JP2019216195A - Heat dissipation structure of winding portion - Google Patents

Abstract

To suppress a large variation in the heat radiation performance of a winding portion even when the dimensional tolerance of the winding portion is large.SOLUTION: A heat dissipation structure of a winding portion includes a circuit board 1, a heat dissipating member 2 disposed opposite to a first main surface 1a of the circuit board 1, a winding portion 3 mounted on the first main surface 1a side of the circuit board 1, a heat conducting member 4 interposed between the heat dissipating member 2 and the winding portion 3, and an interval adjusting mechanism 5 that adjusts the interval between the circuit board 1 and the winding portion 3.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a heat radiation structure of a winding part.

  Patent Document 1 discloses a heat dissipation structure that dissipates heat of a heat-generating component to a heat-dissipating member by disposing a heating component such as a switching element or a power module mounted on the circuit board between the circuit board and the heat-dissipating member. Have been. Specifically, in the heat dissipation structure of Patent Document 1, an elastic heat dissipation sheet is interposed between the heat generating component and the heat dissipation member. Furthermore, in the heat dissipation structure of Patent Literature 1, an elastic member is provided between the circuit board and a board supporting portion that supports the circuit board. In the heat dissipation structure of Patent Document 1, the circuit board and the heat-generating component are pressed against the heat-dissipation member by the elastic force of the elastic member, so that the heat-dissipation sheet is elastically compressed and the adhesion between the heat-generation component and the heat-dissipation member is increased. The heat transfer from the heat generating component to the heat radiating member is improved.

JP 2012-200055 A

  By the way, in this kind of heat dissipation structure, there is also a structure in which a heat generating component is a winding portion formed by winding a conductive wire such as a toroidal coil. The dimensions of the winding part (particularly the dimensions in the arrangement direction of the circuit board and the heat radiating member) vary greatly depending on the winding method of the wire. If the dimensional tolerance (variation in dimension) of the winding part is large, even if the gap between the winding part and the heat dissipating member is filled with a heat conductive member such as a heat dissipating sheet, the variation in the interval between the winding part and the heat dissipating member is increased. Becomes large. For this reason, there is a problem that a large variation occurs in the heat radiation performance of the winding part (performance of dissipating the heat of the winding part to the heat radiation member).

  The dimensional tolerance of the winding part is much larger than the dimensional tolerance of the switching element or the power module. For this reason, in the heat dissipation structure as disclosed in Patent Literature 1, there is a limit to the length of the elastic member displacing the positions of the circuit board and the winding portion by the elastic force. That is, it is difficult for the elastic member to absorb the dimensional tolerance of the winding portion and suppress the variation in the interval between the winding portion and the heat radiating member. Further, in a device in which the distance between the circuit board and the heat radiating member cannot be changed, the heat radiating structure as disclosed in Patent Document 1 cannot be adopted.

  The present invention has been made in view of the above-described circumstances, and provides a heat radiation structure of a winding part that can suppress a large variation in heat radiation performance of the winding part even when a dimensional tolerance of the winding part is large. The purpose is to:

  One embodiment of the present invention is a circuit board, a heat radiating member disposed to face the first main surface of the circuit board, a winding portion mounted on the first main surface side, the heat radiating member and the winding A heat dissipating structure for a winding part, comprising: a heat conductive member interposed between the winding part and an interval adjusting mechanism for adjusting an interval between the circuit board and the winding part.

  According to the present invention, the interval between the heat radiating member and the winding portion can be adjusted by the interval adjusting mechanism. For this reason, even if the dimensional tolerance of the winding part in the arrangement direction of the circuit board and the heat radiating member is large, it is possible to suppress the variation in the interval between the heat radiating member and the winding part to be small. Thereby, it is possible to suppress a large variation in the heat radiation performance of the winding part.

It is an outline sectional view showing the radiation structure of the winding part concerning a first embodiment of the present invention. FIG. 2 is a schematic cross-sectional view illustrating a manufacturing process of the heat radiation structure of FIG. 1. FIG. 2 is a schematic cross-sectional view for explaining an effect of the heat radiation structure of FIG. 1. It is an outline sectional view showing the modification of the radiation structure of the winding part concerning a first embodiment of the present invention. It is an outline sectional view showing the radiation structure of the winding part concerning a second embodiment of the present invention. It is an outline sectional view showing the radiation structure of the winding part concerning a third embodiment of the present invention.

