JP2011124310A - Reactor - Google Patents

Abstract

The present invention provides a reactor capable of positioning a rotational position of a coil with respect to a case at the time of assembly and having excellent assemblability.
A reactor includes a coil that is formed by winding a winding, a columnar inner core portion that is inserted into the coil, and a connecting core portion that covers at least a part of the outer periphery of the coil. A magnetic core 20 that forms a closed magnetic path with both the core portions, and a case 30 that houses a combined body of the coil 10 and the magnetic core 20. The inner core portion 21 has a saturation magnetic flux density higher than that of the connecting core portion 22. The connecting core part 22 has a lower magnetic permeability than the inner core part 21, and is composed of a mixture of a magnetic material and a resin. The inner core portion 21 and the connecting core portion 22 are integrated in the case 30 with resin. And it has rotation positioning means (block 41) for positioning the rotation position of the coil 10 with respect to the case 30 by stopping the winding end 11 of the coil 10 [Selection] FIG.

Description

  The present invention relates to a reactor used for a component part of a power conversion device such as an in-vehicle DC-DC converter. In particular, the present invention relates to a reactor that can position a rotating position of a coil with respect to a case at the time of assembly and has excellent assemblability.

  A reactor is one of the parts of a circuit that performs a voltage step-up operation or a voltage step-down operation. For example, as a reactor used in a converter mounted on a vehicle such as a hybrid vehicle, a configuration in which a pair of coil elements formed by winding a coil is arranged in parallel on the outer periphery of an O-shaped annular magnetic core Is the mainstream.

  In addition, for example, in Patent Document 1, a cylindrical inner core portion disposed on the inner periphery of one coil, and a cylindrical outer core piece disposed on the outer side of the coil so as to cover the outer peripheral surface of the coil, In addition, a magnetic core having an E-shaped cross section including a pair of disk-shaped connecting core pieces disposed on each end face of the coil, a reactor including a so-called pot-type core is disclosed (see Patent Document 1 and FIG. 1). ). In the pot-type core of Patent Document 1, the inner core portion and the outer core piece arranged concentrically are connected by the connecting core piece to form a closed magnetic circuit.

  Parts with a small installation space such as in-vehicle parts are desired to be small. Patent Document 1 proposes that the inner core portion has a saturation magnetic flux density higher than that of the outer core piece and the connecting core piece, thereby reducing the cross-sectional area of the inner core portion and reducing the size of the reactor.

JP 2009-33051 A

  As one method of manufacturing a reactor having a pot-type core, magnetic powder (magnetic material) is used as a constituent material of an outer core piece and a connecting core piece (which are simply referred to as a connecting core portion) that covers the outer periphery of the coil. It is conceivable to use a mixture of resin and resin. Then, these members are housed in the case with the coil arranged on the outer periphery of the inner core portion, the mixture is filled in the case, and the case is used as a mold to solidify the resin, thereby connecting the connecting core portion. It is conceivable to perform integral molding. Further, the inner core portion and the connecting core portion are integrated in the case by the resin.

  However, in such a manufacturing method, when the case is filled with the mixture, the coil rotates and the rotational position of the coil with respect to the case may shift from a predetermined rotational position. Inconveniences such as the inability to arrange the terminal block connected to the terminal are likely to occur.

  The present invention has been made in view of the above circumstances, and one of its purposes is to provide a reactor that can position a rotating position of a coil with respect to a case at the time of assembly and has excellent assemblability.

  In the present invention, the above object is achieved by providing rotational positioning means for positioning the rotational position of the coil with respect to the case by stopping the winding end of the coil in the reactor.

  The reactor according to the present invention includes a coil formed by winding a coil, a columnar inner core portion inserted into the coil, and a core portion connected to cover at least a part of the outer periphery of the coil. And a magnetic core that forms a path. A combination of a coil and a magnetic core is housed in the case. The inner core portion has a saturation magnetic flux density higher than that of the connecting core portion, the connecting core portion has a lower magnetic permeability than the inner core portion, and is composed of a mixture of a magnetic material and a resin. The inner core portion and the connecting core portion are integrated in the case with resin. And it has the rotation positioning means which positions the rotation position of the coil with respect to the case by stopping the winding end of the coil.

