JP5208187B2 - Reactor device - Google Patents

Description

  INDUSTRIAL APPLICABILITY The present invention is suitable for a reactor device used for a power converter, particularly for in-vehicle use in which magnetic characteristics are stabilized while reducing variations, shortening work time, and reducing costs by facilitating positioning. The present invention relates to a reactor device.

Conventionally, a reactor device is used as a part of a power converter, and is used as a circuit component of a DC / DC voltage converter, for example, as an energy storage / release element. During operation of the power converter, heat is generated when the coil of the reactor device is energized. In order to release this heat to the outside, a configuration in which heat is radiated to the outside through a heat radiating plate is adopted.
And in a reactor device applied to a power converter mounted on an electric powertrain of an automobile, a cover with a fin or a housing is brought into contact with an insulating member in a form in which a coil having good thermal conductivity is placed along the outer periphery of the coil. An attempt is made to increase the heat dissipation area and suppress the temperature rise (see, for example, Patent Document 1).

JP 2002-50527 A

However, when positioning is not performed in the integrated case, the positional deviation is large due to tolerances and variations of screw members and holding members, etc., and this positional deviation causes the distance from the main cooling surface and the distance from the other cooling surface to increase. The variation and the unevenness of heat generation when the entire reactor is viewed as one component increase, so it is necessary to take into account thermal runaway and failure of surrounding electronic components due to concentrated radiant heat.
Variation in heat dissipation performance leads to individual variations in coil and resin temperature rise, making it difficult to raise the instantaneous rating.
In addition, as described above, when positioning is not performed in an integrated case and component position variation is large, voltage ripples and current ripples appearing externally vary, magnetic characteristics are not stable, and margin folding into other component specifications increases. In addition, the cost and size of the parts are increased.
Furthermore, even if the magnetic core and the coil are cooled, the leakage magnetic flux that does not pass through the magnetic core conducts through the case side portion that holds the reactor and the peripheral conductors such as the fixing and holding members. Since these parts generate heat, it is necessary to consider the heat dissipation in the case, fixing and holding member, which leads to high cost and large parts.
As described above, a product having a large number of individual parts incurs an individual part cost, and an assembly time during production increases, resulting in a high-cost product.

  The present invention has been made in order to solve the above-described problems, and reduces the heat generation of the coil and the core with a simple and compact configuration, and equalizes the heat distribution in the entire reactor. It is an object of the present invention to provide a structure that can improve the cooling efficiency and can reduce the size of the reactor.

The present invention is a reactor device having a case, a derivative component housed in the case, and a mold resin filled in a gap formed by the derivative component and the case, wherein the derivative component is A core that forms a magnetic path inside as a magnetic material, a coil in which a conductor winding is wound in a substantially cylindrical shape, and an insulating bobbin that positions and locks the winding portion of the coil on a columnar portion of the core And a sheet-like insulating member that insulates between the winding portion of the coil and the case, and the insulating bobbin extends along the axis on the inner side of the coil from both ends in the axial direction of the coil. The cylindrical cylindrical portion to be inserted and inserted is composed of a set of divided insulating bobbins that protrude from the center of the plane portion, and the cores are respectively formed from the outside of the insulating bobbins on both ends in the axial direction of the coil. , From the center of the surface side where the flat portion of the insulating bobbin is in contact with the end, a cylindrical columnar portion that is fitted into the cylindrical portion of the insulating bobbin along the axis, and from both ends of the side end portion, respectively. The outer legs extending along the outside of the coil are each composed of a set of divided magnetic cores projecting in the same direction, and the coil, the set of divided insulating bobbins, and the set of divided The magnetic core is integrated and accommodated in the case, and the case has a radius that is the same as the radius of the coil winding portion or twice the radius of the coil winding portion at the center of the inner bottom surface. A first protrusion having a radius and a concave cylindrical peripheral surface formed below is provided, and the derivative component is configured such that the coil winding portion is connected to the cylindrical peripheral edge of the case via the sheet-like insulating member. It is held in position by placing the Jo surface, upper Axial both ends by the respective divided insulating bobbin of the coil is fixed to the case, in a reactor and wherein the.

  The reactor device according to the present invention can minimize the influence on the periphery of electromagnetic waves and heat generation caused by the leakage magnetic flux generated in the gap existing in the core, and only insert the derivative component in the case. Since positioning can be performed easily, there is an effect that it is possible to improve manufacturing efficiency.

It is a perspective view which shows the reactor apparatus which concerns on Embodiment 1 of this invention. It is a disassembled perspective view which expands and shows the component of the reactor apparatus which concerns on Embodiment 1 of this invention. It is sectional drawing of the reactor apparatus in the cut surface A of FIG. It is sectional drawing of the reactor apparatus in the cut surface B of FIG. It is a figure which shows the external shape of the previous stage which accommodates a derivative component in a case. It is a perspective view which shows the detail of the inner bottom face of a case. It is a cross-sectional view for explaining the positional relationship between the inside of the case and the magnetic core as viewed from above the open surface of the case. The magnetic flux when there is a gap between the columnar portions of the magnetic core is shown. The magnetic flux in the case where there is a gap between the outer legs of the magnetic core is shown.

