JP7509620B2 - Reactor - Google Patents

Description

The present invention relates to a reactor.

Reactors are used in a variety of applications, including office equipment, solar power generation systems, automobiles, and uninterruptible power supplies. Reactors are used, for example, in filters that prevent harmonic currents from flowing into output systems, and in voltage step-up and step-down converters that raise and lower voltages. A known type of reactor has a core that is covered with a resin material and a coil attached to the outer periphery of the resin material in order to insulate the core from the coil.

There are so-called horizontal reactors in which the direction of the coil winding axis is parallel to the installation surface. In horizontal reactors, fixing parts provided at the four corners of the resin member covering the core and four fixing parts provided on the fixing object such as a case are fixed with fixing devices such as screws. The resin member is also provided with terminal fastening parts that support terminals for electrical connection between the coil and the outside. The terminals are configured at the ends of bus bars welded to the ends of the coil, and are fastened to external terminals with fasteners such as nuts.

Japanese Patent No. 6628156

In such horizontally placed reactors, the fixing part and the terminal fastening part must be located in a position that protrudes outward from the outer edge of the core in a plan view. This is because if the fixing part is located on the inside, it will be in a position that overlaps with the core, making it impossible to fix it to the case. Furthermore, if the terminal fastening part is located on the inside, the core that exists below the supporting terminal gets in the way, making it impossible to perform insert molding to integrate it with the terminal. If the terminal fastening part is formed on the inside, it must be formed in a position away from the fixing part located on the outside of the core, with a space below, which results in insufficient strength against vibration, etc.

The present invention was made to solve the above problems, and its purpose is to provide a small reactor that can ensure the strength of the terminal fastening parts.

The reactor of the present invention has a core having multiple legs and a pair of connecting parts connecting the ends of the multiple legs, coils attached to both ends of the legs in the arrangement direction of the multiple legs, and a resin member covering the connecting parts. The resin member covering one of the connecting parts is provided with terminal fastening parts at both ends sandwiching the connecting part, which are provided in positions where the coil overlaps with the winding axis direction, support terminals for electrical connection between the coil and the outside, and are fastened with a fastener with an axis parallel to the winding axis, and a fixing part provided in a position where the coil does not overlap with the winding axis direction and adjacent to the terminal fastening parts, and is fastened with a fixture with an axis parallel to the winding axis.

According to the present invention, the terminal fastening portion is provided at a position where the coil and the winding axis overlap, and the fixing portion is provided at a position adjacent to the terminal fastening portion, thereby ensuring the strength of the terminal fastening portion while achieving miniaturization.

1 is a perspective view showing an overall configuration of a reactor according to an embodiment; FIG. 2 is an exploded perspective view of the reactor according to the embodiment. FIG. 2 is a plan view of the reactor according to the embodiment. 4 is a cross-sectional view taken along the line AA in FIG. 3. FIG. 2 is a front view of the reactor according to the embodiment.

The reactor according to this embodiment will be described with reference to the drawings. FIG. 1 is a perspective view showing the overall configuration of the reactor 10 according to this embodiment, and FIG. 2 is an exploded perspective view. FIG. 3 is a plan view of the reactor 10, FIG. 4 is a cross-sectional view, and FIG. 5 is a front view.

The reactor 10 is an electromagnetic component that converts electrical energy into magnetic energy and stores and releases it, and is used for stepping up and down voltages, etc. The reactor 10 of this embodiment has an annular core 2 (see Figures 2 and 4) to which a pair of coils 31, 32 are attached. Such a reactor 10 is used as a main component of a boost circuit, for example, in the drive systems of hybrid and electric vehicles.

When the reactor 10 of this embodiment is arranged so that the winding axis of the coil 3 is vertical, the winding axis direction is the up-down direction. In the following description, in the winding axis direction, the first resin member 41 side of the reactor 10 is called the top, and the opposite second resin member 42 side is called the bottom. Also, in this embodiment, the winding axis direction is considered to be vertical, and the reactor 10 is a vertical type reactor that is installed by being inserted vertically into a case or installation location. However, these directions are expressions to show the positional relationship of each component of the reactor 10, and do not limit the positional relationship and direction in which the reactor 10 is installed on the installation target.

[composition]
As shown in FIGS. 1 and 2 , the reactor 10 includes a core 2 , coils 31 and 32 , a resin member 4 , a terminal fastening portion 5 , and a fixed portion 6 .

(core)
The core 2 is a member molded from a magnetic material. As shown in Fig. 2 and Fig. 4, the core 2 of this embodiment is formed by combining partial cores each having a rectangular parallelepiped shape into a rectangular ring and bonding them with an adhesive. Each partial core has a pair of legs 21 and a pair of connecting parts 22 that connect the ends of the legs 21.