  According to this configuration, by having the rotation positioning means, it is possible to position the rotation position of the coil with respect to the case by stopping the winding end of the coil. Therefore, a reactor is formed by using a mixture of a magnetic material and a resin as a constituent material of the connecting core portion, filling the mixture with the inner core portion and the coil housed in the case, and integrally forming the connecting core portion. When assembling, the coil can be prevented from rotating, and the assemblability is excellent.

  In the reactor of the present invention, the magnetic core can have a so-called gapless structure without a solid gap material made of a nonmagnetic material such as an alumina plate. By adopting a gapless structure, noise due to vibration caused by magnetic attraction in the gap cannot occur.

  Since the reactor of the present invention has a single coil and a so-called pot-type core, the reactor is smaller than a conventional reactor having a plurality of coil elements.

  In the reactor of the present invention, the magnetic core is not made of a uniform material, but is made of a different material, so that the magnetic properties of the magnetic core are partially different as described above. Specifically, the saturation magnetic flux density of the inner core portion is higher than the saturation magnetic flux density of the connection core portion. Therefore, when the magnetic core is made of a uniform material and the same saturation magnetic flux density is obtained as compared with the magnetic core having a uniform saturation magnetic flux density and permeability throughout the entire core, The cross-sectional area of the core portion can be reduced to reduce the size. In addition, if the gapless structure is used as described above, even when the inner core portion is arranged in the coil, even if the inner peripheral surface of the coil is placed close to the outer peripheral surface of the inner core portion, the effect of leakage magnetic flux in the gap Loss due to cannot occur. Therefore, the clearance gap between a coil and an inner core part can be made small, Preferably this clearance gap can be substantially eliminated. Here, when the magnetic core has a gap material, if the coil is placed close to the gap portion, the influence of the leakage magnetic flux from the gap reaches the coil and a loss occurs. Therefore, when a magnetic core having a gap material is used, it is necessary to provide a certain gap between the inner peripheral surface of the coil and the outer peripheral surface of the inner core portion in order to reduce the loss. On the other hand, in the case of a gapless structure, the loss does not occur even if the inner peripheral surface of the coil is disposed close to the outer peripheral surface of the inner core portion, and the coil and the inner core portion are disposed closer to each other. Can be downsized.

  This invention reactor can fully satisfy | fill predetermined | prescribed inductance because the magnetic permeability of a connection core part is lower than the magnetic permeability of an inner core part. In particular, since the connecting core portion can easily change the magnetic characteristics by adjusting the ratio of the magnetic material and the resin, it is easy to adjust the inductance of the reactor. Moreover, this invention reactor can obtain the predetermined characteristic desired for each core part with a sufficient precision by making an inner core part and a connection core part into a separate member.

  In the reactor according to the present invention, the constituent material of the connecting core portion is a mixture of a magnetic material and a resin, and the inner core portion and the connecting core portion are integrated by this resin. Moreover, a coil and an inner core part can also be integrated with the material resin of a connection core part. For example, by forming the connecting core portion so as to cover the outer periphery of the assembly of the coil and the inner core portion, a magnetic core having predetermined characteristics can be formed, and a reactor can be manufactured. Thus, the formation of the connecting core part, the formation of the magnetic core, and the production of the reactor can be performed simultaneously, and the productivity is excellent.

  As described above, the reactor of the present invention has excellent effects such as miniaturization, ease of adjustment of inductance, and improvement of productivity in addition to positioning of the rotational position of the coil with respect to the case during assembly.

  As one form of the present invention, a form in which the rotation positioning means is formed integrally with the case, and a form in which the rotation positioning means is formed by a separate member from the case and are attached to the case can be mentioned. The rotational positioning means is constituted by, for example, a protrusion that holds the winding end of the coil and a notch that sandwiches the winding end.

  The reactor of the present invention preferably further includes a height positioning means for positioning the height position of the coil with respect to the case.

  By having the height positioning means, the height position of the coil can be uniquely determined at the time of assembling, and the assemblability is further improved. For example, the height positioning means may be provided on the bottom surface of the case so that the surface of the coil facing the bottom surface of the case is at a predetermined height with respect to the bottom surface of the case. Further, the height positioning means may be formed integrally with the case as well as the rotation positioning means, or may be formed by a member separate from the case and attached to the case.

  Since the reactor of the present invention has the rotation positioning means, the rotation position of the coil with respect to the case can be positioned at the time of assembly, and the assembly is excellent.

