JP2015130410A - Bobbin, reactor and method of manufacturing reactor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an easy-to-manufacture reactor where a part of a coil is exposed from a resin cover.SOLUTION: A reactor 10 includes a bobbin 20 made of resin and having a pair of flanges facing each other, a coil 3 wound around the bobbin 20 between the pair of flanges, a pair of plates 12a and 12b extending from one flange to the other flange, and abutting against the outer peripheral surface of the coil 3 between the pair of flanges, and a resin cover (not shown) covering one of two areas of the outer peripheral surface of the coil divide by the pair of plates. The pair of plates and the bobbin are coupled before molding the resin cover. The pair of plates define a cavity for molding the resin cover.

Description

  The present invention relates to a bobbin for winding a coil, a reactor using the bobbin, and a method for manufacturing the reactor. A reactor is a passive element using a coil, and is sometimes called an “inductor”.

  The reactor includes a magnetic core, a cylindrical bobbin through which the core is inserted, and a coil wound around the bobbin. Also, in many cases, the surface of the coil is often covered with a resin for the purpose of insulation and protection from physical contact with other devices.

  In a motor drive system of an electric vehicle including a hybrid vehicle, a reactor may be used for a circuit such as a voltage converter. A reactor for an electric vehicle generates a large amount of heat because a large current flows. In some cases, the entire coil is covered with a resin, but when the amount of heat generated is large, if the entire coil is covered with a resin, the heat of the coil is hardly diffused out of the resin. Therefore, a technique has been proposed in which a part of the coil is exposed from the resin cover and heat radiation from the coil is promoted at the exposed part (for example, Patent Document 1).

  In the technique of Patent Document 1, one surface of a metal block with high thermal conductivity is brought into contact with the exposed portion of the coil, the other surface of the metal block is brought into contact with the casing of the power converter, and the metal block is The heat of the coil is diffused through the casing.

JP 2011-249427 A

  As exemplified in Patent Document 1, in order to achieve both protection and cooling of the coil, it is preferable to cover a part of the coil with resin and expose the remaining part. Hereinafter, for the sake of explanation, a resin component covering the coil is referred to as a resin cover. The resin cover is often made by an injection molding method in order to improve the adhesion with the coil. Specifically, the coil and core assembly is placed in a mold, and a molten resin is injected to form a resin cover on a part of the outer peripheral surface of the coil. The mold is made of metal. On the other hand, since the coil is formed by winding a coil, the accuracy of the outer shape of the coil is not high. Therefore, there is a possibility that a gap is generated between the metal mold and the coil. If a gap is generated at the contact portion between the mold and the coil, the molten resin leaks, and the resin may protrude from the portion of the coil that should be exposed.

  The technology disclosed in the present specification provides a structure that facilitates manufacture of a reactor in which a part of a coil is exposed from a resin cover. Specifically, the technology disclosed in this specification provides a bobbin that can easily manufacture the above-described reactor, a reactor that employs such a bobbin, and a manufacturing method that uses the structure of such a reactor.

  A reactor targeted by the technology disclosed in this specification includes a bobbin having a pair of flanges, a coil, and a core. The coil is wound around a bobbin having a core inserted between a pair of flanges. And in the technique which this specification discloses, a pair of board | plate material is employ | adopted. Each of the pair of plate members extends from one flange of the bobbin to the other flange and is in contact with the outer peripheral surface of the coil between the pair of flanges. The outer peripheral surface of the coil is divided into two regions by this pair of plate members. Then, one of the divided areas is covered with a resin cover. Further, the reactor disclosed in the present specification employs a component in which a pair of plate members and a bobbin, a coil, and a core are connected in advance. In other words, the pair of plate members, the bobbin, the coil, and the core are assembled before the resin cover is molded.