The pair of legs 21 are arranged side by side so as to be parallel to each other, and coils 31 and 32, which will be described later, are wound around each of them. The pair of connecting parts 22 are yoke parts that serve as paths for the magnetic flux generated in the legs 21 by the coils 31 and 32, and form a magnetic circuit together with the legs 21. For example, a powder magnetic core, ferrite, laminated steel plate, metal composite core (MC core), etc. can be used as the core 2.

(coil)
The coils 31 and 32 are members in which conductive wire is wound into a cylindrical shape. In this embodiment, the coils 31 and 32 are edgewise coils of rectangular copper wire with an insulating coating. However, the wire and winding method of the coils 31 and 32 are not limited to this, and may be other forms. The coils 31 and 32 are arranged side by side with a gap between them so that the winding axes are parallel to each other, and are electrically connected by a connecting portion at one end. At the other end of the coils 31 and 32, a lead wire 3a is provided that is drawn out from the winding portion for electrical connection to the outside.

The pair of lead wires 3a are pulled out in opposite directions in a direction perpendicular to the winding axis, and are then bent upward. The two coils 31, 32 are attached around the two legs 21. In other words, the coils 31, 32 are wound around the legs 21 located at both ends in the arrangement direction among the multiple legs 21. Therefore, the outer circumferences of the coils 31, 32 protrude outward from both ends in the arrangement direction beyond the legs 21.

(Resin member)
The resin member 4 is a member made of resin that covers the core 2. Examples of types of resin include epoxy resin, unsaturated polyester resin, urethane resin, BMC (Bulk Molding Compound), PPS (Polyphenyl Sulfide), and PBT (Polybutylene Terephthalate).

As shown in FIG. 2, the resin member 4 of this embodiment has a divided structure of a first resin member 41 and a second resin member 42. The first resin member 41 has a portion that entirely covers one of the connecting portions 22, and a cylindrical portion into which the ends of the two legs 21 are inserted. The second resin member 42 has a portion that entirely covers the other connecting portion 22, and a cylindrical portion that covers most of the two legs 21.

The ends of the legs 21 exposed from the second resin member 42 are inserted into the cylindrical portion of the first resin member 41 and bonded to the internal connecting portion 22, and the cylindrical portions of the first resin member 41 and the second resin member 42 are mated to cover the entire core 2. The first resin member 41 and the connecting portion 22, and the second resin member 42 and the connecting portion 22 are each formed by molding.

(Terminal fastening part)
The terminal fastening portions 5 are provided at both ends of the first resin member 41 that sandwich the connecting portion 22 at positions where overlap with the coils 31, 32 occurs in the winding axis direction. The position where overlap occurs in the winding axis direction means that at least a part of the terminal fastening portions 5 is within a projected range of the coils 31, 32 in the winding axis direction, and the terminal fastening portions 5 may or may not be in contact with the end faces (top faces) of the coils 31, 32. More specifically, first, in a plan view, the first resin member 41 that covers the rectangular parallelepiped connecting portion 22 has a longitudinal direction in which the legs 21 are arranged and a direction perpendicular to this is a lateral direction.

The coils 31 and 32 protrude downward from the short side surface 41a of the first resin member 41. Therefore, a space S exists above the protruding portions of the coils 31 and 32 (the area surrounded by the dotted line in FIG. 4). A bulging portion 41b protruding from the side surface 41a is provided at a position overlapping this space S. However, the bulging portion 41b is not in contact with the coils 31 and 32. The bulging portion 41b is provided at an offset position extending from the center of the side surface 41a to one end in a plan view, as shown in FIG. 3.

The terminal fastening portion 5 is provided on the bulge portion 41b. The terminal fastening portion 5 is provided at a position where the coils 31, 32 overlap in the winding axis direction, and is provided in the center of the side surface 41a in a plan view. The terminal fastening portion 5 supports the terminal 71. The terminal 71 is a rounded portion of one end of the busbar 7, and has an attachment hole 71a formed in the center. The terminal fastening portion 5 supports the terminal 71 in a direction perpendicular to the winding axis.

The bus bar 7, which has the above-mentioned terminal 71 at one end, is a plate-shaped conductive member made of copper, aluminum, or the like. The bus bar 7 is bent so as to be embedded in the resin of the bulge 41b from the vicinity of the exposed terminal 71, and is further bent so as to form an approximately U-shape parallel to the side surface 41a, with the other end exposed from the lower part of the side surface of the bulge 41b. The other end thus exposed becomes the end portion 72 that is connected to the lead wire 3a of the coils 31, 32 by welding or the like.