(A) is a schematic perspective view of the reactor which concerns on Embodiment 1, (B) is sectional drawing of arrow AA of the figure (A). (A) is a schematic top view of the reactor which concerns on Embodiment 1, (B) is sectional drawing of the case seen from arrow AA of FIG. 1 (A). It is a schematic exploded view for demonstrating the member which comprises the reactor which concerns on Embodiment 1. FIG. It is a schematic perspective view of the reactor which concerns on Embodiment 2. FIG. 6 is a schematic perspective view of a reactor according to Embodiment 3. FIG. (A) is a schematic top view of the case of the reactor which concerns on Embodiment 4, (B) is sectional drawing of arrow BB of the figure (A).

  Embodiments of the present invention will be described below with reference to the drawings. In addition, the same code | symbol in a figure shows the same or an equivalent part.

(Embodiment 1)
With reference to FIGS. 1-3, the reactor 1 which concerns on Embodiment 1 is demonstrated. The reactor 1 is a case that houses a coil 10 formed by winding a coil, a magnetic core 20 that is a path of magnetic flux generated when the coil 10 is energized, and a combination of the coil 10 and the magnetic core 20 30. The magnetic core 20 includes an inner core portion 21 that is inserted into the coil 10 and a connecting core portion 22 that is not disposed in the coil 10 and covers the outer periphery of the coil 10. The feature of the reactor 1 is that it has a rotation positioning means for positioning the rotation position of the coil 10 with respect to the case 30. Hereinafter, each configuration will be described in detail.

[coil]
The coil 10 is a cylindrical body formed by spirally winding one continuous winding 10w. The winding 10w is preferably a coated wire in which a copper or aluminum conductor is coated with an insulating coating. Here, the coil 10 is an edgewise-wound cylindrical coil in which a conductor is made of a flat rectangular wire and an insulating covering is made of enamel. By performing edgewise winding, it is easy to increase the space factor of the conductor, and by making it cylindrical, it is excellent in formability compared to a rectangular tube. As the winding 10w, a conductor having a rectangular wire shape and various shapes such as a circular shape and a polygonal shape can be used.

  As shown in FIG. 1B, the coil 10 is housed in the case 30 so that the axial direction of the coil 10 is substantially orthogonal to the bottom surface 31 of the case 30. That is, one end face of the coil 10 and the bottom face 31 of the case 30 face each other. In this example, both ends of the winding 10w are bent at the end of the turn of the coil 10 (see FIG. 3), and both winding ends 11, 12 are extended along the axial direction of the coil. It is pulled out to the outside of the connecting core part 22 described later.

  Although not shown here, the insulating coating is peeled off at the tips of the winding end portions 11 and 12 to expose the conductor, and the terminal portion of the terminal block is connected to this portion. Then, an external device such as a power source that supplies current to the coil 10 is connected via the terminal portion. In addition to welding such as TIG welding, crimping or the like can be used to connect the conductor of the winding 10w and the terminal portion.

[Magnetic core]
The magnetic core 20 includes an inner core portion 21 that is inserted into the coil 10 and a connecting core portion 22 that is formed so as to cover the assembly of the inner core portion 21 and the coil 10. In the magnetic core 20, the constituent material of the inner core portion 21 and the constituent material of the connecting core portion 22 are different, and magnetic characteristics are partially different. Specifically, the inner core portion 21 has a higher saturation magnetic flux density than the connecting core portion 22, and the connecting core portion 22 has a lower magnetic permeability than the inner core portion 21.

<Inner core part>
The inner core portion 21 has an outer shape corresponding to the shape of the inner peripheral surface of the cylindrical coil 10. That is, the inner core portion 21 is a cylindrical body having a circular end surface as shown in FIG. The inner core portion 21 is housed in the case 30 with one end surface abutting against the bottom surface 31 of the case 30 so that the axial direction of the coil 10 is substantially orthogonal to the bottom surface 31 of the case 30 (FIG. 1 ( B)). Further, since the entire inner core portion 21 is composed of a powder compact, a solid gap material such as an alumina plate, an air gap, or an adhesive is not interposed.

