JP2008028290A - Reactor device and assembly method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reactor device having a high heat radiation function inexpensively as much as possible. <P>SOLUTION: The reactor device A has a reactor B having a core 1 and a coil 2, and a case 3. The core 1 has: a side part core 12; a middle part core 10; and a gap spacer 11. The coil 2 includes: two annular parts 21 laminated while being wound spirally so that space in a prism shape is surrounded; a connection section 22 for connecting the annular sections 21; and terminals 23 at both ends projecting upward. A resin layer 30 for radiating heat having high thermal conductivity is provided at a region from the corner section at the upper side of the center of each annular section 21 of the coil 2 to the inner surface of the case 3. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention mainly relates to a heat dissipation measure for a reactor mounted on a fuel cell vehicle or a hybrid vehicle.

  In recent years, automobiles that drive motors with a DC power source such as hybrid vehicles and fuel cell vehicles have been developed due to environmental problems. A booster circuit disposed in a fuel cell vehicle or a hybrid vehicle includes a reactor device for increasing the efficiency of voltage conversion.

  Generally, as disclosed in Patent Document 1, a reactor device is configured by housing a reactor including a core and a coil wound around the core in a case. A reactor device mounted on a hybrid vehicle or the like is arranged for improving the power factor at the time of conversion of a high-frequency signal with a high frequency of about 10 kHz, and the coil and the core generate a large amount of heat. Therefore, as disclosed in Patent Document 1, the case in which the reactor is accommodated is filled with a heat-dissipating resin (potting resin) containing a filler, and heat is released from the heat-dissipating resin to the case connected to the heat sink. Is known.

JP 2005-72198 A

  With the technique of the above-mentioned patent document 1, heat of the coil or core can be radiated to the case side via the potting resin. However, since a large amount of resin such as epoxy resin is filled in the case, the cost is considerably high. However, according to the inventor's verification test, it has been found that the temperature rise is not uniform in each part of the coil and there is considerable variation.

  An object of the present invention is to provide a reactor device that can reduce the manufacturing cost while securing a necessary heat radiation amount by adopting an appropriate heat radiation structure in consideration of the temperature distribution in the reactor.

  The reactor device of the present invention supports and accommodates the core and the coil, and in a case connected to the heat radiating member, from the specific region of the annular portion wound around the core coating region, other than the core coating region A heat-dissipating resin layer is provided on the region reaching the part.

  Thus, if the high temperature region is selected as the specific region of the annular portion in consideration of the temperature distribution in the reactor, a heat dissipation path that leads from the specific region of the annular portion to the external heat dissipation member through the case is formed. Therefore, a desired heat dissipation function can be ensured. In addition, compared to filling the case with potting resin, the amount of heat-dissipating resin is drastically reduced, and the manufacturing cost can be reduced.

  Since the specific region in which the heat-dissipating resin layer is formed in the annular portion of the coil includes the maximum temperature region, the heat dissipation efficiency is improved.

  When the core has a track shape consisting of a straight portion and a curved portion that become the coating region, the temperature rise near the upper corner portion of the center portion of each annular portion of the coil is the largest, so that the heat radiation resin from this specific region The layer should just be formed.

  Since the heat radiation resin layer is formed on the regions reaching the curved portions on both sides of the core, the heat radiation function is further improved.

  In order to further improve the heat dissipation function, it is preferable that the heat dissipation resin layer reaches the inner surface of the case.

  Since the heat dissipation resin layer is made of an epoxy resin containing a metal filler, it is possible to reduce the manufacturing cost while ensuring the heat dissipation function.

  In addition to the process of assembling the core and the coil, the process of housing the core and the coil in the case, the method for manufacturing the reactor device of the present invention includes a resin on a region that reaches a portion other than the coating region of the core from the specific region of the coil. Is included to form a heat-dissipating resin layer.