[First embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 1, the heat dissipation structure of the winding part according to the present embodiment includes a circuit board 1, a heat dissipation member 2, a winding part 3, a heat conduction member 4, and a gap adjusting mechanism 5. .

  The heat radiating member 2 is arranged to face the first main surface 1a of the circuit board 1. That is, the heat radiating member 2 is arranged at an interval from the first main surface 1 a of the circuit board 1. In the present embodiment, the distance between the circuit board 1 and the heat radiating member 2 is kept constant. The heat dissipating member 2 may be supported on the first main surface 1a of the circuit board 1 by a support rod 6 extending from the circuit board 1 to the heat dissipating member 2 as in the illustrated example, but is not limited thereto. The facing surface 2a of the heat radiating member 2 facing the circuit board 1 may be, for example, curved or have irregularities, but is formed flat in the present embodiment.

The heat radiating member 2 is made of, for example, a material that does not deform or hardly deforms even when an external force acts. The heat dissipating member 2 is made of a material having high thermal conductivity, such as aluminum.
The heat dissipating member 2 in the illustrated example has a plurality of heat dissipating fins 11 protruding from a surface facing the opposite surface 2a, but is not limited thereto. The heat dissipating member 2 may be, for example, a single heat sink or a housing for accommodating the circuit board 1, the winding part 3, and the like.

The winding part 3 is mounted on the first principal surface 1a side of the circuit board 1. Thereby, the winding part 3 is located between the circuit board 1 and the heat radiation member 2.
The winding part 3 is configured by winding a conductive wire. The specific configuration of the winding part 3 may be arbitrary. The winding part 3 of the present embodiment constitutes a toroidal coil. In the present embodiment, the winding portion 3 is arranged such that its axis is oriented in the arrangement direction of the circuit board 1 and the heat radiating member 2 (vertical direction in FIG. 1). Irregularities due to the wire appear on the surface of a portion 21 of the winding portion 3 facing the heat radiating member 2 (hereinafter, referred to as a first facing portion 21 of the winding portion 3).
The terminals 23 of the winding part 3 are electrically connected to a wiring pattern (not shown) of the circuit board 1. The method of joining the terminals 23 of the winding part 3 to the circuit board 1 may be arbitrary. In the present embodiment, the terminals 23 of the winding part 3 are inserted into the circuit board 1 and then joined to the circuit board 1 by soldering. The soldering of the terminals 23 of the winding portion 3 to the circuit board 1 may be performed by, for example, a reflow method in which heat is applied to a solder paste printed on the circuit board 1 or a flow of flowing the circuit board 1 into a solder bath. It may be performed by a system or a DIP system.

The heat conduction member 4 is interposed between the heat radiation member 2 and the winding part 3. The heat conduction member 4 is preferably made of a material having high thermal conductivity. Further, the heat conduction member 4 is preferably made of a material that can secure electrical insulation between the heat radiation member 2 and the winding part 3.
The heat conduction member 4 in the present embodiment is a heat dissipation sheet 40 having elasticity. The thickness of the heat radiation sheet 40 changes, for example, by being compressed in the thickness direction.

The gap adjusting mechanism 5 adjusts the gap between the circuit board 1 and the winding unit 3. The specific configuration of the interval adjusting mechanism 5 may be arbitrary. The interval adjusting mechanism 5 according to the present embodiment includes an adjusting screw 31. The adjusting screw 31 is provided on the circuit board 1 so as to extend from the circuit board 1 toward the winding part 3 and support the winding part 3.
A female screw that meshes with the adjusting screw 31 may be formed on the circuit board 1, for example. In the present embodiment, the adjusting screw 31 meshes with the female screw of the female screw member 32 provided on the circuit board 1. The female screw member 32 may be fixed to the circuit board 1 by soldering or the like. The female screw member 32 may be disposed on the first main surface 1a side of the circuit board 1 as in the illustrated example, or may be disposed on the second main surface 1b side of the circuit board 1, for example.