  Since the resin cover is made by injection molding, it is necessary to place the assembly in a mold before molding the resin cover. As described above, when the outer peripheral surface of the coil is brought into direct contact with a metal mold, the injected resin may leak. Therefore, a pair of plate materials are brought into contact with the outer peripheral surface of the coil, and a mold is brought into contact with the plate materials. The pair of plate members seals between the mold and the outer peripheral surface of the coil, and defines a part of the cavity (space for injecting molten resin). However, in this case, the pair of plate members must be positioned at predetermined positions in the mold. Therefore, the reactor of the present specification adopts a structure in which a pair of plate members are connected to the bobbin in advance. By adopting such a structure, it is not necessary to separately arrange a pair of plate materials at predetermined positions before molding the resin cover. To repeat, the bobbin disclosed in the present specification has a pair of plate members connected to each other, and each of the pair of plate members is attached to one of the flanges along the outer peripheral surface of the coil when the coil is attached to the bobbin. It arrange | positions so that it may extend to the other flange. The pair of plate members are separated from the bobbin when the mold for resin injection molding is pressed to form the resin cover, abut against the outer peripheral surface of the coil, and bisect the outer peripheral surface of the coil. One of the two outer peripheral surfaces of the coil is an area covered with the resin cover.

  In addition, it is preferable that a pair of board | plate material is connected with the bobbin via the fracture | rupture planned part which fractures | ruptures when predetermined stress is added. Typically, the pair of plate members may be connected to any one of the flanges of the bobbin via the planned break portion. When such a structure is adopted, the reactor can be manufactured in the following process. That is, in the mold for injection molding the resin cover, the surface opposite to the coil contact surface of each of the pair of plate members in the assembly is brought into contact with the cavity surface of the mold. The pair of plate members are separated from the bobbin by the load received from the mold when they are brought into contact with each other. More specifically, the stress generated inside the planned fracture portion is increased by the load received from the mold, and the plate material is separated from the bobbin when the stress reaches a predetermined threshold value. Each of the pair of plate members separated from the bobbin is in contact with the side surface of the coil to define a cavity for molding the resin cover. Thereafter, resin is injected into the cavity to mold the resin cover. Thus, the operation of positioning the pair of plate members in the reactor manufacturing process is not necessary.

  In order to further improve the productivity, the pair of plate members may be connected to each other through the connection bar. And the relative position of a pair of board | plate material is decided by such a structure.

  Further, in one typical example of the structure of the entire reactor, the bobbin has two parallel cylindrical portions, and the first and second coils are wound around each of the two cylindrical portions. . The reactor having such an overall structure includes first and second plate members corresponding to the respective coils, and a third plate member between the first and second coils. It is preferable to adopt a structure in which the second and third plate members are connected together at their end portions via a connecting bar. The third plate member seals the gap between the first and second coils. In that case, the outer peripheral surfaces of the first and second coils are each divided into two regions by a total of three plate members.

  According to the technology disclosed in this specification, it becomes easy to manufacture a reactor in which a part of a coil is exposed from a resin cover. Details and further improvements of the technology disclosed in this specification will be described in the following “DETAILED DESCRIPTION”.

It is a coil assembly disassembled perspective view of the reactor of an Example (resin cover not shown). It is the perspective view which looked at the bobbin main body from diagonally downward. It is a disassembled perspective view of a coil assembly (state which inserted the cylindrical part of the bobbin in the coil). It is a perspective view of a coil assembly. It is sectional drawing of the coil assembly installed in the metal mold | die (equivalent to the VV cross section of FIG. 4). It is a perspective view of a reactor. It is a perspective view of the modification of a bobbin main body.

  The reactor is used, for example, in a voltage converter that boosts the voltage of a battery in a drive system of an electric vehicle. An electric vehicle driving motor can output tens of kilowatts, and the current flowing from the battery is tens of amperes. Since such a large current flows through the reactor, a rectangular wire having a small internal resistance is used as the winding. In addition, since the reactor generates a large amount of heat, it is used as a set with a cooler.