  This method not only reduces the amount of resin used, but also reduces the manufacturing cost by shortening the time for curing the resin, compared to the assembly method in which the case is filled with potting resin. it can.

  When the heat-dissipating resin layer is formed so as to reach the inner surface of the case, the resin is supplied after the core and the coil are accommodated in the case.

  When forming the heat-dissipating resin layer partway through the core, the step of forming the heat-dissipating resin layer may be before or after the step of housing the core and the coil in the case.

  By using an epoxy resin containing a metal filler as the resin when forming the heat dissipation resin, a heat dissipation resin layer having a high heat dissipation function can be formed at low cost.

  According to the reactor device or the manufacturing method thereof of the present invention, instead of filling the potting resin in the case, the heat radiation resin layer is formed on a part of the core from a specific region of the coil, so that the heat radiation function is maintained high. However, the manufacturing cost can be reduced.

(Embodiment)
-Structure of the reactor device-
FIG. 1 is a perspective view of a reactor device A according to an embodiment. As shown in FIG. 1, the reactor device A includes a core 1, a coil 2 that surrounds the periphery of the core 1 in an annular shape, a middle case 4 that houses the core 1, the coil 2, and the like, and a case 3 that houses the whole. I have. The reactor B includes a core 1 and a coil 2 surrounding the core 1 in an annular shape. The coil 2 includes two annular portions 21 that are spirally wound so as to surround a prismatic space, a connection portion 22 that connects the annular portions 21, and terminals 23 that protrude upward from both ends. Has been. The coil 2 is almost entirely covered with an insulating film, and only a pair of terminals 23 are exposed from the insulating film. The coil 2 is integrated by connecting two annular portions 21 at a connection portion 22, and when energized, an alternating current flows from one terminal 23 to the other terminal 23 sequentially through the two annular portions 22. .

  Further, in the region extending from the upper corner portion of each annular portion 21 of the coil 2 to the inner side surface of the case 3 through the curved portion Rb of the side portion core 12, a heat radiation resin layer 30 having high thermal conductivity is provided. Is provided.

  FIG. 2 is a perspective view showing the core 1 extracted from the reactor B in the embodiment. As shown in FIG. 2, the core 1 has a substantially track shape in plan view, and includes two straight portions Ra and curved portions Rb that connect the straight portions Ra at both ends of the two straight portions Ra. Have. Further, the core 1 includes a side partial core 12 extending over each end of the two linear portions Ra and the curved portion Rb, and intermediate partial cores 10 and gap spacers alternately arranged between the side partial cores 12 in each linear portion Ra. 11. Further, as shown in FIG. 4 to be described later, each linear portion Ra of the core 1 is covered with an inner bobbin 13 made of resin, and the coil 2 is wound around the outer side of the inner bobbin 13. It has become. And since each annular part 21 of the coil 2 is wound around each linear part Ra of the core 1, each linear part Ra is a covering area | region covered with the annular part 21 of the coil 2, and each curve The portion Rb is a portion other than the covering region exposed outside the coil. Further, both ends of the coil 2 are sandwiched by the outer bobbin 15, and the side partial core 12 of the core 1 is in a state of being exposed to the outside through the opening of the outer bobbin 15.

  That is, the core 1 and the coil 2 of the present embodiment have a structure suitable for a reactor for reducing a load during conversion between AC and DC in a high current and high frequency region, and are mounted on a hybrid vehicle or the like. Is. In this track-shaped reactor B, if the vicinity of the center line that divides the track in the vertical direction is the central portion, the covering region (straight line portion Ra) of the core 1 in a state where the heat-dissipating resin layer is not formed. Of the annular portion 21 of the coil 2 wound around the periphery of the coil 2, it is known that the upper corner portion of the central portion is the highest temperature region.