Hereinafter, preferred embodiments of a reactor device of the present invention will be described with reference to the drawings.
Embodiment 1 FIG.
1 is a perspective view showing a reactor apparatus according to Embodiment 1 of the present invention. FIG. 2 is an exploded perspective view showing the components of the reactor device in an exploded manner. Note that the same reference numerals denote the same or corresponding parts throughout the drawings.
A reactor device 1 according to Embodiment 1 of the present invention includes a case 2, a derivative component 3 accommodated in the case 2, and a mold resin 4 in which the derivative component 3 is immersed in the case 2.
The derivative component 3 is configured by combining divided insulating bobbins 5a and 5b, a coil 6, and divided magnetic cores 7a and 7b.
A thin plate-like insulating member 9 (not shown) is interposed between the winding portion 62 of the coil 6 and the inner bottom surface of the case 2.
The insulating bobbins 5a and 5b are structural parts formed by molding plastic and have electrical insulation properties.

  In FIG. 1, the mold resin 4 is shown transparent for convenience. In the following description, the insulating bobbins 5a and 5b may be collectively referred to as an insulating bobbin 5. Similarly, the magnetic cores 7a and 7b may be collectively referred to as a magnetic core 7, and the same applies to other members.

When applied to a DC / DC voltage converter (not shown), which is one of power converters, the dielectric component 3 has a function of conducting current to the coil 6 and storing and discharging energy as a derivative.
The magnetic cores 7a and 7b are formed by processing and molding a soft magnetic material. For example, an iron dust powder magnetic core, an electromagnetic steel plate, ferrite, Sendust, Permalloy, or the like is used.
The wire conductor constituting the coil 6 is an insulation coating with an enamel material, and a rectangular conductor having a substantially rectangular cross section is typically used to increase the space factor for the purpose of reducing the size of the reactor device 1.
The coil 6 is a so-called edgewise winding obtained by winding a flat conducting wire in the wide direction. Moreover, the coil 6 is arrange | positioned so that the columnar parts 72a and 72b which are the winding area | regions of the magnetic body core 7 corresponding to the winding part 62 of the coil 6 may be covered via the insulation bobbins 5a and 5b.
And the winding part 62 of the coil 6 is cylindrical shape, and the outer surface of the winding part 62 becomes a winding periphery.
The starting and terminating ends of the wire conductors are processed so as to become current conducting terminals 61 a and 61 b of the dielectric component 3. By changing the voltage applied between one terminal 61a and the other terminal 61b of the coil 6, a current flows between the terminals.

  In the reactor device 1 applied to the DC / DC voltage converter, the power semiconductor (not shown) connected to the terminals 61a and 61b is switched and switched to either the open state or the short-circuit state, whereby the terminal 61a of the coil 6 is switched. , 61b is adjusted. By adjusting the potential difference, the amount of increase and decrease of the current conducted to the coil 6 is controlled, and as a result, the accumulation and release of the energy stored in the reactor device 1 is adjusted to convert the voltage. At this time, increase / decrease of the current conducted to the coil 6 and switching of the polarity occur, and the amount of magnetic flux passing through the magnetic path in the magnetic core 7 changes.

The operating point of the magnetic core 7 moves on the BH characteristic line indicating the relationship between the magnetic flux density (B) and the magnetic field strength (H) by changing the amount of magnetic flux. A loss corresponding to the area of the region represented by the movement locus of the operating point occurs as a hysteresis loss of the magnetic core 7.
Further, with respect to the temporal change dΦcr / dt of the magnetic flux (Φcr) passing through the inside of the magnetic core 7, a vortex current that flows to soften the change in the magnetic flux flows inside the magnetic core 7, and this vortex shape Loss occurs as eddy current loss due to electric resistance in the current path.
The hysteresis loss and eddy current loss are collectively referred to as iron loss, which causes the magnetic core 7 to generate heat.

For example, when an electromagnetic steel plate is used as the magnetic material of the magnetic core 7, in order to reduce the eddy current loss of the magnetic core 7, the steel plate is a thin plate, an insulating film is formed on the surface layer, and the eddy current is laminated. Has been devised to reduce the loop diameter and reduce eddy current loss.
Further, when using, for example, an iron dust powder magnetic core as the magnetic material of the magnetic core 7, the iron dust material has a particle size of 100 μm or less, an insulating coating is formed on the surface of each particle, and the space between the particles is reduced. It is devised to reduce eddy current loss by insulation.

Further, a loss occurs in the coil 6 due to electric resistance against current conduction. The loss includes a DC component corresponding to the conduction of a direct current and an AC component corresponding to the conduction of an alternating current due to a change in current increase or decrease.
The cause of the AC component of the loss is the vortex generated inside the wire conductor due to the temporal change dΦi / dt of the magnetic flux (Φi) induced in the wire conductor of the coil 6 so as to prevent the current from increasing or decreasing. Due to the current, a phenomenon called a skin effect occurs in which the current does not easily conduct to the central portion of the wire conductor.
In addition, since the wire conductors are adjacent to each other in the winding portion 62 of the coil 6, a phenomenon called a proximity effect is generated in which current flows biased to the surface portions of the wire conductors.
In addition, as described above, the leakage magnetic flux in the magnetic gap portion of the magnetic core 7 is linked to the wire conductor of the coil 6, thereby causing a phenomenon in which loss is caused due to the eddy current generated in the wire conductor. .
The higher the current increase / decrease frequency is, the higher the interlinkage frequency fs of the leakage magnetic flux becomes, and the AC component of the loss of the coil 6 increases.
A combination of the DC component and AC component of the loss in the coil 6 is called copper loss, and the coil 6 generates heat.