  Typically, the green compact can be obtained by molding a soft magnetic powder having an insulating coating on the surface into a predetermined shape and then firing it at a temperature lower than the heat resistance temperature of the insulating coating. A mixed powder in which a binder is appropriately mixed in addition to the soft magnetic powder can be used, or a powder having a coating such as a silicone resin can be used as an insulating coating. The saturation magnetic flux density of the green compact can be changed by adjusting the characteristics of the soft magnetic powder itself, the mixing ratio of the soft magnetic powder and the binder, the type and amount (thickness) of the coating. For example, a compacted body having a high saturation magnetic flux density can be obtained by using a soft magnetic powder having a high saturation magnetic flux density or by increasing the proportion of the soft magnetic powder by reducing the blending amount of the binder. In addition, the saturation magnetic flux density tends to be increased by changing the molding pressure, specifically, by increasing the molding pressure. It is preferable to select a soft magnetic powder and adjust a molding pressure so as to obtain a desired saturation magnetic flux density.

  Soft magnetic powders include Fe group metal powders such as Fe, Co, and Ni, and Fe-based alloy powders such as Fe-Si, Fe-Ni, Fe-Al, Fe-Co, Fe-Cr, and Fe-Si-Al. Alternatively, rare earth metal powder, ferrite powder or the like can be used. In particular, the Fe-based alloy powder is easy to obtain a green compact with a high saturation magnetic flux density. Such a powder can be produced by an atomizing method (gas or water), a mechanical pulverization method, or the like. In particular, when a powder made of a nanocrystalline material whose crystals are nano-sized, preferably a powder made of an anisotropic nanocrystalline material, a compact with a high anisotropy and a low coercive force is obtained. For the insulating coating formed on the soft magnetic powder, for example, a phosphoric acid compound, a silicon compound, a zirconium compound, or a boride can be used. As the binder, for example, a thermoplastic resin, a non-thermoplastic resin, or a higher fatty acid can be used. The binder may be burned off by firing or may be changed to an insulator such as silica. Since the compacting body has an insulating coating formed on the surface of the soft magnetic powder, direct contact between the soft magnetic powders can be prevented and eddy current loss can be reduced. As a result, eddy current loss can be reduced even when a high-frequency current is applied to the coil 10. A well-known thing may be utilized for a compacting body.

  The shape of the inner core portion 21 can be selected as appropriate. For example, the inner core portion 21 can be formed in a prismatic shape. Furthermore, the inner core portion 21 may be formed of a laminate in which electromagnetic steel plates are laminated.

  In the reactor 1, as shown in FIG. 1B, the axial length of the inner core portion 21 is slightly longer than the length of the coil 10, and both end surfaces of the inner core portion 21 protrude from the end surfaces of the coil 10. Yes. Here, the length of the inner core portion 21 may be equal to the length of the coil 10 or may be slightly shorter. The length of the inner core portion 21 is equal to or greater than the length of the coil 10, and the inner core portion 21 is arranged over the entire length of the coil 10, so that the magnetic flux generated by the coil 10 is transferred to the inner core portion 21. It can be passed sufficiently.

<Linked core part>
The connecting core part 22 is connected to the inner core part 21 so that the magnetic core 20 forms a closed magnetic path. As shown in FIG. 1 (B), the connecting core portion 22 is substantially the entire surface of the assembly of the coil 10 and the inner core portion 21 inserted through the coil 10, that is, the outer peripheral surface and both end surfaces of the coil 10. The inner core portion 21 is formed in a rectangular parallelepiped shape so as to substantially cover the other end surface (the end surface opposite to the one end surface in contact with the bottom surface 31 of the case 30). Specifically, in the reactor 1, the outer shape of the connecting core portion 22 is the same as the shape of the space formed by the inner peripheral surface of the case 30. The reactor 1 has a gapless structure in which the inner core portion 21 and the connecting core portion 22 are integrated with a material resin to be described later of the connecting core portion 22 without an adhesive. Further, in the reactor 1, the coil 10, the inner core portion 21, and the connection core portion 22 are integrated by the material resin of the connection core portion 22.

  The shape of the connecting core portion 22 is not particularly limited as long as the magnetic core 20 can form a closed magnetic path. For example, the length of the inner core portion 21 may be longer than the length of the coil 10, and at least one end surface of the inner core portion 21 may be exposed from the connecting core portion 22. Alternatively, at least a part of the outer peripheral surface of the coil 10 may be exposed from the connecting core portion 22. Here, as will be described later, the case 30 is used as a mold and the connecting core portion 22 is formed.