-Material of each part of reactor device-
Each of the side partial cores 12 and the intermediate partial core 10 of the core 1 is made of a soft magnetic material also called a high magnetic permeability material. Examples of soft magnetic materials include pure iron, soft iron, magnetic steel, silicon steel, permalloy, sendust, ferrite, and amorphous materials of magnetic alloys. A reactor that requires high frequency and high power, such as for driving an engine of a hybrid vehicle, is required to have a small iron loss in a frequency region of 1 kHz or higher. Moreover, in order to suppress vibration, it is preferable that the magnetostriction of the core 1 is small. As a soft magnetic material that meets such conditions, among non-oriented silicon steel plates, an unstrained silicon steel plate having about 6% silicon is frequently used because the magnetostriction is close to zero. However, this unstrained silicon steel sheet is expensive because it is expensive to manufacture.

  On the other hand, in the present embodiment, each of the side partial cores 12 and the intermediate partial core 10 of the core 1 is made of a sintered soft magnetic material. In this embodiment, as a sintered soft magnetic material, iron-based soft magnetic powder produced by an atomization method is surface-coated with a phosphate insulating coating and a resin binder, and the surface-coated powder is press-molded and then sintered at a high temperature. The result is used. This material has low holding power characteristics and is less expensive than unstrained silicon steel sheets.

  The gap spacer 11 is made of a nonmagnetic and insulating material such as ceramics, glass, or a glass epoxy substrate. The gap spacer 11 is a member necessary for adjusting the inductance according to the frequency. In addition, since the total thickness of the gap spacers 11 required for the core 1 as a whole is determined by design, the number of gap spacers 11 is set so that the thickness of one gap spacer 11 does not cause excessive leakage current. It has been established. In the present embodiment, the gap spacer 11 has a thickness of about 1.31 μm, the adhesive layer has a thickness of about 0.02 μm, and the size of each gap is set to 1.35 μm.

  The case 3 is made of a material having good thermal conductivity such as Cu or Cu alloy, aluminum or aluminum alloy, and is configured to release heat generated in the reactor B outward from the case 3. Yes.

  In this embodiment, the heat radiation resin layer 30 is generally made of an epoxy resin containing a metal filler, and has a thermal conductivity of 0.5 to 20 (W / m · K). As the resin constituting the heat radiation resin layer 30, for example, an epoxy resin filled with aluminum, aluminum nitride or the like can be used, and as a commercially available resin material, for example, trade name Alecom Co., Ltd. There are bonds 568, 805, and 860. The thermal conductivities of Alecom Bonds 568, 805, and 860 are 15.6 (W / m · K), 21.6 (W / m · K), and 14.7 (W / m · K), respectively. It is suitable as a material for the heat radiation resin layer 30 of the present invention.

  The reactor device A of the present embodiment extends from the upper corner portion of the annular portion 21 of the coil 2 to the heat radiation resin layer 30-case 3 (and the heat radiation resin layer 30-side partial core 12-case 3). The feature is that a heat dissipation path is formed. As described above, the upper corner portion of the annular portion 21 of the coil 2 is the highest temperature region of the coil 2. However, the maximum temperature region refers to a region where the temperature is highest in a state where the heat-dissipating resin layer is not formed. Thus, by providing a heat dissipation path from the upper corner of the central portion, which is the highest temperature region of the coil 3, to the case 3, compared to the conventional structure in which the entire gap in the case 3 is filled with the heat dissipation resin. Thus, effective heat dissipation can be performed with a small amount of resin used, and the manufacturing cost can be reduced.

  The heat-dissipating resin layer 30 may be formed over the upper and lower corner portions of the center portion of the annular portion 21 of the coil 2. As shown in FIG. 5, the corner portion below the central portion of the annular portion 21 is not in the maximum temperature region, and is close to the case 3 so that the heat dissipation is relatively good. Because it reaches