As described above, the magnetic core 7 and the coil 6 generate heat, but the generated heat is transferred to the mold resin 4 and is transferred to the heat sink 11 through the case 2. The case 2 has a role of accommodating the dielectric component 3 and transferring the heat generated by the magnetic core 7 and the coil 6. When high heat dissipation is required, the metal is used for the purpose of increasing the thermal conductivity. Used.
Further, a part of the magnetic core 7 is in contact with the lower bottom surface inside the case 2, and heat is radiated toward the heat sink 11 through this contact portion.

Furthermore, the structure of the reactor apparatus 1 is demonstrated in detail with reference to FIG.2, FIG.3, FIG.4. 3 is a cross-sectional view of the reactor device 1 taken along the cut surface A of FIG. 1, and FIG. 4 is a cross-sectional view of the reactor device 1 taken along the cut surface B of FIG. 1 and shows the interior of the reactor device 1 according to the first embodiment. The structure is shown.
The cylindrical cylindrical portions 52a and 52b of the pair of insulating bobbins 5a and 5b are arranged to be fitted inside the coil 6, and the insulating bobbins 5a and 5b are abutted to each other so that the cylindrical portions 52a and 52b The tip (fitting part 52c) is fitted.
The columnar portions 72a and 72b of the magnetic cores 7a and 7b are fitted into the cylindrical portions 52a and 52b of the insulating bobbins 5a and 5b. The flat portions 53a and 53b of the insulating bobbins 5a and 5b are attached so as to contact the inner side surfaces of the side end portions 74a and 74b of the magnetic cores 7a and 7b.

On the surface from which the cylindrical portion 52a of the flat portion 53a of the insulating bobbin 5a protrudes, a protrusion is provided that determines the position of the portion rising from the winding portion 62 of the lead wire connected to the terminal 61a of the coil 6. The lead wire is restrained by the protrusion.
Similarly, a protrusion 54 is provided on the surface of the insulating bobbin 5b where the cylindrical portion 52b of the flat portion 53b protrudes to determine the position of the portion rising from the winding portion 62 of the lead wire connected to the terminal 61b of the coil 6. The lead wire is constrained by the protrusion 54.
In addition, although the protrusion provided in the plane part 53a is not illustrated in FIG. 2, it has the same shape as the protrusion 54 provided in the insulating bobbin 5b, and is provided at a position where the lead line rises.

In addition, protrusions 56a and 56b are provided on the upper end surface of the flat portion 53a of the insulating bobbin 5a to determine the position of the horizontally extending portion of the lead wire connected to the terminals 61a and 61b of the coil 6. It is restrained by 56a and 56b.
By constraining the terminals 61a and 61b of the coil 6 and the lead wires connected to them, the distance between the terminal 61a and the terminal 61b of the coil 6 can be set to a predetermined value, and between the terminals 61a and 61b. Even when a large potential difference is applied, an insulation distance (creeping distance) can be ensured so as to obtain a desired insulation resistance.

Further, the terminals 61a and 61b of the coil 6 are peeled off the enamel coating for insulation and joined to a wiring conductor (bus bar) (not shown), and the primary side of the DC / DC voltage converter and the main circuit Electrically connected to the semiconductor element.
The insulating bobbin 5a is provided with a terminal block 57 for joining the bus bars as an integral structure. The terminals 61a and 61b and the bus bar are electrically connected by welding, heat caulking, screw fastening using a crimp terminal, or the like.
However, throughout the drawings of the present invention, the terminals 61a and 61b of the coil 6 and the terminal block 57 of the insulating bobbin 5a are illustrated as being connected to the bus bar by screw fastening.

The outer leg 73a of the magnetic core 7a and the outer leg 73b of the magnetic core 7b are abutted and fixed by a fixing means such as an adhesive or a fixing member (not shown).
In some cases, the magnetic gap G is formed in the portion where the columnar portions 72a and 72b of the magnetic cores 7a and 7b are opposed to each other. In that case, a nonmagnetic material such as an adhesive, a mold resin, ceramic, air, or the like is provided in a region to be the magnetic gap G.

Next, accommodation of the derivative component 3 in the case 2 will be described with reference to FIGS.
FIG. 5 is a view showing the outer shape of the previous stage in which the derivative component 3 is accommodated in the case 2. FIG. 6 is a perspective view showing details of the inner bottom surface of the case 2. FIG. 7 is a cross-sectional view illustrating the positional relationship between the inside of the case 2 and the magnetic core 7 as viewed from above the open surface of the case 2.
In the case 2, the internal space is a substantially rectangular parallelepiped, the upper surface is an open surface, the remaining five surfaces are surrounded by the side wall 21 and the bottom 22, and the derivative component 3 is accommodated in the enclosed interior. The bottom 22 of the case 2 has a shape that is processed so that opposing sides are expanded outward and attached to the heat sink 11 by screw fastening or the like.
The surface opposite to the open surface of the case 2, that is, the back surface of the inner bottom surface of the case 2 is flat and is in contact with the heat sink 11, and the heat generated by the derivative component 3 mainly passes through the bottom 22 from the inner bottom surface. Heat is dissipated to the heat sink 11. Hereinafter, the back surface of the inner bottom surface of the bottom 22 of the case 2 is referred to as a first surface.