The adjusting screw 31 rotates with respect to the circuit board 1 in a state in which the adjusting screw 31 meshes with the female screw, so that the adjusting screw 31 moves forward and backward in the thickness direction of the circuit board 1. For this reason, in the interval adjusting mechanism 5 of the present embodiment, by rotating the adjusting screw 31 with respect to the circuit board 1, the position of the distal end 33 in the extension direction of the adjusting screw 31 that supports the winding portion 3 is adjusted. It is displaced in the arrangement direction of the substrate 1 and the heat radiation member 2. Thereby, the distance between the circuit board 1 and the winding part 3 and the distance between the winding part 3 and the heat radiation member 2 can be adjusted.
The adjusting screw 31 of the present embodiment may be disposed only on the first main surface 1a side of the circuit board 1, for example, but in the present embodiment, the adjusting screw 31 is inserted through the circuit board 1 so that the adjusting screw 31 can be easily operated. ing. That is, the end of the adjustment screw 31 located on the opposite side to the tip 33 protrudes from the second main surface 1 b of the circuit board 1.

The number of the adjusting screws 31 may be, for example, one. The number of the adjusting screws 31 in the present embodiment is plural. The plurality of adjustment screws 31 support different portions of the winding part 3. The plurality of adjustment screws 31 may be arranged at intervals in the circumferential direction of the winding unit 3, for example. Although two adjustment screws 31 are shown in FIG. 1, the number of the adjustment screws 31 may be, for example, three or more.
The adjusting screw 31 may be made of, for example, a material having electrical insulation. The adjustment screw 31 of the present embodiment is made of a conductive material such as a metal.

  The heat radiation structure of the winding part according to the present embodiment further includes an insulating plate 7 having electrical insulation. The insulating plate 7 is interposed between the tip 33 of the adjusting screw 31 and the winding 3. The insulating plate 7 covers the entire portion 22 of the winding portion 3 facing the first main surface 1a of the circuit board 1 (hereinafter, referred to as a second facing portion 22 of the winding portion 3). The insulating plate 7 may be made of, for example, polycarbonate (PC), polypropylene (PP), or the like. The insulating plate 7 is made of, for example, a heat-resistant resin material (for example, polybutylene terephthalate (PBT)) that is not deformed or melted by heat when the terminals 23 of the winding part 3 are soldered to the circuit board 1. ).

Next, an example of a method (manufacturing method) of manufacturing the heat dissipation structure of the winding part according to the present embodiment will be described.
When manufacturing the heat radiation structure of the winding part, first, the winding part 3 is arranged on the first main surface 1a of the circuit board 1 (first arrangement step). In the arranging step of the present embodiment, the insulating plate 7 is arranged on the tip 33 of the adjusting screw 31 provided on the circuit board 1, and then the winding part 3 is arranged on the insulating plate 7. In this state, the terminals 23 of the winding part 3 are not joined to the circuit board 1.

Next, the distance between the circuit board 1 and the winding part 3 is adjusted (adjustment step). The adjustment step is performed to adjust the distance between the heat radiating member 2 and the winding portion 3. The adjusting step is performed, for example, after performing a second arrangement step of disposing the heat radiating member 2 on the winding part 3 so that the heat conducting member 4 is interposed between the heat radiating member 2 and the winding part 3. May be.
In the present embodiment, the heat dissipation sheet 40 that is the heat conducting member 4 has elasticity. Therefore, if the above-described adjustment step is performed in a state where the heat radiating sheet 40 is interposed between the heat radiating member 2 and the winding part 3, the heat radiating sheet 40 is compressed, and The interval cannot be adjusted accurately. If the heat radiation sheet 40 is excessively compressed, electrical insulation (insulation distance) between the heat radiation member 2 and the winding part 3 may not be secured.