-Assembly procedure of reactor device A-
FIG. 3 is a perspective view for explaining a procedure for housing the reactor B in the middle case 4. FIG. 4 is a partially cutaway perspective view showing the state when the reactor B is stored in the middle case 4. The assembly procedure from the state shown in FIG. 3 to the state shown in FIG. 4 is as follows. First, the intermediate partial core 10 and the gap spacer 11 are bonded together, and then covered with the inner bobbin 13. Thereafter, an assembly of the inner bobbin 13, the gap spacer 11, and each intermediate partial core 10 is fitted into a space surrounded by each annular portion 21 of the coil 2. At this time, the gap spacers 11 at both ends are exposed to the space in the annular portion 21 of the coil 2. Next, the two side partial cores 12 are attached so as to straddle the gap spacers 11 exposed at both ends of the assembly. Thereby, the assembly shown to the center part of FIG. 3 is assembled. Further, a closed annular core 1 is completed. Thereby, the reactor B is formed. Thereafter, as shown in FIG. 5, an outer bobbin 15 for fixing the side partial core 12 and the coil 2 to each other is attached, and the whole is stored in the middle case 4, and the reactor B accommodated in the middle case 4 is placed in the case 3 Store in.

  FIG. 5 is a cross-sectional view schematically showing a state where the final assembly of the reactor device A is completed. However, in FIG. 5, illustration of members such as the middle case 4 which are not main members is omitted. As shown in FIG. 5, a recess for receiving the coil 2 of the reactor B is provided on the bottom surface of the inner surface of the case 3, and the core 1 (side partial core 12) of the reactor B is the bottom surface of the inner surface of the case 3. Is supported in contact with. Although not shown, the case 3 is installed on the heat sink, and the heat generated in the reactor B is efficiently radiated from the case 3 to the heat sink because the core 1 and the case 3 are in contact with each other.

  Thereafter, as shown in FIG. 5, a resin having a high thermal conductivity is applied to a region extending from the upper corner portion of the annular portion 21 of the coil 12 to the inner side surface of the case 3 through the side portion core 12 to dissipate heat. The resin layer 30 for forming is formed. At this time, the end portion of the one outer bobbin 15 in contact with the terminal 23 of the coil 2 extends above the annular portion 21 of the coil 2, so that the heat radiation resin layer 30 is formed on the inner surface of the one outer bobbin 15. To the inner surface of the case 3 beyond the other outer bobbin 15. Thereby, the reactor apparatus A shown in FIG. 1 is assembled.

  Here, the resin supply method includes extrusion from a nozzle, brush coating, spraying, and the like, and any method may be used.

  According to the assembly process of the present embodiment, the filling time and curing time of the resin are shortened as compared with the conventional case where the entire gap in the case 3 is filled with the heat radiation resin, so that the assembly time is also shortened. The Therefore, the manufacturing cost can be reduced by shortening the process.

(First modification)
FIG. 6 is a cross-sectional view of reactor device A1 according to the first modification of the above embodiment. In the above embodiment, the heat-dissipating resin layer 30 is formed so as to reach the inner side surface of the case 3, but in the present modification, it is formed only halfway along the side partial core 12 of the core 1. Even in such a structure, a heat dissipation path that connects the heat dissipation resin layer 30 through the side partial core 12 to the heat sink from the bottom surface of the case 3 is formed, so that the same heat dissipation effect as in the above embodiment is exhibited. be able to.

  In the process of assembling the reactor device of this modification, the heat-dissipating resin layer 30 may be formed in the state where the reactor B shown in FIG. 4 is assembled.

(Second modification)
Although illustration of this modification is omitted, in FIG. 5 or FIG. 6, a heat radiating resin layer 30 that reaches at least the side partial core 12 beyond the outer bobbins 15 on both sides may be formed. Such a structure can be easily realized, for example, by digging a portion between the two terminals 23 of the outer bobbin 15 on the side in contact with the terminals 23 and applying a resin. As a result, the heat dissipation function can be further improved.

  The structure of the embodiment of the present invention disclosed above is merely an example, and the scope of the present invention is not limited to the scope of these descriptions. The scope of the present invention is indicated by the description of the scope of claims, and further includes meanings equivalent to the description of the scope of claims and all modifications within the scope.