  A reactor according to an embodiment will be described with reference to the drawings. FIG. 1 shows an exploded perspective view of the reactor 10. However, FIG. 1 is an exploded perspective view of the reactor before the resin cover is mounted. Hereinafter, the reactor before mounting the resin cover is referred to as a coil assembly 10a. In the following, for convenience of explanation, the positive direction of the Z-axis of the coordinate system displayed in the figure is referred to as “upper”, and the negative direction of the Z-axis is referred to as “lower”.

  In the coil assembly 10a (reactor 10), a resin bobbin 20 is attached to a magnetic core 30 (30a, 30b), and a rectangular wire is wound around the bobbin 20 edgewise. The reactor 10 includes a pair of coils 3a and 3b. The two coils are electrically connected in series. Hereinafter, when a pair of coils 3a and 3b is shown without distinction, they are expressed as a coil 3. As will be described later, most of the coil 3, the core 30, and the bobbin 20 are covered with a resin cover (not shown in FIG. 1).

  The core 30 is divided into a pair of U-shaped core parts 30a and 30b, and an annular core is formed by facing them. A rectangular parallelepiped block core is disposed between the pair of core parts 30a and 30b, but the illustration thereof is omitted in FIG. The pair of U-shaped core parts 30a and 30b (and block cores) are collectively referred to as a core 30. The bobbin 20 includes a bobbin main body 22 and a flange part 21. Both the bobbin main body 22 and the flange part 21 are made of resin. The bobbin main body 22 has a structure in which a pair of cylindrical portions 23 are connected by a flange portion 25 so that they are parallel to each other. The block core described above is accommodated in the cylindrical portion 23. The cylindrical portion 23 has a rectangular cross section, and a protrusion 24 is provided on each of its four surfaces (a part of the protrusions is omitted in FIG. 1). The ridge 24 extends along the axial direction of the cylindrical portion 23 (X-axis direction in the figure). As will be described in detail later, three plate members 12a-12c are connected to the flange portion 25. The three plate members 12 a to 12 c extend along the axial direction of the cylindrical portion 23. The three plate members 12a-12c are made of the same resin as the bobbin 20. Further, the flange portion 25 is provided with a slit 25a through which the lead portion 31 (coil lead wire) of the coil 3 passes.

  The U-shaped leg portion of one core part 30 a is inserted into the tube portion 23 from the flange portion 25 side of the bobbin main body 22. In addition, a block core is disposed in the center of the inside of the cylindrical portion 23, and the front end surface of the core part 30a faces the block core. On the outside of each of the pair of tube portions 23, coils 3a and 3b in which a flat wire is wound edgewise are arranged. As well shown in FIG. 1, the pair of coils 3a and 3b is formed by a single rectangular wire, and the coil 3 is wound in the same direction as the pair of coils 3a and 3b. Are arranged in parallel. Since the flat wire has high rigidity, the shape of the single coil can be maintained. After inserting the bobbin main body 22 into the coil 3, the flange part 21 is attached from the opposite side of the coil, and finally the core parts 30a and 30b are inserted from the respective end portions of the bobbin 20 into the cylindrical part 23 to complete the coil assembly 10a. To do. The flange part 21 is provided with a hole 21a through which the cylindrical portion 23 is passed.

  FIG. 2 is a perspective view of the bobbin main body 22 as viewed obliquely from below. However, in FIG. 2, the holes for passing the U-shaped core part 30a and the cylindrical portion 23 are not shown. FIG. 3 shows the coil assembly 10 a in a state where the coil 3 is inserted through the cylindrical portion 23 of the bobbin 20. As described above, the three plate members 12 a, 12 b, and 12 c that extend along the axial direction of the cylindrical portion 23 are connected to the bobbin main body 22. As shown in FIG. 2, the plate members 12 a and 12 b are connected to the flange portion 25 of the bobbin main body 22 via the connecting bar 14, and the plate member 12 c is connected to the plate members 12 a and 12 b via the connecting bar 15. Yes. That is, the three plate members 12 a to 12 c are connected to each other by the connecting bar 15.