  Therefore, the adjustment step of the present embodiment is performed before the second arrangement step. Specifically, in the adjustment step, first, the jig 9 is arranged on the first main surface 1a of the circuit board 1 as illustrated in FIG. The jig 9 includes a positioning portion 51 located above the first facing portion 21 of the winding portion 3, and a leg portion 52 extending from the positioning portion 51 to the first main surface 1 a of the circuit board 1 and supporting the positioning portion 51. And. The distance S2 between the first main surface 1a of the circuit board 1 and the positioning portion 51 is set to a distance between the heat radiating member 2 and the winding portion 3 (an amount sufficient to ensure electrical insulation between the heat radiating member 2 and the winding portion 3). In consideration of the distance, the distance is set to be slightly smaller than the distance S1 between the first main surface 1a of the circuit board 1 and the heat radiating member 2 (see FIG. 1). The distance S1 between the circuit board 1 and the heat radiating member 2 is determined in advance by the support bar 6 or the like. When disposing the jig 9 on the circuit board 1, the jig 9 may be detachably fixed to the circuit board 1 by, for example, screwing.

Next, the adjusting screw 31 is rotated so that the first facing portion 21 of the winding portion 3 contacts the positioning portion 51 of the jig 9. Thereby, the distance between the circuit board 1 and the winding part 3 (that is, the distance between the heat radiation member 2 and the winding part 3) can be adjusted with high accuracy. Thus, the adjustment process of the present embodiment is completed.
After the completion of the adjustment step, for example, the jig 9 may be removed from the circuit board 1. In the present embodiment, the jig 9 is attached to the circuit board 1 until after the joining step described later in order to maintain the interval between the circuit board 1 and the winding portion 3.

After the adjustment step, the terminals 23 of the winding part 3 are joined to the circuit board 1 (joining step). In the joining step of the present embodiment, the terminals 23 of the winding part 3 are soldered to the circuit board 1. In the joining step, the adjusting screw 31 is fixed to the circuit board 1 so as not to rotate by bonding or the like. Thereby, it is possible to prevent the distance between the circuit board 1 and the winding part 3 from being changed abruptly.
Finally, the jig 9 is removed from the circuit board 1, and the heat radiating member 2 is arranged on the winding portion 3 so that the heat radiating sheet 40 is interposed between the heat radiating member 2 and the winding portion 3 (second arrangement). Step) completes the manufacture of the heat dissipation structure of the present embodiment. In a state where the heat radiating member 2 is arranged on the winding part 3, the heat radiating sheet 40 is preferably compressed between the heat radiating member 2 and the winding part 3.

  As in the manufacturing method of the present embodiment described above, after the adjusting step and the joining step are sequentially performed using the jig 9, the jig 9 is removed, and the heat radiating member 2 is disposed on the winding part 3. Performing the disposing step is also effective when the heat dissipating member 2 is larger than the circuit board 1, for example, as a housing for housing the circuit board 1 and the winding portion 3. That is, since the jig 9 smaller than the heat dissipating member 2 is attached to the circuit board 1 in the joining step, the joining step (particularly, soldering by the flow method or the DIP method) is not hindered by the heat dissipating member 2. It can be easily implemented.

As described above, according to the heat radiation structure of the winding part according to the present embodiment, the distance between the heat radiation member 2 and the winding part 3 can be adjusted by the distance adjusting mechanism 5. For this reason, even if the dimensional tolerance of the winding part 3 in the arrangement direction of the circuit board 1 and the heat radiating member 2 is large, the variation in the interval between the heat radiating member 2 and the winding part 3 can be reduced. Thereby, it is possible to suppress a large variation in the heat radiation performance of the winding part 3.
In particular, in the present embodiment, the variation in the contact area between the winding portion 3 and the heat dissipation sheet 40 and the pressure (contact pressure) at which the winding portion 3 is pressed against the heat dissipation sheet 40 based on the dimensional tolerance of the winding portion 3. Variation can be reduced. Thereby, a difference in thermal resistance (contact thermal resistance) between the winding portion 3 and the heat radiation member 2 due to a dimensional tolerance of the winding portion 3 can be suppressed. As a result, it is possible to suppress a large variation in the heat radiation performance of the winding part 3.