  Overhanging portions 23 a and 23 b are formed vertically in the center in the width direction of the pair of side walls 21 facing the case 2. The protruding portion 55a of the insulating bobbin 5a of the derivative component 3 is fastened to the overhang portion 23a by a screw (not shown). Further, the protruding portion 55b of the insulating bobbin 5b of the derivative component 3 is fastened to the overhang portion 23b by a screw (not shown).

Here, the surface used in the explanation of the inner bottom surface is defined. The cylinder taken up in the following description has the same radius as the radius of the winding part 62 of the coil 6 or twice the radius of the winding part 62 of the coil 6.
Of surfaces obtained by cutting a side surface of a cylinder with a cutting plane obtained by moving a plane including the axis of the cylinder in the radial direction of the cylinder, a surface opposite to the axis with respect to the cutting plane is referred to as a cylindrical peripheral surface. The axis of the original cylinder is referred to as the axis of the cylindrical peripheral surface, and the radius of the original cylinder is referred to as the radius of the cylindrical peripheral surface.

As shown in FIG. 6, the inner bottom surface of the case 2 has a second surface region sf2 that is rectangular when the inner bottom surface is viewed from the top, and a first surface region sf1 that has a square shape surrounding the second surface region sf2. And can be divided into two areas. The first surface region sf1 is formed from a flat surface, whereas the second surface region sf2 has a cylindrical peripheral surface disposed so that the axis overlaps a line passing through the overhanging portions 23a and 23b. The cylindrical peripheral surface holds the winding peripheral edge of the winding portion 62 of the coil 6 when the axis of the coil 6 is aligned with the axis of the cylindrical peripheral surface.
And since the lowest line among the lines parallel to the axis of the cylindrical peripheral surface of the second surface region sf2 is higher than the plane of the first surface region sf1, the second surface region sf2 is above the first surface region sf1. Protruding. Therefore, the first protrusion is provided in the second surface region sf2.

  When the coil 6 is placed on the circumferential surface of the cylinder 6 so that the axis of the coil 6 overlaps with the axis of the circumferential surface of the cylindrical surface, the most of the lines parallel to the axis of the winding circumference of the winding portion 62 of the coil 6 is the most. The lower line is aligned at the same position as the lowest line among the lines parallel to the axis of the cylindrical peripheral surface. That is, this overlapping line becomes a positioning base point, and the peripheral edge of the cylinder extends over a half or a quarter of the winding circumference of the winding circumference of the winding portion 62 of the coil 6 with the positioning base point as the center. Held by the surface.

As described above, the first surface portion having the cylindrical peripheral surface formed on the second surface region sf2 is provided, and the winding peripheral edge of the winding portion 62 of the coil 6 is in contact with the cylindrical peripheral surface. Since the gap between the coil 2 and the coil 6 is reduced, the cooling function of the coil 6 can be improved, and the reactor device 1 can be downsized.
Regardless of the size of the coil 6, the first protrusion of the second surface region sf2 has a cylindrical peripheral surface, so that the weight of the coil 6 itself fits in the center of the case, thereby improving productivity.

  Although not shown and described, the coil 6 may be supported by providing second protrusions on both sides of the first protrusion.

When the inner bottom surface of the case 2 is viewed from above the open surface of the case 2 and the magnetic core 7 is projected on the inner bottom surface inside the case 2, the result is as shown in FIG.
In FIG. 7, the outer peripheral shape of the magnetic core 7 becomes a mouth shape by the outer leg 73 a and the side end 74 a of the magnetic core 7 a and the outer leg 73 b and the side end 74 b of the magnetic core 7 b. The columnar portion 72a of the magnetic core 7a and the columnar portion 72b of the magnetic core 7b are present on the inner side surrounded by the outer periphery of the square shape, and the center axis 6c of the coil 6 and the centers of the columnar portions 72a and 72b of the magnetic core 7 are present. The line is positioned so as to substantially overlap the line connecting the centers of the screw holes formed at the upper ends of the overhang portions 23 a and 23 b of the side wall 21 of the case 2.

  In FIG. 7, the magnetic core 7 whose outer peripheral shape is in the shape of a letter is located at the center in the horizontal direction and the vertical direction in the figure relative to the side wall 21 of the case 2. The distances, that is, the gaps in which the mold resin 4 is filled outside the magnetic core 7 having a letter shape are substantially equal distances in the horizontal direction and the vertical direction in the drawing. For this reason, when heat is transferred from the mouthpiece-shaped magnetic core 7 to the side wall 21 via the mold resin 4, unevenness and variation are reduced.