  The entire connecting core portion 22 is composed of a mixture (molded and cured body) of a magnetic material and a resin. For example, the connecting core portion 22 is obtained by mixing soft magnetic powder of a magnetic material and a flowable binder resin, filling the mixture by pouring the mixture into the case 30 under a predetermined pressure, and then solidifying the resin. Obtainable. Alternatively, the mixture may be injected and filled into the case 30 without applying pressure to solidify the resin. Moreover, you may add a nonmagnetic powder to a mixture as needed. As the binder resin, for example, a thermosetting resin such as an epoxy resin, a phenol resin, or a silicone resin can be suitably used. When a thermosetting resin is used as the binder resin, the resin is heat-cured by heating together with the mold (case 30). As the binder resin, a room temperature curable resin or a low temperature curable resin may be used. In this case, the resin can be cured while being kept at a room temperature to a relatively low temperature. Since the molded hardened body (connecting core part 22) contains a large amount of binder resin, which is a non-magnetic material, even if the same soft magnetic powder as that of the green compact (inner core part 21) is used, However, the saturation magnetic flux density is low and the magnetic permeability is also low. Further, since the connecting core portion 22 includes a resin component, the coil 10 and the inner core portion 21 can be protected from an external environment such as moisture and dust and mechanical stress.

  The molded hardened body can also adjust the magnetic permeability by changing the characteristics of the soft magnetic powder itself, the mixing ratio of the soft magnetic powder and the binder resin (including nonmagnetic powder), and the like. For example, when the proportion of soft magnetic powder is reduced, the magnetic permeability is lowered. The magnetic permeability of the connecting core portion 22 may be adjusted so that the reactor 1 satisfies a desired inductance.

  As the soft magnetic powder used for the connecting core portion 22, the same soft magnetic powder as used for the inner core portion 21 described above can be used.

<Case>
The case 30 houses an assembly of the coil 10 and the magnetic core 20, and is made of a metal such as aluminum. As shown in FIGS. 1 and 2, the case 30 has a bottom box 31 and side walls (a front wall 32, side walls 33 and 34, and a back wall 35) standing from the bottom 31, and a square box having an open top surface. It is a state. In this example, the coil 10 is housed so that the winding end portions 11 and 12 are positioned on the front wall 32 side. By storing the above-described combination in the case 30, the coil 10 and the magnetic core 20 can be protected from the external environment and mechanical stress. As shown in FIG. 2, a concave guide portion 36 having a shape corresponding to the shape of the outer peripheral surface of the coil 10 is formed on the inner peripheral surface of the side walls 33 and 34 of the case 30. When 10 is accommodated in the case 30, the horizontal positioning with respect to the bottom surface 31 is easy. Further, the case 30 is provided with an insertion hole 37 through which a fixing metal fitting (for example, a bolt) is inserted and fixed to the installation target.

<Rotating positioning means>
The rotational positioning means positions the rotational position of the coil 10 with respect to the case 30, and is formed integrally with the case 30 in the reactor 1. Here, as shown in FIG. 2, the front wall 32 of the case 30 and the winding end 11 extended from one end surface of the coil 10 (the end surface facing the bottom surface 31 of the case 30) A block 41 extending from the bottom surface 31 to the top surface is provided at a corner with the side wall 33, and this block 41 is used for rotational positioning means. The winding end portion 11 of the coil 10 is disposed so as to pass between the block 41 and the guide portion 36 formed on the side wall 33. Even when the coil 10 is about to rotate, the winding end 11 of the coil 10 is stopped by the block 41 and the guide portion 36, and the rotational position of the coil 10 with respect to the case 30 is positioned.

  In this example, the block 41 is provided from the bottom surface 31 to the upper surface of the case 30, but the block 41 is provided only on the upper surface side of the case 30, for example, so that a part of the winding end 11 is stopped. May be. Further, the block 41 may be formed by a member separate from the case 30 and attached to the case 30. In this case, for example, if the block 41 is formed of the same material as the constituent material of the connection core part 22, it can be used as a part of the connection core part 22. On the other hand, for example, if the block 41 is formed of a material such as a metal having a high thermal conductivity (for example, aluminum) or ceramics, heat dissipation can be improved.