Further, in the heat radiation structure of the winding part according to the present embodiment, the gap adjusting mechanism 5 is configured by the adjusting screw 31 provided on the circuit board 1. Therefore, the distance between the heat radiating member 2 and the winding part 3 can be easily adjusted only by rotating the adjusting screw 31.
In addition, only by controlling the rotational torque of the adjusting screw 31, the pressing force for pressing the winding portion 3 toward the heat radiating member 2 can be appropriately adjusted. Therefore, it is possible to easily prevent an excessive stress from being applied to the winding part 3 based on the pressing force. That is, protection of the winding part 3 can be achieved.

  Further, in the heat radiation structure of the winding part according to the present embodiment, the plurality of adjusting screws 31 support different parts of the winding part 3. For this reason, as illustrated in FIG. 3, the height positions of the distal ends 33 of the plurality of adjustment screws 31 with respect to the first main surface 1 a of the circuit board 1 are different from each other, so that Can be changed. Thereby, even if the unevenness of the first facing portion 21 of the winding portion 3 facing the heat radiating member 2 is uneven due to the winding method of the winding portion 3 or the like, the entire first facing portion 21 of the winding portion 3 is radiated. It can be close to the member 2. Therefore, even if the unevenness of the first facing portion 21 of the winding portion 3 is uneven, the heat of the winding portion 3 can be efficiently transmitted to the heat radiation member 2. That is, the heat radiation efficiency of the winding part 3 can be improved.

  Further, in the heat radiation structure of the winding part according to the present embodiment, between the tip part 33 of the adjusting screw 31 and the winding part 3, the third part of the winding part 3 facing the first main surface 1 a of the circuit board 1 is arranged. The insulating plate 7 that covers the whole of the two facing portions 22 is provided. For this reason, even if the adjusting screw 31 has conductivity, the insulation between the winding part 3 and the adjusting screw 31 can be achieved by the insulating plate 7. In particular, since the insulating plate 7 covers the entire second opposing portion 22 of the winding part 3, a sufficient insulation distance between the winding part 3 and the adjustment screw 31 can be secured. Thereby, even if the distance between the adjustment screw 31 and the wiring pattern of the circuit board 1 is short, it is possible to prevent an electrical short circuit from occurring between the winding part 3 and the wiring pattern of the circuit board 1.

  In the heat radiation structure of the winding part according to the present embodiment, the heat conduction member 4 interposed between the heat radiation member 2 and the winding part 3 is the heat radiation sheet 40 having elasticity. Therefore, even if the first facing portion 21 of the winding part 3 facing the heat radiating sheet 40 has irregularities, the first facing portion 21 is pressed against the heat radiating sheet 40 and the heat radiating sheet 40 is elastically deformed. Thus, a contact area between the heat radiation sheet 40 and the first facing portion 21 of the winding part 3 can be secured. Thereby, the heat of the winding part 3 can be efficiently transmitted to the heat dissipation sheet 40. That is, the heat radiation efficiency of the winding part 3 can be improved.

  The heat dissipation structure of the first embodiment may further include, for example, a cylindrical wall portion 8 that covers the entire side portion (outer peripheral surface) of the winding portion 3 as shown in FIG. The cylindrical wall portion 8 is formed in a cylindrical shape extending in the direction in which the circuit board 1 and the heat radiating member 2 are arranged. The inner peripheral surface of the cylindrical wall portion 8 is located at an interval with respect to the side portion of the winding portion 3. The cylindrical wall portion 8 may be formed integrally with the insulating plate 7 as illustrated in FIG. 4, or may be formed separately from the insulating plate 7 and fixed to the insulating plate 7, for example. The end of the cylindrical wall portion 8 located on the heat dissipating member 2 side may be in contact with, for example, the opposing surface 2a of the heat dissipating member 2, or may be spaced from the opposing surface 2a as illustrated in FIG. May be located. The axial dimension of the cylindrical wall portion 8 is such that the cylindrical wall portion 8 is pressed against the facing surface 2 a of the heat radiating member 2 even when the distance between the winding portion 3 and the heat radiating member 2 is adjusted by the space adjusting mechanism 5. It is good to be set so that there is nothing.