The cylindrical peripheral surface having a height difference from the inner bottom surface of the case 2 is arranged so that the axis of the cylindrical peripheral surface overlaps a line obtained by projecting the central axis 6c of the coil 6 onto the inner bottom surface. The shape of the circumferential surface of the cylinder coincides with the shape obtained by adding the thickness of the insulating member 9 interposed between the circumferential edges of the winding portion 62 of the coil 6.
That is, the lowermost part of the winding circle periphery of the winding part 62 of the coil 6 is located at the lowest position in the height difference of the cylindrical peripheral surface formed in the second surface region sf2 of the inner bottom surface of the case 2. 9 is positioned and arranged.

The cylindrical tubular portions 52a and 52b of the insulating bobbins 5a and 5b are disposed so as to be fitted inside the coil 6, and the insulating bobbins 5a and 5b are abutted to each other so that the fitting portions of the tubular portions 52a and 52b are fitted. 52c is fitted.
Further, the columnar portions 72a and 72b of the magnetic cores 7a and 7b are fitted and inserted into the cylindrical portions 52a and 52b of the insulating bobbins 5a and 5b.
For this reason, when housing the derivative component 3 in the case 2, the protruding portion 55a of the insulating bobbin 5a in the derivative component 3 is screwed to the overhanging portion 23a of the side wall 21 of the case 2, and the protruding portion of the insulating bobbin 5b. Positioning between the magnetic core 7 and the case 2 is achieved by screwing 55b to the overhanging portion 23b of the side wall 21 of the case 2.

  As described above, the coil 6, the insulating bobbin 5, and the magnetic core 7 are positioned inside the case 2 and the arrangement shown in FIG. 7 is obtained. The positioning described above is effective when a small-sized and small size is constructed as the in-vehicle reactor device 1 and it is necessary to consider insulation for handling a high voltage. .

A typical failure factor of the reactor device 1 is that desired insulation resistance cannot be obtained, but in order to ensure sufficient insulation resistance and reduce product defects and failures, it matches the desired insulation voltage. Thus, it is desirable to secure a distance (insulation distance) between parts that require insulation.
However, if the distance is ensured excessively, it conflicts with the request to make the reactor device 1 small. For this reason, it is desirable to arrange the components constituting the reactor device 1 with the minimum necessary insulation distance, but if the component arrangement varies in the process of assembling the reactor device 1, it does not have the desired insulation resistance. There is a risk of producing defective products.
However, with the positioning mechanism of the present invention, the reactor apparatus 1 having a desired insulation resistance can be manufactured in a short time with easy workability without a shortage of insulation distance due to variations and with a small size and small dimensions. it can.

Further, regarding the reactor device 1 in which the insulating bobbin 5 is fastened to the case 2 with screws, the mold resin 4 is filled into the case 2 and the coil 6, the magnetic core 7, the insulating bobbin 5, and the insulating member 9 are immersed. Yes.
Here, the insulation between the winding portion 62 of the coil 6 and the outer leg portion 73a of the magnetic core 7a and the outer leg portion 73b of the magnetic core 7b is determined by the solid structure of the insulating bobbin 5 and the insulating member 9. It is ensured not to be an insulating material but to be arranged so as to be separated by a distance that does not cause dielectric breakdown even in the air. Here, the insulation between the winding part 62 and the outer leg part 73a and the outer leg part 73b may be made dependent on the insulating property of the mold resin 4 but the mold resin 4 is not sufficiently filled. Insulation distance is set on the assumption of failure such as deterioration of insulation resistance due to mixing of bubbles due to bubbles or cracks.

Next, the magnetic flux generated inside and outside the magnetic core 7 will be described.
8 and 9 are diagrams showing the magnetic flux of the magnetic core 7 of the dielectric component 3. FIG.
FIG. 8 shows the magnetic flux when there is a gap between the columnar portions 72a and 72b of the magnetic core 7, and FIG. 9 shows the magnetic flux in the core gap on the outer periphery between the outer legs 73a and 73b of the magnetic core 7. . These magnetic fluxes are shown as magnetic fluxes when radiated without being disturbed by other parts, and the magnetic fluxes of FIGS. 8 and 9 are radiated simultaneously. 8 and 9, the magnetic flux trajectory is not limited to this when there is an overlap or interference from other parts.

As shown in FIG. 8, when there is a gap between the end surface of the columnar portion 72a and the end surface of the columnar portion 72b of the magnetic core 7, the gap sandwiched between the end surface of the columnar portion 72a and the end surface of the columnar portion 72b As in the case of the magnetic flux 80b, the light is radiated substantially perpendicularly from the end surface of the columnar portion 72a and is incident substantially perpendicularly on the end surface of the columnar portion 72b.
Further, the magnetic flux leaking from the columnar portions 72a and 72b is drawn from the columnar portion 72a while drawing a large arc such as the magnetic flux 80a as the distance from the closest part of the columnar portions 72a and 72b increases. Is done.

As shown in FIG. 9, when there is a gap between the end surface of the outer leg portion 73a and the end surface of the outer leg portion 73b of the magnetic core 7, it is sandwiched between the end surface of the outer leg portion 73a and the end surface of the outer leg portion 73b. In such a gap, like the magnetic flux 81b, the light is radiated from the end surface of the outer leg portion 73a substantially perpendicularly and is incident on the end surface of the outer leg portion 73b substantially perpendicularly.
Further, the magnetic flux leaking from the outer leg portions 73a and 73b is drawn from the outer leg portion 73a while drawing a large arc like the magnetic flux 81a as the distance from the closest point of the outer leg portion 73a and the outer leg portion 73b increases. The light enters the leg 73b.