  The connecting bar 14 is provided with a fragile portion having a low breaking strength due to the notch. The fragile portion is referred to as a planned fracture portion 14a. As will be described in detail later, when the coil assembly 10a is placed in a mold and the plate members 12a and 12b are pressed by the inner surface of the mold, the planned break portion 14a is broken by the load at that time, and the plate members 12a and 12b are flanged. The resin is separated from the portion 25 (bobbin 20), and a resin is injection molded around the coil 3 leaving a part.

  As shown in FIG. 3, when the coil 3 is inserted through the cylindrical portion 23, the side surface of each plate material faces the peripheral surface of the coil 3. The side surface 13a of the plate material 12a and the side surface 13d of the plate material 12c are opposed to the outer peripheral surface of the coil 3a, and the side surface 13b of the plate material 12b and the other side surface 13c are opposed to the outer peripheral surface of the coil 3b. In other words, the pair of plate members 12a and 12c are opposed to the outer peripheral surface of the coil 3a, and the pair of plate members 12b and 12c are opposed to the outer peripheral surface of the coil 3b. The plate 12c faces the coil 3a and the coil 3b in common. That is, the bobbin 20 has two parallel cylindrical portions 23, and the first coil 3a and the second coil 3b wound around each of the two cylindrical portions 23, and the respective coils 3a, 3b is provided with a first and second pair of plate members (plate members 12a and 12c, and plate members 12b and 12c), and the plate members 12a, 12b and 12c are connected to each other by the connecting bar 15 at one end thereof. It is connected to. Further, the plate members 12a and 12b are connected to the bobbin main body 22 (bobbin 20) by a connecting bar 14 having a planned fracture portion 14a.

  When viewed from the axial direction, the coil 3 has a rectangular shape with rounded corners, and the side surfaces 13a-13d of the plate members 12a-12c face the curved corners of the coil 3. The side surfaces 13 a-13 d facing the outer peripheral surface of the coil 3 are curved along the curved corners of the coil 3.

  As shown in FIG. 2, the corner portions 25b at both ends of the lower edge of the flange portion 25 (edge in the negative direction of the Z axis in the figure) also follow the curved side surfaces 13a and 13b of the plate materials 12a and 12b. Is curved. Further, a notch 25d is provided in the center of the lower end of the flange portion 25 so that the plate material 12c passes, and the corner portion 25c where the side surface of the notch 25d and the lower edge of the flange portion 25 merge is also curved of the plate material 12c. Curved along the side surfaces 13c and 13d.

  The shape of the lower part of the flange part 21 which makes a pair with the flange part 25 is the same as that of the flange part 25 (see FIG. 1). That is, the corners 21b at both ends of the lower edge of the flange part 21 are also curved along the curved side surfaces 13a and 13b of the plate members 12a and 12b. Further, a notch 21d is provided in the center of the lower edge of the flange part 21 so that the plate material 12c passes, and a corner 21c where the side surface of the notch 21d and the lower edge of the flange part 21 merge is also formed on the plate material 12c. It is curved along the curved side surfaces 13c and 13d.

  When the cylindrical part 23 is inserted into the pair of coils 3a and 3b and the flange part 21 is fitted to the tip of the cylindrical part 23 by the above-described structure of the plate member 12a-12c, the lower edge of the flange part 25 and the lower edge of the flange part 21. It becomes as follows. That is, a pair of plate members 12a, 12c (12b, 12c) extends from one flange (flange portion 25) to the other flange (flange part 21) with respect to one coil 3a (3b), and a pair of flanges Facing the outer peripheral surface of the coil 3a (3b). As will be described in detail later, when the coil assembly 10a is placed in a mold for injection molding of a resin cover (described later), the side surfaces 13a-13d of the plate members 12a-12c are formed with a pair of flanges (a flange portion 25 and a flange part). 21) is closely attached to the outer peripheral surface of the coils 3a and 3b.