<Others>
Insulation between the coil 10 and the magnetic core 20 can be ensured by the above-described insulation coating of the winding 10w. In order to make the insulation more reliable, an insulator may be interposed at a location where the coil 10 is in contact with the magnetic core 20. For example, an insulating tape may be attached to the inner and outer peripheral surfaces of the coil 10, or insulating paper or an insulating sheet may be disposed. Further, a cylindrical bobbin (not shown) made of an insulating material may be disposed on the outer periphery of the coil 10 or the outer periphery of the inner core portion 21. In particular, if the bobbin disposed on the outer periphery of the inner core portion 21 has an annular flange portion extending in the outer peripheral direction from both ends, it is easy to ensure insulation between both end surfaces of the coil 10 and the connecting core portion 22. For example, an insulating resin such as a polyphenylene sulfide (PPS) resin, a liquid crystal polymer (LCP), or a polytetrafluoroethylene (PTFE) resin can be suitably used as the constituent material of the bobbin.

[Reactor manufacturing method]
The reactor 1 can be manufactured as follows, for example. First, the coil 10 and the inner core portion 21 made of a compacted body are prepared, and the inner core portion 21 is inserted into the coil 10 to produce a combination of the coil 10 and the inner core portion 21 (FIG. 3). reference). At this time, an insulator may be appropriately interposed between the coil 10 and the inner core portion 21 as described above. Next, the assembly of the coil 10 and the inner core portion 21 is stored in a predetermined position in the case 30. Specifically, the winding end portion 11 of the coil 10 is disposed so as to pass between the block 41 and the guide portion 36 formed on the side wall 33 as described above. At this time, the coil 10 is supported so that a predetermined gap is formed between one end surface of the coil 10 (the end surface facing the bottom surface 31 of the case 30) and the bottom surface 31 (see FIG. 2B). Keep it.

  Next, the case 30 containing the assembly is filled with the constituent material of the connecting core portion 22, that is, a mixture of soft magnetic powder and binder resin, and the resin is cured to integrally form the connecting core portion 22. To do. Note that the connecting core portion 22 may be formed in a plurality of times, and an intermediate molded product of the connecting core portion 22 at an intermediate stage may be used for positioning the height position of the coil 10. Specifically, in a state where the coil 10 is not housed in the case 30, a part of the mixture is filled in the case 30 and cured, and only a part of the connecting core portion 22 is molded, and then the intermediate molded product is placed on the intermediate molded product. The coil 10 is disposed. Thereafter, the remaining portion of the connecting core portion 22 is molded, and the remaining portion and the intermediate molded product are integrated with resin to completely form the connecting core portion 22.

[effect]
The reactor 1 has a block 41 (rotating positioning means) formed integrally with the case 30. With this configuration, the reactor 1 can stop the winding end 11 of the coil 10 and position the rotational position of the coil 10 with respect to the case 30. Therefore, when the mixture of the magnetic material and the resin is used as the constituent material of the connecting core portion 22 and the mixture is filled with the coil 10 stored in the case 30, the rotation of the coil 10 can be prevented. Excellent assembly.

  Further, when the reactor 1 has a saturation magnetic flux density of the inner core portion 21 higher than that of the connecting core portion 22, the cross-sectional area of the inner core portion 21 (the magnetic flux is (Passing surface) can be reduced. By downsizing the inner core portion 21, the magnetic core 20 can be reduced in size, and the reactor 1 can be reduced in size. In addition, the reactor 1 has a high saturation magnetic flux density of the inner core portion 21 where the coil 10 is disposed and a low permeability of the connecting core portion 22 where the coil 10 is not disposed, so that a desired inductance is easily satisfied. Furthermore, since the reactor 1 has no gap including the adhesive throughout the magnetic core 20, the influence of the leakage magnetic flux from the gap does not affect the coil 10 and no loss occurs. The inner peripheral surface of the coil 10 can be disposed close to the outer peripheral surface of the portion 21. Therefore, the gap between the inner peripheral surface of the coil 10 and the outer peripheral surface of the inner core portion 21 can be reduced, and from this, the reactor 1 can be reduced in size. In particular, the reactor 1 can reduce the above-described gap by making the outer shape of the inner core portion 21 a columnar shape along the shape of the inner peripheral surface of the coil 10.

  Further, the reactor 1 forms the connecting core portion 22 and at the same time forms the magnetic core 20 that forms the closed magnetic path by integrating the inner core portion 21 and the connecting core portion 22 with the material resin of the connecting core portion 22. Manufactured by. Thus, the reactor 1 has few manufacturing processes and is excellent in productivity.