  In this phenomenon, when the magnetic flux density in the vicinity of the gap increases, the magnetic flux emitted from the magnetic core 7 at a position far from the gap increases, and the emitted magnetic flux has a larger angle with respect to the gap direction. Can be explained.

As for the magnetic flux generated in the gap passing through the central axis 6c in FIG. 8, the leakage magnetic flux passes through the wound coil 6 and is absorbed. Further, the magnetic flux in the magnetic field transmitted through the coil 6 and radiated to the outside is absorbed by the second surface region sf <b> 2 of the case 2 and the magnetic core 7. The magnetic flux passing through the center on the core cylinder axis returns to the core cylinder axis while drawing the largest circular magnetic flux 80a.
At this time, since the overhang portions 23a and 23b for case screw fastening are on this axis, all of them can be absorbed without passing through the overhang portions 23a and 23b for case 2 screw fastening. What is radiated to the upper outside of the coil 6 is radiated to the space, but since there is no obstructing conductor or the like, the magnetic flux returns to the pair of magnetic cores 7.

As shown in FIG. 9, the gap of the magnetic core 7 occurs not only at the positions where the end surfaces of the columnar portions 72a and 72b face each other but also at all the adjacent positions 8g of the magnetic path of the magnetic core 7, so that the coil 6 is wound. It can be said that the same phenomenon occurs in the flow of magnetic flux not only at the columnar portions 72a and 72b but also at the closest point where the end surfaces of the outer leg portions 73a and 73b face each other on the outer periphery of the magnetic core 7.
Since there is no conductor portion such as the coil 6, the amount of magnetic flux that strikes the inner side surface of the case 2 increases at the closest magnetic flux. However, at this closest location, the magnetic flux is not radiated on the outer peripheral wall axis, and it can be assumed that there is almost no heat generation due to the leakage magnetic flux at the four corners of the case 2.

Next, the gaps at the outer legs 73a and 73b and the magnetic flux at the inner periphery of the case 2 will be described in detail with reference to FIG.
Regarding the magnetic field generated in the gap, when the absorber is a conductor, reflection and refraction occur on the inner surface of the case 2. At this time, the magnetic flux is deflected near the inner surface of the case 2 without moving to the magnetic core 7 facing the gap by the same distance in a parabolic manner, and the magnetic flux is deflected near the inner surface of the case 2. Disappearance occurs.
About the heat generated by the generation of eddy current inside the case due to the magnetic flux incident on the inner peripheral surface of the case 2, the heat is generated only on the inner peripheral surface due to the thickness of the case 2, and the influence on the periphery of the case 2 and other peripheral electronic devices Can be minimized.

  By disposing the protrusion of the case 2 in the center of the case 2, the distance between the case 2 wall surface and the reactor magnetic core 7 is constant with respect to electromagnetic waves caused by leakage magnetic flux generated in the magnetic core gap of the reactor in the case 2. Therefore, the electromagnetic wave generated outside the magnetic core 7 is reflected by the case 2 and is less likely to concentrate on a certain point.

  Projections such as positioning on the outer peripheral surface of the magnetic core 7 and the inner peripheral surface of the case 2 are not attached to the case 2, and the leakage magnetic flux in the gap of the magnetic core 7 is close to the magnetic core 7. Since the angle of the magnetic flux radiated into the air is small with respect to the gap direction, if the distance from the case 2 is sufficiently secured, both the heat generation and the magnetic characteristics will hardly change from those in the air. .

However, when the magnetic flux density near the gap increases, the magnetic flux emitted from the magnetic core 7 far from the gap increases, and the emitted magnetic flux has a larger angle with respect to the gap direction. Regarding the generated magnetic field, reflection and refraction occur on the inner surface of the case 2.
At this time, the direction of the magnetic flux does not move by the same distance in a parabolic manner to the core facing the gap, but the magnetic flux deflected near the inner surface of the case 2 increases, and the magnetic flux is attenuated and extinguished. .
At this time, as described above, the generation of eddy current in the conductor portion due to the magnetic flux incident in the metal conductor such as the case 2 generates heat in the metal conductor near the magnetic core gap, so the magnetic core 7 is positioned. In the case where such a protrusion is provided, the magnetic flux is blocked at the protrusion portion, so that deterioration of magnetic characteristics and concentration of heat generation due to eddy current due to the magnetic field occurs at the protrusion portion.

  In addition, with respect to the above phenomenon, the magnetic flux in the vicinity of the gap does not return to the paired magnetic core 7, and the magnetic flux density changes, so that the inductance is reduced when inserted into the case 2. The closer the magnetic core gap is to the wall surface of the case 2, the more the magnetic flux is biased, and the heat generation on the inner surface of the case 2 and the deterioration of the magnetic characteristics become remarkable.

  With respect to the above phenomenon, providing a protrusion on the inner surface of the case 2 that does not follow the outer peripheral side surface of the magnetic core 7 acts to hinder the direction of the magnetic flux generated in the gap, thereby improving the magnetic characteristics of the reactor. Therefore, it can be said that the case 2 in the form along the outer peripheral side surface of the magnetic core 7 is the best.