A nut 51 is embedded in the terminal fastening portion 5 so as to be continuous with the mounting hole 71a of the terminal 71. The mounting hole 71a and the nut 51 are coaxial in a direction parallel to the winding shaft. Therefore, a fastener such as a bolt is fastened to the nut 51 with an axis parallel to the winding shaft.

(Fixed part)
The fixed portion 6 is also provided in the bulge 41b. The fixed portion 6 is provided at a position adjacent to the terminal fastening portion 5, where there is no overlap with the coils 31, 32 in the winding axis direction. Adjacent here means close to the terminal fastening portion 5 without any intervening material or member other than the resin. A through hole is formed in the fixed portion 6, and a cylindrical collar 61 is embedded in this through hole. The axis of the collar 61 is parallel to the winding axis. For this reason, a fastener such as a bolt is inserted into the collar 61 with its axis parallel to the winding axis, and the collar 61 is fixed to a screw hole in a case or the like.

The connection portion C between the lead wire 3a of the coils 31 and 32 and the end portion 72 of the busbar 7 is adjacent to the terminal fastening portion 5 in a direction different from that of the fixed portion 6. In other words, in a plan view, the terminal fastening portion 5 is sandwiched between the fixed portion 6 and the connection portion C, with the fixed portion 6 located in one area and the terminal fastening portion 5 in the other area.

The terminal fastening portion 5 and fixing portion 6 as described above are provided on the two short-side side surfaces 41a of the first resin member 41 at positions that are point-symmetrical in a planar view. As a result, the fixing portions 6 are arranged at diagonal positions in a planar view. The pair of fixing portions 6 provided on the two side surfaces 41a in this manner fixes the reactor 10 to a case or the like. The terminal fastening portion 5, fixing portion 6, and connection portion C are approximately within the width of the short side in a planar view.

The fixing part 6 has a protrusion that protrudes outward in the short direction, but this is a slight protrusion for positioning when mounting to a case, etc., and there is no protrusion at all on the longitudinal side of the part where the connecting part 22 is embedded. Therefore, even when other parts are placed adjacent to the main body part consisting of the core 2 and coils 31, 32 of the reactor 10, the spacing between them can be shortened to save installation space.

The terminal fastening portion 5 is provided at a position where it overlaps with the coils 31 and 32 in the winding axis direction, utilizing the above-mentioned space S, so that the longitudinal length can be made shorter than when the terminal fastening portion 5 is provided outside the outer edge of the coils 31 and 32. The fixing portion 6 is also provided adjacent to the terminal fastening portion 5, so that the distance between the coils 31 and 32 can be reduced, and the reactor 10 as a whole can be made smaller in the longitudinal direction.

In addition, the busbar 7 including the terminal 71, the nut 51, and the collar 61 are located in positions where they do not overlap with the connecting portion 22 of the core 2 in the winding axis direction, and can be formed by insert molding. In other words, the terminal fastening portion 5 and the fixing portion 6 can be integrally formed with the connecting portion 22 from resin. In the first resin member 41, the terminal fastening portion 5 and the fixing portion 6 are formed in one piece without any seams. In other words, the terminal fastening portion 5 and the fixing portion 6 are continuous with each other through the resin.

In addition, because the terminal fastening portion 5 utilizes the above-mentioned space S, as shown in FIG. 5, it is possible to ensure a thickness equal to or greater than the vertical length T of the side surface 41a, resulting in high vibration resistance. In this embodiment, the terminal fastening portion 5 protrudes from the top surface, making it even thicker than the height of the side surface 41a.

[effect]
(1) The reactor 10 of this embodiment includes a core 2 having a plurality of legs 21 and a pair of connecting portions 22 that connect the ends of the plurality of legs 21, coils 31, 32 respectively attached to the legs 21 at both ends in the arrangement direction of the plurality of legs 21, and a resin member 4 that covers the connecting portions 22.

The first resin member 41 that covers one of the connecting parts 22 is provided with terminal fastening parts 5 at both ends of the connecting part 22, at positions where the coils 31, 32 overlap in the winding axis direction, and support terminals 71 for electrically connecting the coils 31, 32 to the outside. The terminal fastening parts 5 are fastened with a fastener along an axis parallel to the winding axis.

Furthermore, the first resin member 41 is provided with a fixing portion 6 that is provided adjacent to the terminal fastening portion 5 at a position where there is no overlap with the coils 31, 32 in the winding axis direction, and to which a fixing device is fixed with an axis parallel to the winding axis.

In this way, the terminal fastening portion 5 is provided at a position where it overlaps with the coils 31, 32 in the winding axis direction, so the space S can be effectively utilized to achieve miniaturization. In addition, by arranging the fixing portion 6 at a position adjacent to the terminal fastening portion 5, the strength of the terminal fastening portion 5 is improved compared to when the terminal fastening portion 5 is provided at a position away from the fixing portion 6, and the vibration resistance of the terminal 71 is increased, and bending, etc., when the fastener is fastened can be prevented.