  FIG. 4 is a perspective view of the coil assembly 10a in which the bobbin 20, the core 30, and the coil 3 are assembled. A state in which the plate member 12b is opposed to the outer peripheral surface of the coil 3a between the pair of flanges is depicted. Although not visible in FIG. 4, the same applies to the plate members 12b and 12c. Although the lower surface 3c of the coil 3b is visible in FIG. 4, this portion is exposed even after the resin cover molding described later.

  The coil assembly 10a is placed in a mold and resin is injected from a portion of the coil 3 above the plate materials 12a-12c, and a resin cover is formed into the coil assembly 10a. Next, a method for forming the resin cover will be described.

  FIG. 5 is a cross-sectional view when the coil assembly 10 a is set in the mold 40. The cross section of the coil assembly 10a in FIG. 5 corresponds to the cross section taken along the line V-V in FIG. In other words, the cross-sectional view of FIG. 5 corresponds to a cross section that crosses the axis of the coil. In FIG. 5, the code | symbol 19 has shown the rectangular parallelepiped block core.

  The mold 40 includes a lower mold 41, an upper mold 42, and slide molds 42a, 42b, 45a, and 45b. The coil assembly 10a is placed on the lower mold 41, and the upper mold 42 is covered from above. Part of the cavity surface on the side of the upper mold 42 is a slide mold 42a, 42b, and the slide molds 42a, 42b slide in the Y-axis direction and come into contact with the back surfaces of the plate members 12a, 12b. The slide dies 42 a and 42 b press the plate members 12 a and 12 b against the outer peripheral surface of the coil 3. The coil 3 is obtained by winding a rectangular wire with high rigidity edgewise, and the position of the side surface of the rectangular wire of each pitch is slightly shifted, so that the surface accuracy of the outer peripheral surface of the coil is not high. However, the slide molds 42a and 42b press the resin plate members 12a and 12b against the outer peripheral surface of the coil, so that the plate members 12a and 12b align the side surfaces of the rectangular wires that constitute the outer peripheral surface of the coil, and the two are in close contact with each other without a gap. To do. The same applies to the plate 12c as will be described later.

  Before the slide molds 42 a and 42 b are pressed, the plate members 12 a and 12 b are separated from the outer peripheral surface of the coil 3. However, since the plate members 12 a, 12 b, and 12 c are connected to the bobbin 20, the positions of the plate members 12 a, 12 b, and 12 c are maintained without other support members when placed in the mold 40. Although the plate member 12c is not directly connected to the bobbin 20, since the plate member 12c is connected to the bobbin 20 via the connecting bar 15, the plate member 12c is also kept in its position.

  When pressed by the slide molds 45 a and 45 b, the connecting bar 14 is deformed, and the plate members 12 a and 12 b are in close contact with the outer peripheral surface of the coil 3. At this time, the stress generated inside the planned fracture portion 14a increases due to the deformation of the connecting bar 14, and the planned fracture portion 14a breaks when the stress exceeds a predetermined threshold. The plate members 12a and 12b, which are free from the bobbin 20 due to the breakage portion 14a being broken, are in close contact with the outer peripheral surface of the coil 3.

  Further, a protrusion 41a is provided at the center of the lower die 41 so as to face the plate member 12c. The protrusion 41a is provided so as to extend along the plate material 12c. When the coil assembly 10 a is placed on the lower mold 41, the protrusion 41 a pushes up the plate material 12 c and presses the side surface of the plate material 12 c against the outer peripheral surface of the coil 3. When the protrusion 41a presses the resin plate 12c against the outer peripheral surface of the coil, the plate 12c aligns the side surfaces of the rectangular wires constituting the outer peripheral surface of the coil, and the two are in close contact with each other without a gap.