  In addition, since the reactor 1 has an adhesive-less structure, variations in inductance due to variations in the thickness of the adhesive hardly occur.

(Embodiment 2)
With reference to FIG. 4, the reactor 2 which concerns on Embodiment 2 is demonstrated. The reactor 2 is different from the reactor 1 according to the first embodiment shown in FIGS. 1 to 3 in the form of the rotation positioning means, and the other points are substantially the same as the reactor 1 according to the first embodiment. Description is omitted.

<Rotating positioning means>
In the reactor 2, the rotation positioning means is formed integrally with the case 30. Here, as shown in FIG. 4, two notches 42 are provided on the upper edge of the front wall 32 of the case 30 so as to sandwich the winding ends 11 and 12 of the coil 10 drawn out by bending. The notch 42 is used as a rotational positioning means. The winding end portions 11 and 12 of the coil 10 are respectively hooked so as to be sandwiched between the notches 42. Even when the coil 10 is about to rotate, the winding ends 11 and 12 of the coil 10 are abutted by the notches 42, and the rotational position of the coil 10 relative to the case 30 is positioned.

[effect]
The reactor 2 has a notch 42 (rotational positioning means) formed integrally with the case 30. With this configuration, the reactor 2 can stop the winding end portions 11 and 12 of the coil 10 and position the rotational position of the coil 10 with respect to the case 30. Therefore, when the mixture of the magnetic material and the resin is used as the constituent material of the connecting core portion 22 and the mixture is filled with the coil 10 stored in the case 30, the rotation of the coil 10 can be prevented. Excellent assembly.

  Further, the reactor 2 can be positioned at the height position of the coil 10 by bending the winding end portions 11 and 12 of the coil 10 and hooking them on the notches 42.

(Embodiment 3)
With reference to FIG. 5, the reactor 3 which concerns on Embodiment 3 is demonstrated. The reactor 3 is different from the reactor 1 according to the first embodiment shown in FIGS. 1 to 3 in the form of the rotation positioning means, and the other points are substantially the same as the reactor 1 according to the first embodiment. Description is omitted.

<Rotating positioning means>
In the reactor 3, the rotation positioning means is formed by a member separate from the case 30. Here, as shown in FIG. 5, a stopper member 43 having two protrusions 44 is attached to the upper edge of the front wall 32 of the case 30, and this stopper member 43 is used as rotational positioning means. The winding end portions 11 and 12 of the coil 10 are arranged so that the projection 44 of the stopper member 43 is sandwiched between them. The stopper member 43 is attached by being fitted into a recess 38 provided on the upper edge of the front wall 32 of the case 30 so that the protruding portion 44 faces the inner peripheral surface of the case 30. Even when the coil 10 is about to rotate, the winding end portions 11 and 12 of the coil 10 are abutted by the protrusions 44 of the abutting member 43, and the rotational position of the coil 10 with respect to the case 30 is positioned.

  The stopper member 43 can be made of various materials such as metal, resin, and ceramics. For example, if formed of a material such as a metal having high thermal conductivity (eg, aluminum) or ceramics, heat dissipation can be enhanced, while if formed of a material such as a highly insulating resin or ceramic, Insulation from 11 and 12 can be secured. Further, when the connecting core portion 22 is formed of the same material as the constituent material, it can be used as a part of the connecting core portion 22.

[effect]
In the reactor 3, a stopper member 43 (rotational positioning means) formed by a member separate from the case 30 is attached to the case 30. With this configuration, the reactor 2 can stop the winding end portions 11 and 12 of the coil 10 and position the rotational position of the coil 10 with respect to the case 30. Therefore, when the mixture of the magnetic material and the resin is used as the constituent material of the connecting core portion 22 and the mixture is filled with the coil 10 stored in the case 30, the rotation of the coil 10 can be prevented. Excellent assembly.

(Embodiment 4)
In the fourth embodiment, a reactor having a height positioning means for positioning the height position of the coil 10 with respect to the case 30 will be described with reference to FIG. The reactor according to the fourth embodiment is different from the case used in the reactor 1 according to the first embodiment shown in FIGS. 1 to 3 in the form of the case, and the other points are the case of the reactor 1 according to the first embodiment. The description is omitted since it is substantially the same.