And because it can be fixed to the case or the like in a position close to the core 2 and coils 31, 32, the vibration resistance strength of the reactor 10 as a whole can be increased. Furthermore, by providing terminal fastening parts 5 on both ends of the connecting part 22 and providing fixing parts 6 in positions adjacent to each of them, the fixing points are not biased to one part of the reactor 10, and stable fixing is possible.

(2) The coils 31, 32 have connection parts C between the lead wires 3a, which are the ends of the coils 31, 32, and the end 72 of the busbar 7, which includes the terminal 71. The connection parts C are arranged in a position adjacent to the fixed part 6 in a different direction relative to the terminal fastening part 5. Therefore, the fixed part 6 is arranged in one area across the terminal fastening part 5, and the connection parts C are arranged in the other area, so that heat is not easily transferred to the fixed part 6 when the connection parts C are connected by welding. Furthermore, the positions of the terminal fastening part 5, the fixed part 6, and the connection parts C can be concentrated in a narrow area, achieving an overall compact size.

(3) In the first resin member 41 that covers the connecting portion 22, the direction in which the legs 21 are arranged is the longitudinal direction, and the direction perpendicular to this is the transverse direction, and the terminal fastening portion 5 and the fixing portion 6 are provided on the side surface 41a, which is the surface in the transverse direction. This increases the distance between the pair of fixing portions 6, and further improves the vibration resistance of the entire reactor 10. In this embodiment, the fixing portions 6 are arranged diagonally in a plan view, so that the distance between the two fixing points can be further increased, enabling stable fixing. In addition, by concentrating the terminal fastening portions 5 and the fixing portions 6 on the side surface 41a in the transverse direction, the external shape is prevented from expanding outward in the longitudinal direction.

(4) The terminal fastening portion 5 and the fixing portion 6 are formed as a single piece without any seams. This allows for greater vibration resistance than when the terminal fastening portion 5 is separate from the fixing portion 6. In addition, the terminal fastening portion 5 and the fixing portion 6 are easy to mold, and the mold is also easy to form.

(5) The terminal fastening portion 5 is formed by integrating the terminal 71 and the resin. The terminal fastening portion 5 is disposed in the space S that overlaps the coils 31 and 32 in the axial direction without overlapping the core 2, so that the terminal 71 and the resin can be integrated by insert molding.

[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.

For example, the number of legs 21 and the number of coils 31, 32 are not limited to the above embodiment. There may be three or more legs 21. However, it is necessary to have a structure in which the coils 31, 32 are wound around at least the legs 21 at both ends in the direction in which the legs 21 are arranged, so that the space S generated above the coils 31, 32 can be utilized.

Reference Signs List 2 Core 21 Leg 22 Connecting portion 31, 32 Coil 3a Lead wire 4 Resin member 41 First resin member 41a Side surface 41b Bulging portion 42 Second resin member 5 Terminal fastening portion 51 Nut 6 Fixing portion 61 Collar 7 Bus bar 71 Terminal 71a Mounting hole 72 End portion 10 Reactor C Connection portion S Space

Claims (5)

A core having a plurality of legs and a pair of connecting portions connecting end portions of the plurality of legs;
A coil is attached to each of the legs at both ends in an arrangement direction of the plurality of legs;
A resin member that covers the connecting portion;
having
The resin member covering one of the connecting portions has
terminal fastening portions provided at both ends of the connecting portion at positions where the coil overlaps with the winding axis, the terminal supporting the coil for electrically connecting the coil to the outside, and a fastener fastened to the coil with a direction parallel to the winding axis as an axis;
a fixing portion provided adjacent to the terminal fastening portion at a position where the coil and the winding axis do not overlap with each other in a direction of the winding axis, the fixing portion being fixed to the fixing device with an axis parallel to the winding axis;
A reactor comprising: A connection portion is provided between an end of the coil and the terminal,
The reactor according to claim 1 , wherein the connection portion is disposed adjacent to the terminal fastening portion in a direction different from that of the fixed portion. The resin member covering the connecting portion has a longitudinal direction in which the legs are arranged and a lateral direction perpendicular to the longitudinal direction,
3. The reactor according to claim 1, wherein the terminal fastening portion and the fixing portion are provided on a side surface of the resin member along the short side direction. The reactor according to any one of claims 1 to 3, characterized in that the terminal fastening portion and the fixing portion are formed seamlessly and continuously. 5. The reactor according to claim 1, wherein the terminal fastening portion is formed by integrating the terminal and a resin.

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