  When the pair of plate members 12a and 12c are in close contact with the coil 3a, the outer peripheral surface of the coil 3a is divided into two regions. One is an area above the plate members 12a and 12c, and this area faces a cavity CA described later. The other is an area below the plate members 12a and 12c. This region is referred to as a coil lower surface 3c. The coil lower surface 3c faces a space SP2 described later. The same applies to the coil 3b and the pair of plate members 12b and 12c, and the pair of plate members 12b and 12c divides the outer peripheral surface of the coil 3b into two regions.

  When the slide molds 42a, 42b and 45a, 45b press the plate members 12a, 12b, the corner portion 25b of the lower edge of the flange portion 25 also comes into close contact with the side surfaces 13a, 13b of the plate members 12a, 12b. Further, when the protrusion 41a presses the plate member 12c upward, the corner portion 25c of the notch 25d of the flange portion 25 also comes into close contact with the side surfaces 13c and 13d of the plate member 12c. The same applies to the flange part 21. The flange portion 25 and the flange part 21 are simply referred to as a flange. The plate materials 12a-12c are in close contact with the outer peripheral surface of the coil and the lower edge of the flange.

  When the slide dies 42a, 42b and 45a, 45b bring the plate members 12a-12c into close contact with the coil and flange lower edges, a cavity CA is formed above the plate members 12a (12b, 12c). Molten resin is injected from the gate 44 into the cavity CA. When the molten resin is solidified, a resin cover having the shape of the cavity CA is formed on the coil assembly 10a including the coil outer peripheral surface.

  As described above, the plate members 12a to 12c are in close contact with the outer peripheral surface of the coil and prevent the molten resin injected into the cavity CA from leaking into the space SP2. In other words, the coil lower surface 3c in the space SP2 is reliably isolated from the cavity CA and is not covered with the molten resin. Since the plate members 12a-12c and the flange are also in close contact, the resin does not leak from the boundary of the flange.

  In addition, although space SP1 exists also between the outer side of the cylinder part 23 of the bobbin inside the coil 3, and the coil 3, molten resin flows also here. When the molten resin is solidified, the coil 3 and the cylindrical portion 23 are in close contact with each other, and the coil 3 is fixed to the cylindrical portion 23.

  FIG. 6 shows a perspective view of the completed reactor 10. The coil 3 is covered with the resin cover 16 above the plate material 12b, but the coil lower surface 3c below the plate material 12b is exposed. In addition, the fracture | rupture scheduled part 14a of the connection bar 14 is fractured | ruptured when the slide type | molds 45a and 45b press the board | plate material 12a (12b). FIG. 6 shows that the planned fracture portion 14a is broken.

  Points to be noted regarding the technology of the embodiment will be described. The pair of plate members 12a and 12c for the coil 3a and the pair of plate members 12b and 12c for the coil 3b are arranged between the flanges of the bobbin 20 inside the mold 40 before the resin cover 16 is injection molded. It abuts against the surface and the inner surface of the mold. This plate material serves as a boundary between an area that is later covered with the resin cover 16 and an exposed area (coil lower surface 3c) on the outer peripheral surface of the coil. In other words, the plate members 12a to 12c define a cavity CA for injection molding the resin cover 16.

  When the resin cover 16 is injection-molded, the outer peripheral surface of one of the coils is filled with the plate material as a boundary, and the molten resin does not ooze out to the coil lower surface 3c. That is, the plate members 12a-12c contribute to reliably exposing the planned exposed surface (coil lower surface 3c). The plate members 12a-12c are connected to the flange portion 25 (bobbin 20) in advance before the resin cover 16 is injection molded. Therefore, there is no need to support the plate members 12a-12c with other members inside the mold 40. Since it is not necessary to arrange an additional member in the mold for supporting the plate material, the manufacturing process is not complicated.