<Height positioning means>
In the case 30 shown in FIG. 6, a pedestal 51 is formed integrally with the case 30 and protrudes from the bottom 31 side of the guide 36 formed on the side walls 33, 34 toward the inner peripheral surface of the case 30. The pedestal 51 is used as a height positioning means. The height position of the coil 10 can be uniquely determined by bringing a part of one end surface of the coil 10 (the end surface facing the bottom surface 31 of the case 30) into contact with the pedestal portion 51. Excellent assemblability.

  The pedestal 51 may be formed by a member separate from the case 30 and attached to the case 30. In this case, for example, if the pedestal portion 51 is formed of the same material as the constituent material of the connection core portion 22, it can be used as a part of the connection core portion 22. On the other hand, for example, if the pedestal 51 is formed of a material such as a metal having a high thermal conductivity (eg, aluminum) or ceramics, heat dissipation can be improved. In addition, when formed of a material such as highly insulating resin or ceramic, insulation from the coil 10 can be secured.

(Modification 1)
In the first to fourth embodiments described above, the configuration has been described in which the insulation between the coil and the magnetic core is ensured by the insulating coating of the windings constituting the coil and the insulator interposed separately. In addition, it can be set as the coil molded object provided with the inner side resin part which covers the surface of a coil. Moreover, it is good also as a coil molded object which shape | molded the coil and the inner core part integrally by this inner side resin part.

  As the constituent material of the inner resin portion, an insulating resin that has heat resistance to the operating temperature of the reactor and can be transfer molded or injection molded can be suitably used. For example, a thermosetting resin such as epoxy, or a thermoplastic resin such as PPS resin or LCP can be suitably used. When such a resin is further mixed with a filler made of at least one ceramic selected from silicon nitride, alumina, aluminum nitride, boron nitride, and silicon carbide, the heat of the coil is easily released, The heat dissipation of the reactor can be improved. In addition, the inner resin portion may hold the coil in a state compressed more than the free length, and the length of the coil may be adjusted as appropriate.

  In the above-described coil molded body, a coil and a core, or a coil and an inner core part are arranged in a mold, and the resin constituting the inner resin part is filled in the mold and solidified by appropriately compressing the coil. By making it, it can manufacture. Such a coil molded body can utilize the manufacturing method of the coil molded body described in Unexamined-Japanese-Patent No. 2009-218293, for example.

  By using such a coil molded body, the insulation between the coil and the magnetic core can be improved, and the outer shape of the coil is held by the inner resin part during assembly of the reactor, making it easy to handle the coil. Excellent reactor assembly.

  Note that the present invention is not limited to the above-described embodiment, and can be modified as appropriate without departing from the gist of the present invention. For example, the shape, structure, and arrangement of the rotation positioning unit and the height positioning unit may be changed as appropriate. Moreover, it is good also as a form which accommodates a coil and an inner core part in a case so that the axial direction of a coil may become substantially parallel with respect to the bottom face of a case.

  The reactor of the present invention can be used as a component part of a power conversion device such as a bidirectional DC-DC converter mounted on an electric vehicle such as a hybrid vehicle, an electric vehicle, or a fuel cell vehicle.

1,2,3 reactor
10 Coil 10w Winding 11,12 Winding end
20 Magnetic core
21 Inner core 22 Linked core
30 cases
31 Bottom 32 Front wall 33,34 Side wall 35 Back wall
36 Guide part 37 Insertion hole 38 Recess
41 Block 42 Notch 43 Stopping member 44 Projection
51 pedestal

Claims (4)

One coil formed by winding a winding;
A magnetic core that forms a closed magnetic path with both core portions of a columnar inner core portion inserted into the coil and a connecting core portion that covers at least a part of the outer periphery of the coil,
A combination of the coil and the magnetic core is housed in a case,
The inner core portion has a higher saturation magnetic flux density than the connecting core portion,
The connecting core portion has a lower magnetic permeability than the inner core portion, and is composed of a mixture of a magnetic material and a resin,
The inner core portion and the connecting core portion are integrated in the case by the resin,
A reactor having a rotation positioning means for positioning a rotation position of the coil with respect to the case by stopping the winding end of the coil.   The reactor according to claim 1, wherein the rotation positioning unit is formed integrally with the case.   The reactor according to claim 1, wherein the rotation positioning unit is formed of a member separate from the case and is attached to the case.   The reactor according to claim 1, further comprising a height positioning unit that positions a height position of the coil with respect to the case.

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