Further, since the distance between the magnetic core 7 and the case 2 is kept constant, eddy currents are induced by the electromagnetic waves absorbed by the case 2 to generate heat, but the wall surface of the case 2 paired with the magnetic core 7 The distribution of the hot part is uniform.
For this reason, variation in the generation of radiant heat is reduced, and the amount of radiant heat can be suppressed.
Moreover, even if an electronic component is disposed in the vicinity of the reactor, the degree of temperature rise of the electronic component can be reduced and densely arranged, and an electric device using the reactor can be reduced in size.

  In addition, the magnetic field of the reactor can be specified because the region where the phenomenon occurs is widely dispersed and the region where the magnetic properties change can be specified in the part where the electromagnetic wave due to its own magnetic flux and reflection is amplified or the part where the magnetic flux decreases due to cancellation. The characteristics can be constant without individual variation.

Next, the magnetic flux at the columnar protrusion will be described in detail with reference to FIG.
The leakage magnetic flux generated in the gap of the magnetic core 7 of the reactor in the case 2 is absorbed in the second surface region sf2 that forms the columnar peripheral surface, and the phenomenon that the magnetic characteristics of the reactor are deteriorated is also described above. The phenomenon corresponds to the columnar portions 72a and 72b of the magnetic core 7 and the coil 6 which is a conductor, and the second surface region sf2 where the columnar portions 72a and 72b of the magnetic core 7 and the columnar peripheral surface are formed.

  A coil 6 wound along the columnar shapes of the columnar portions 72a and 72b of the magnetic core 7 and a columnar peripheral surface formed so as to hold the outer circumference of the wound coil 6 are formed. In addition, since the second surface region sf2 is present, the magnetic field generated in the gap between the columnar portions 72a and 72b and the magnetic field generated in the gap between the outer leg portions 73a and 73b are less affected, and the gap between the magnetic cores 7 is mutually reduced. Due to the change in magnetic flux in the periphery, eddy currents are not generated in the counterpart magnetic core 7 and no heat is generated. Therefore, magnetic saturation due to temperature characteristics in the magnetic core 7 does not occur, and the reactor obtains stable magnetic characteristics. be able to.

  The coil 6 wound along the columnar shape of the magnetic core 7 and the second surface region sf2 formed with the columnar peripheral surface provided so as to hold the outer circumference of the wound coil 6. With respect to the shape of the magnetic core 7, there is little bias of heat generation in the case 2 part of the leakage magnetic flux of the magnetic core 7, and the tendency to decrease the magnetic characteristics can be intentionally controlled, thereby suppressing variations in magnetic characteristics and reducing heat generation. It is possible.

Further, as described above, since this protrusion is also shaped to follow the shape of the magnetic core 7, the distance between all the magnetic cores 7 and the case 2 can be kept constant, the heat generation is made uniform, Stabilization of magnetic properties can be obtained.
At this time, since the cooling surface to which the case 2 is attached is below and the positioning protrusion is provided integrally with the case, it is possible to sufficiently dissipate heat even if heat is generated at the protrusion. .
In addition, by having the protrusions in the case columnar peripheral recesses, the distance between the inner surface of the core and the protrusions in the columnar peripheral recesses can be reduced, and the cooling function of the core can be improved. Is possible.

  Since this phenomenon is due to leakage magnetic flux in the magnetic core gap, with respect to the magnetic core 7 made of a dust core formed by forming magnetic powder, magnetic flux cancellation and inductance value change due to strengthening are reduced. Therefore, it can be said that it is more effective.

  In addition, by holding the first protrusion that forms the columnar peripheral surface at a position higher than the lower end surface of the magnetic core 7 and by setting the height of the outer peripheral wall surface of the case 2, Thus, it is possible to easily set how much leakage magnetic flux generated is not generated outside the device.

  Further, the projecting portions 23a and 23b for providing the screw holes for fixing the bobbin screw pass through the center of the reactor columnar axial direction, and are disposed integrally with the outer peripheral side surface of the case 2 so as to be perpendicular to the case 2, thereby extending the columnar portion in the axial direction. Magnetic flux radiated through the magnetic core 7 can be shielded by the thicker case 2.

  Since the magnetic flux generated through the magnetic core 7 at the cylindrical axis of the magnetic core 7 is radiated in the upward direction of the reactor cylindrical axis, it becomes the maximum magnetic path length in the air of the magnetic flux in the reactor. In order to eliminate the influence on other peripheral devices, the thick case 2 can be shielded in all cases 2.

  Insulating bobbin that positions and locks the winding portion 62 of the coil 6 between the inner side surface of the coil 6 in which the conductor winding is wound in a substantially cylindrical shape and the side surfaces of the columnar portions 72a and 72b of the magnetic core 7. 5a, 5b, on the other hand, because the lower part of the outer surface of the winding part 62 of the coil 6 is held by the columnar peripheral surface of the second surface region sf2 via the sheet-like insulating member 9, Even when the magnetic core 7 is made of a dust material, the contact at the contact portion between the magnetic core 7 and the case 2 due to vibration is prevented more than when the magnetic core 7 is directly held by the protrusions and surfaces of the case 2. be able to.