In the configuration illustrated in FIG. 4, the tubular wall portion 8 suppresses or prevents heat that has escaped into the air from the side of the winding portion 3 from reaching the circuit board 1. That is, the circuit board 1 can be protected from the heat of the winding part 3. Further, the heat that has escaped into the air from the side of the winding part 3 is more easily transmitted to the heat radiation member 2 than to the circuit board 1. That is, the heat of the winding part 3 can be efficiently released to the heat radiation member 2.
The cylindrical wall portion 8 may have, for example, a heat insulating property in which the heat of the winding portion 3 is not easily transmitted from the inside of the cylindrical wall portion 8 to the outside (outer peripheral surface side). Further, the insulating plate 7 may have a heat insulating property like the cylindrical wall portion 8. Further, the cylindrical wall portion 8 may have electrical insulation properties, for example, like the insulating plate 7.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG. In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

As shown in FIG. 5, the heat radiating structure of the winding part of the present embodiment includes a circuit board 1, a heat radiating member 2, a winding part 3, a heat conducting member 4, and a gap adjusting mechanism 5 similar to those of the first embodiment. .
However, the heat dissipation structure of the present embodiment includes an insulating cap 7C having electrical insulation instead of the insulating plate 7 (see FIG. 1) of the first embodiment. The insulating cap 7C covers the tip 33 of the adjusting screw 31. That is, the insulating cap 7 </ b> C is interposed between the winding part 3 and the tip 33 of the adjustment screw 31. In the illustrated example, the surface of the insulating cap 7C that contacts the second facing portion 22 of the winding part 3 is formed in a spherical shape, but may be formed in any shape.

The heat radiation structure of the winding part according to the second embodiment has the same effects as the first embodiment.
In the heat radiation structure of the winding part according to the second embodiment, the tip 33 of the adjusting screw 31 is covered with the insulating cap 7C. For this reason, even if the adjusting screw 31 has conductivity, the insulating cap 7C can achieve electrical insulation between the winding part 3 and the adjusting screw 31. Thereby, even if the distance between the adjustment screw 31 and the wiring pattern of the circuit board 1 is short, it is possible to prevent an electrical short circuit from occurring between the winding part 3 and the wiring pattern of the circuit board 1.
When the insulating cap 7C is employed, the second facing portion 22 of the winding portion 3 facing the first main surface 1a of the circuit board 1 can be opened. For this reason, the heat of the winding part 3 can be released into the air from the second facing part 22 as compared with the case where the entire second facing part 22 of the winding part 3 is covered with the insulating plate 7. Therefore, the heat radiation efficiency of the winding part 3 can be improved.

[Third embodiment]
Next, a third embodiment of the present invention will be described with reference to FIG. In the third embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

As shown in FIG. 6, the heat radiating structure of the winding part of the present embodiment includes a circuit board 1, a heat radiating member 2, a winding part 3, a heat conductive member 4D, and a gap adjusting mechanism 5 as in the first embodiment. Prepare. Further, the heat radiation structure of the winding part of the present embodiment also includes the same insulating plate 7 as in the first embodiment.
However, the heat conducting member 4D in the present embodiment is a sealing resin 40D that seals the first facing portion 21 of the winding portion 3 facing the heat radiating member 2. The sealing resin 40D is preferably a resin such as an epoxy resin that does not deform or hardly deforms even when an external force acts.

The thickness T1 of the sealing resin 40D covering the surface of the first facing portion 21 of the winding part 3 facing the heat radiating member 2 depends on the size of the winding part 3 in the arrangement direction of the circuit board 1 and the heat radiating member 2. It is good to be the same (constant). Thereby, the distance between the heat radiating member 2 and the winding portion 3 in a state where the sealing resin 40D is in contact with the heat radiating member 2 can be kept constant irrespective of the dimensions of the winding portion 3 described above.
The sealing resin 40D may cover the side portion of the winding portion 3 (the end in the left-right direction of the winding portion 3 in FIG. 6) as in the illustrated example, but may not be covered, for example.