  In the above embodiment, the reactor device A including the track-shaped core 1 and the coil 2 having the two annular portions 21 has been described. However, the present invention has not only the track shape but also other shapes. It can be applied to one having a core and a coil. Even in that case, the manufacturing cost can be reduced by forming a heat radiation path from the maximum temperature region of the coil or the vicinity thereof to the case instead of filling the entire case with potting resin.

  In the above embodiment, the heat-dissipating resin layer 30 is formed on the entire upper corner portion of the annular portion 21 of the coil 2 on the assumption that the track-shaped core 1 is provided. It is not necessary for the heat radiation resin layer 30 to be provided on the entire upper corner portion of the portion 21. For example, even if there is a portion where the heat radiating resin layer is not formed in a part of the upper corner portion of the annular portion 21, the basic effect of the present invention can be obtained as long as it has a certain heat radiating function. it can.

  The reactor and the reactor device of the present invention can be used as a component such as a booster circuit in a hybrid vehicle, a fuel cell vehicle, and a factory / household power supply system.

It is a perspective view which shows schematic structure of the reactor apparatus in embodiment. It is a perspective view which shows the structure of the core in embodiment. It is a perspective view for demonstrating the procedure which accommodates a reactor in a middle case. It is a perspective view which shows the state of the reactor apparatus which accommodated the reactor in the inner case, partially fractured. It is sectional drawing which shows the state which the final assembly of the reactor apparatus was complete | finished. It is sectional drawing of the reactor apparatus in the 1st modification of embodiment.

Explanation of symbols

A reactor device B reactor 1 core 2 coil 3 case 4 middle case 10 middle part core 11 gap spacer 12 side part core 15 outer bobbin 21 annular part 22 connection part 23 terminal 30 heat radiation resin layer Ra linear part Rb curved part Rp flat part

Claims (10)

A core having a covering region;
A coil having an annular portion wound around the covering region of the core;
While supporting and storing the core and coil, a case connected to an external heat dissipation member,
From a specific region of the annular portion of the coil, a heat dissipation resin layer formed on a region reaching a portion other than the covering region of the core,
Reactor device equipped with. The reactor device according to claim 1,
The specific area of the annular portion of the coil is a reactor device including a maximum temperature area. The reactor device according to claim 1 or 2,
The core has a track shape composed of two straight portions that become a covering region, and two curved portions connected to the straight portions at both ends of each straight portion,
The annular portion of the coil is two annular portions wound around the two straight portions,
The specific region is a corner portion on the upper center portion of each annular portion of the coil,
A portion other than the covering region is a reactor device that is at least one curved portion of the core. The reactor device according to claim 3,
The part other than the covering region is a reactor device that is a curved part on both sides of the core. In the reactor apparatus in any one of Claims 1-4,
The reactor device, wherein the heat-dissipating resin layer reaches from the portion other than the covering region of the core to the inner surface of the case. In the reactor apparatus in any one of Claims 1-5,
The heat dissipation resin layer is a reactor device made of an epoxy resin containing a metal filler. Assembling a core having a covering region and a coil having an annular portion surrounding the covering region of the core;
Storing the core and the coil in a case (b);
(C) forming a heat-dissipating resin layer by supplying a resin from a specific region of the coil to a region reaching a portion other than the covering region of the core;
Reactor device assembly method including In the method of assembling the reactor device according to claim 7,
The reactor (c) is an assembly method of a reactor device, which is performed so as to supply the resin until reaching the inner surface of the case after the step (b). In the method of assembling the reactor device according to claim 7,
The step (c) is an assembly method of a reactor device, and is performed so as to supply the resin until reaching the middle of the curved portion of the core before the step (b). In the assembly method of the reactor apparatus in any one of Claims 7-9,
In the step (c), a reactor apparatus assembly method using an epoxy resin containing a metal filler as the resin.

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