  Even if the lower end surface of the magnetic core 7 is in contact with the first surface region sf1 on the lower bottom surface of the case 2, the entire lower end surface in contact with the first surface region sf1 is in contact with the weight of the magnetic core 7. As a result, the magnetic core 7 can be prevented from being broken.

Since the reactor device 1 according to the first embodiment of the present invention can dissipate heat generated in the gap existing in the magnetic core 7 and efficiently cool the reactor device 1, the downsizing of the high-current, high-voltage reactor device is reduced. It becomes possible.
Further, the coil 6 and the magnetic core 7 wound around the coil 6 and the core gap are arranged at the center of the entire product to concentrate the heat generation at the center and keep away from the outer surface of the case 2 to withstand high temperatures. If it is made of a structural member, the instantaneous rating can be improved, and the propagation of radiant heat to peripheral parts can be reduced, so that the entire product can be downsized.

In addition, since the radiation of electromagnetic waves to the outside of the case 2 is suppressed and the radiant heat from the derivative component 3 is also suppressed, it is possible to reduce the influence on the peripheral electronic components and reduce the size of the electric device. It is possible to contribute to higher density and higher density.
For this reason, the reactor apparatus 1 suitable for using for the power converter for powertrains of electric vehicles, such as a hybrid vehicle and an electric vehicle in which high fuel efficiency performance is calculated | required, is obtained.

  DESCRIPTION OF SYMBOLS 1 Reactor apparatus, 2 Case, 3 Derivative parts, 4 Mold resin, 5, 5a, 5b Insulating bobbin, 6 Coil, 6c Center axis, 7, 7a, 7b Magnetic body core, 9 Insulating member, 11 Heat sink, 21 Side wall, 22 Bottom, 23a, 23b Overhang, 52a, 52b Tubular, 52c Fitting, 53a, 53b Flat, 54 Protrusion, 55a, 55b Protrusion, 56a, 56b Protrusion, 57 Terminal block, 61a, 61b Terminal , 62 Winding part, 72a, 72b Columnar part, 73a, 73b Outer leg part, 74a, 74b Side end part, 80a, 80b, 81a, 81b Magnetic flux, G Magnetic gap, sf1 First surface area, sf2 Second surface area .

Claims (5)

A reactor device having a case, a derivative component housed in the case, and a mold resin filled in a gap formed by the derivative component and the case,
The derivative parts are
A core that forms a magnetic path inside as a magnetic material;
A coil in which a conductor winding is wound in a substantially cylindrical shape;
An insulating bobbin that positions and locks the winding portion of the coil on the columnar portion of the core;
A sheet-like insulating member that insulates between the winding portion of the coil and the case;
The insulating bobbin is divided into a pair of cylindrical tubular portions that are fitted and inserted along the shaft inside the coil from both ends in the axial direction of the coil. Consisting of insulated bobbins,
The core has a cylindrical shape of the insulating bobbin along the axis from the center of the surface side where the flat portion of the insulating bobbin at the side end contacts from the outside of the insulating bobbin on both ends in the axial direction of the coil. A pair of divided magnetic bodies each having a cylindrical columnar portion that is inserted and inserted into the portion and an outer leg portion that extends from both ends of the side end portion along the outside of the coil protrudes in the same direction. Consisting of the core,
The coil, a set of divided insulating bobbins, and a set of divided magnetic cores are integrated and accommodated in the case,
The case has a concave cylindrical peripheral surface formed at a substantially center of the inner bottom surface with the same radius as the radius of the coil winding portion or twice the radius of the coil winding portion. A first protrusion is provided;
The derivative component is positioned and held by placing the winding portion of the coil on the cylindrical peripheral surface of the case via the sheet-like insulating member, and at both ends of the coil in the axial direction. And each of the divided insulating bobbins is fixed to the case.
A reactor device characterized by that. The winding portion of the coil uses a line segment of the outer surface that is in contact with the outer surface of the winding portion of the coil, the axis of which is disposed horizontally, as a positioning base point, which is in contact with the horizontal surface raised from below. It is hold | maintained by the said 1st projection part over the area | region of a winding circumference half or a quarter. The reactor apparatus of Claim 1 characterized by the above-mentioned. The above case
Second protrusions are provided at both ends of the first protrusion,
The winding portion of the coil is positioned by the first protrusion and the second protrusion, and is raised from the lower side to the outer surface of the winding portion of the coil in which the shaft is disposed horizontally. The line segment of the outer surface that is in contact with the horizontal plane is used as a positioning base point, and is held by the first protrusion over an area of ¼ or less of the winding circumference. Item 2. The reactor device according to Item 1. The lower end surface of the core is in contact with the inner bottom surface of the case,
The winding portion of the coil is held by the protrusion at a surface height higher than a contact surface with the lower end surface of the core among a plurality of surfaces having different surface heights on the inner bottom surface of the case. The reactor apparatus in any one of Claims 1 thru | or 3 characterized by the above-mentioned. The opposing tip portions of the cylindrical portions of the set of divided insulating bobbins are fitted together,
When the leading ends of the outer leg portions of the set of divided magnetic cores face each other and are fixed by fixing means, and there is a magnetic gap between the facing tip portions of the columnar portions, the above A non-magnetic material is provided in the region that becomes the magnetic gap.
The reactor apparatus in any one of Claims 1 thru | or 4 characterized by the above-mentioned.

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