The heat radiation structure of the winding part according to the third embodiment has the same effect as the first embodiment.
In the heat dissipation structure of the winding part according to the third embodiment, the heat conduction member 4D interposed between the heat dissipation member 2 and the winding part 3 seals the first facing part 21 of the winding part 3. The sealing resin 40D. The sealing resin 40D is not deformed or hardly deformed by an external force as compared with the heat radiating sheet 40 (see FIG. 1) of the first embodiment, so that the heat radiating member is used without using the jig 9 (see FIG. 2). The position of the winding part 3 with respect to 2 can be easily and accurately adjusted by the interval adjusting mechanism 5. That is, the distance between the winding part 3 and the heat radiating member 2 can be adjusted in a state where the heat radiating member 2 is arranged on the winding part 3. Therefore, it is possible to improve the manufacturing efficiency of the device including the heat radiation structure of the winding portion.

Using the sealing resin 40D as the heat conducting member 4D as in the third embodiment is also applicable to the heat dissipation structure of the second embodiment.
The heat dissipation structure of the third embodiment including the insulating plate 7 may include, for example, the cylindrical wall portion 8 illustrated in FIG.

  Note that even in the heat dissipation structure of the third embodiment, if the heat dissipation member 2 is larger than the circuit board 1 such as a housing for accommodating the circuit board 1 and the winding portion 3, for example, the first embodiment will be described. Similarly to the case of the embodiment, after the adjusting step and the joining step are sequentially performed using a jig 9 smaller than the heat radiating member 2, the jig 9 is removed and the heat radiating member 2 is arranged on the winding part 3. Two arrangement steps may be performed. In this case, the joining step (particularly, soldering by a flow method or a DIP method) can be easily performed without being hindered by the heat radiation member 2.

  Although the details of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  In the present invention, the adjusting screw constituting the interval adjusting mechanism may be made of, for example, a material having electrical insulation. In addition, the adjustment screw may be located at an interval enough to ensure electrical insulation with respect to the wiring pattern of the circuit board, for example. In such a case, an electrical short circuit occurs between the winding portion and the wiring pattern of the circuit board even if no insulating plate or insulating cap is interposed between the winding portion and the adjusting screw. Can be prevented.

  In the present invention, the winding unit is not limited to a toroidal coil, and may be an arbitrary winding component such as a transformer or a choke coil.

DESCRIPTION OF SYMBOLS 1 Circuit board 1a 1st main surface 2 Heat dissipation member 3 Winding part 4, 4D Heat conduction member 5 Interval adjustment mechanism 7 Insulating plate 7C Insulation cap 31 Adjustment screw 33 Tip part 40 Heat dissipation sheet 40D Sealing resin

Claims (7)

A circuit board,
A heat dissipating member opposed to the first main surface of the circuit board,
A winding portion mounted on the first main surface side,
A heat conductive member interposed between the heat radiating member and the winding portion,
A heat radiating structure for a winding part, comprising: a gap adjusting mechanism for adjusting a gap between the circuit board and the winding part. The gap adjusting mechanism includes an adjusting screw provided on the circuit board so as to extend from the circuit board toward the winding section and support the winding section,
The heat dissipation structure of a winding part according to claim 1, wherein the position of the tip of the adjustment screw that supports the winding part in the extension direction is displaced by rotating the adjustment screw with respect to the circuit board.   The heat dissipation structure for a winding part according to claim 2, wherein the plurality of adjustment screws support different parts of the winding part.   3. An insulating plate having electrical insulation property and interposed between a tip portion of the adjusting screw and the winding portion and covering an entire portion of the winding portion facing the first main surface. 4. A heat dissipation structure for a winding part according to claim 3.   The heat dissipation structure of a winding part according to claim 2 or 3, further comprising an insulating cap having electrical insulation properties and covering a tip portion of the adjustment screw.   The heat dissipation structure of the winding part according to any one of claims 1 to 5, wherein the heat conduction member is a heat dissipation sheet having elasticity.   The heat dissipation structure of a winding part according to any one of claims 1 to 5, wherein the heat conduction member is a sealing resin that seals a part of the winding part facing the heat dissipation member.

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