possible to suppress deformation of the short side portion 543, and also to determine the position, thereby preventing the lead wire protection portion 54 from being blown by the injection pressure of the resin. As a result, the side surface lead wire 26 accommodated in the accommodation space of the lead wire protection portion 54 can be positioned with high accuracy.

[0057] The extension length of the long side portion 542 is longer than the extension length of the short side portion 543. As a result, by providing one step in the mold M, the lower surface 542b of the long side portion 542 and the lower surface abutment portion M2 can be abutted against each other. For example, when the extension lengths of the long side portion 542 and the short side portion 543 are the same and the lower surface 542b of the long side portion 542 is to abut against the mold M for both the tip surface 542a of the long side portion and the tip surface 543a of the short side portion 543, it is necessary to provide at least two steps. This makes the mold more complicated and increases the manufacturing cost.

[0058] However, as in this embodiment, by making the extension length of the long side portion 542 longer than the extension length of the short side portion 543, one step can be used to bring the tip surface 542a of the long side portion 542 into contact with the tip surface abutment portion M1, the bottom surface 542b of the long side portion 542 into contact with the bottom surface abutment portion M2, and the tip surface 543a of the short side portion 543 into contact with the short side abutment portion M3. Therefore, it is possible to prevent the resin from flowing into the exposed surface 22 at low cost and with high accuracy.

[0059] The thickness of the long side portion 542 is thicker than the thickness of the short side portion 543. In other words, the long side portion 542 is thicker and more durable. This prevents the long side portion 542 from being deformed by the injection pressure of the resin, and thus prevents a decrease in the adhesion between the tip surface 542a of the long side portion 542 and the tip surface abutment portion M1.

[0060] (Other embodiments) In this specification, an embodiment of the present invention has been described, but this embodiment is presented as an example and is not intended to limit the scope of the invention. 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 invention and its equivalents described in the claims, as well as in the scope and gist of the invention.

[0061] In the above embodiment, the lead wire protection portion 54 has the short side portion 543, but the short side portion 543 may not be included. That is, the lead wire protection portion 54 may be configured only with the wall portion 541 and the long side portion 542, as shown in Fig. 10. That is, the lead wire protection portion 54 may have a shape resembling an inverted L when viewed from the lateral arrangement direction of the coils 2.

[0062] In the above embodiment, the thickness t1 of the long side portion 542 is set to be greater than the thickness t2 of the short side portion 543. However, as shown in Fig. 11, the thickness t3 of the long side portion 542 may be the same as the thickness t4 of the short side portion 543. However, since the long side portion 542 is subjected to the injection pressure of the resin, it is preferable that the long side portion 542 is thicker than the short side portion 543 in order to increase the strength.

[0063] In the above embodiment, the die M abuts on three surfaces with the lead wire protection portion 54, with the front end surface contact portion M1 and the bottom surface contact portion M2 abutting against the long side portion 542 and the short side abutting portion M3 abutting against the short side portion 543. However, as shown in Fig. 12, it is sufficient that at least the front end surface contact portion M1 abuts against the front end surface 542a of the long side portion 542. Even in this case, the front end surface contact portion M1 and the front end surface 542a of the long side portion 542 are in close contact with each other, so that the path of the resin toward the exposed surface 22 is blocked and it is possible to prevent the resin from flowing into the exposed surface 22. In addition, the structure of the die M can be further simplified, thereby reducing manufacturing costs.

[0064] In the above embodiment, the cylindrical cover 5 having the lead wire protection portion 54 that protects the side lead wire 26 has the inner circumferential surface protection portion 51, but instead of the inner circumferential surface protection portion 51, it is sufficient if the cover has at least one of the side surface protection portion 42 and the central extension portion 43, as in the annular cover 4. In this way, even when the side surface protection portion 42 or the central extension portion 43 is provided instead of the inner circumferential surface protection portion 51, the cover can be attached to the coil 2 without interference, and resin can be allowed to flow onto the exposed surface 22. [Explanation of symbols]

[0065] 1 Molded coil 2 Coil 21 Connecting Lines 22 Exposed surface 23, 24 Annular surface 25 Leader 26 Side leader line 261 Opposite Surface 3 Top cover 31 Top protection part 32 Connecting part 33 Protrusion 4 Circular cover 41 Annular surface protection part 411 Connection section 42 Side protection part 43 Central extension 5. Cylindrical cover 51 Inner peripheral surface protection part 52 Annular surface protection part 53 Leader line protection part 54 Leader wire protection section 541 Wall 542 Long side 542a Tip surface 542b Bottom side 543 Short side 543a Tip surface 543b Top side 544 Aperture 6 Coil mold resin part 7 cores 8 Secondary molded resin part 9. Reactor

Claims

1. A coil and A cover that covers an inner circumferential surface or a side surface of the coil; a coil mold resin portion that covers the coil and the cover; Equipped with The coil is an annular surface which is an end surface perpendicular to the winding axis; A side lead extending along a direction perpendicular to a side surface of the coil; an exposed surface that is not covered by the coil mold resin portion and is exposed; having The side lead line is led out from the exposed surface side of the annular surface, The cover is an annular surface protection portion for protecting the annular surface; A lead wire protection portion that protects the side lead wire; having The lead wire protection portion is a wall portion that is perpendicular to the winding axis and faces an end surface of the side-lead wire, the wall portion being located on the annular surface side from which the side-lead wire is drawn; a first extending portion extending from one end of the wall portion along the winding axis and facing an upper surface of the side lead; An opening which is a space below the first extension portion; having A molded coil characterized by:

2. the lead wire protection portion further includes a second extending portion extending from the other end of the wall portion along the winding axis and facing a lower surface of the side lead wire; The molded coil according to claim 1 .

3. An extension length of the first extension portion is longer than an extension length of the second extension portion; The molded coil according to claim 2 .

4. The thickness of the first extension portion is greater than the thickness of the second extension portion; The molded coil according to claim 2 .

5. A molded coil according to any one of claims 1 to 4; a core including a magnetic material and attached to the molded coil; To have A reactor characterized by the above.

6. A method for manufacturing a molded coil having side lead wires drawn in a direction perpendicular to a side surface of the coil, comprising the steps of: a cover mounting step of mounting a cover on the coil to cover an inner peripheral surface or a side surface of the coil; a molding step of placing the cover in a mold and injecting resin therein after the cover attachment step; Including, The coil is an annular surface which is an end surface perpendicular to the winding axis; an exposed surface that is not covered with the resin and is exposed; having The side lead line is led out from the exposed surface side of the annular surface, The cover is an annular surface protection portion for protecting the annular surface; a lead wire protection portion that covers the side lead wire; having The lead wire protection portion is a wall portion that is perpendicular to the winding axis and faces an end surface of the side-lead wire, the wall portion being located on the annular surface side from which the side-lead wire is drawn; a first extending portion extending from one end of the wall portion along the winding axis and facing an upper surface of the side lead; An opening which is a space below the first extension portion; having In the molding step, the die is in contact with a tip surface of the first extension portion; A method for manufacturing a molded coil, comprising the steps of:

7. A method for manufacturing a reactor, comprising the step of mounting a core on the molded coil according to claim 6.

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