  Further, the plate member 12a (12b) is connected to the bobbin by a connecting bar 14 provided with a planned breaking portion 14a having a breaking strength lower than that of other portions. By providing the planned fracture portion 14a, the plate 12a (12b) is reliably separated from the bobbin in the mold. The plate members 12a (12b and 12c) that are free from the bobbin are in close contact with the outer peripheral surface of the coil.

  The plate members 12a-12c and the bobbin main body 22 are both made of resin. If the plate members 12a-12c are formed integrally with the bobbin main body 22, the bobbin connected to the plate members can be easily manufactured.

  The plate material 12a (12b) of the embodiment is connected to the flange portion 25 (bobbin 20) by the connecting bar 14. If the connection strength or bending rigidity is insufficient with only the connection bar 14, the plate member 12a (12b) may be connected to the bobbin 20 at a plurality of locations using an auxiliary connection bar. In FIG. 7, the perspective view of the bobbin main body 122 (bobbin) of a modification is shown. In this modification, the plate member 12a (12b) is connected to the bobbin by the connecting bar 14 and the auxiliary connecting bar 114. The plate member 12c is connected to the plate members 12a and 12b by the connecting bar 15 similarly to the bobbin in the above-described embodiment. In addition to the embodiment of FIG. 7, the plate member 12 c may be directly connected to the bobbin without using the connecting bar 15.

  Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above. The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or the drawings can achieve a plurality of objects at the same time, and has technical usefulness by achieving one of the objects.

3, 3a, 3b: Coil 3c: Coil lower surface 5: Core block 10: Reactor 10a: Coil assemblies 12a, 12b, 12c: Plate members 13a, 13b, 13c, 13d: Plate side surfaces 14, 15: Connection bar 14a: Planned breakage Part 16: Resin cover 20: Bobbin 21: Flange part 21b: Lower edge both ends 21c of the flange part: Corner part 21d of the lower edge notch of the flange part: Notch 22, 122: Bobbin main body 23: Tube part 24: Rib 25: Flange part 25b: Lower edge both ends 25c of flange part: Corner part 25d of lower edge notch of flange part: Notch 30: Core 30a, 30b: Core part 40: Mold 41: Lower mold 41a: Projection 42: Upper mold 42a 42b, 45a, 45b: slide mold 44: gate CA: cavity SP1, SP2: space

Claims (7)

A resin bobbin having a pair of opposed flanges,
A pair of plate members are connected to the bobbin, and each of the pair of plate members extends from one flange to the other flange along the outer peripheral surface of the coil when the coil is attached to the bobbin. Bobbins characterized by being arranged in A bobbin according to claim 1;
A coil wound around the bobbin between the pair of flanges;
A resin cover covering one of the two regions of the outer peripheral surface of the coil divided by the pair of plate members;
With
The reactor, wherein the pair of plate members are separated from the bobbin when the resin cover is molded and abut against the outer peripheral surface of the coil.   The reactor according to claim 2, wherein the pair of plate members are connected to the bobbin via a planned fracture portion that fractures when a predetermined stress is applied.   The reactor according to claim 2, wherein the pair of plate members are coupled to each other at an end portion via a coupling bar. The bobbin has two parallel cylindrical portions,
First and second coils wound around each of the two cylindrical portions;
A pair of first and second plate members in contact with the outer peripheral surface of each of the coils;
A third plate between the first and second coils;
With
The reactor according to claim 3, wherein the first to third plate members are connected together at one end thereof via a connecting bar.   The reactor according to any one of claims 2 to 5, wherein the pair of plate members are connected to one of the pair of flanges. It is the manufacturing method of the reactor of any one of Claim 2 to 6,
Due to the load received from the mold when the surface opposite to the coil contact surface of each of the pair of plate materials contacts the cavity surface of the mold in the mold for injection molding the resin cover A method of manufacturing a reactor, wherein the pair of plate members are separated from the bobbin, each of the pair of separated plate members is in contact with a side surface of the coil, and a cavity for molding the resin cover is defined.

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