JP2019169638A - Heating component mounting structure - Google Patents

Abstract

To provide a heating component mounting structure capable of reducing the size of a product including the heating component mounting structure, reducing electrical loss, and further reducing the manufacturing cost of the product.SOLUTION: A heating component mounting structure includes a heat dissipating part 1 having an arrangement surface 11, a heat generating component 2 having a main body 21 disposed on the arrangement surface 11 and a lead 22 protruding from the main body 21, a first circuit board 3 that is disposed at a distance from the arrangement surface 11 so as to cover the main body 21 and to which the lead 22 is connected, and a second circuit board 4 disposed at a distance from the first circuit board 3 so as to cover at least a part of the first circuit board 3 and electrically connected to the first circuit board 3.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a heat generating component mounting structure.

2. Description of the Related Art Conventionally, there is a mounting structure for a heat generating component in which a heat generating component that generates heat when energized is disposed on a heat radiating component and the heat generating component is connected to a circuit board. In such a mounting structure, heat generated in the heat generating component can be released to the heat radiating component.
Patent Document 1 discloses a circuit board (printed wiring board), a plurality of heat generating parts (heat generating electronic parts) connected to the circuit board and flowing a large current on the arrangement surface of the heat radiating parts (heat sink), and a circuit board. There is disclosed a mounting structure of a heat generating component in which an insert mold substrate is connected to the heat generating component via a plug to flow a large current. In this mounting structure, at a position adjacent to the circuit board, the main body part of the heat generating component and the insert mold substrate are arranged on the arrangement surface of the heat dissipation component.

JP 2004-103816 A

However, in the conventional mounting structure, if the number of heat-generating components increases and wiring (substrate wiring) formed on the circuit board increases, the substrate wiring that constitutes the “circuit” together with the heat-generating components tends to be long. As a result, the circuit board also becomes larger. If the substrate wiring becomes long, an electrical loss due to the wiring increases or noise is generated in the wiring, which is not preferable.
Further, when the circuit board becomes large, the area occupied by the circuit board on the heat dissipation component becomes large. Further, when the main body of the heat generating component is arranged adjacent to the circuit board on the heat radiating component as in Patent Document 1, the arrangement area of the heat generating component on the heat radiating component is also required separately. As a result, there is a problem in that downsizing of the product including the mounting structure is hindered.
In order to make the circuit board small, for example, it is conceivable to increase the number of layers of the circuit board, that is, to form the circuit board with a multilayer wiring board. However, in this case, the manufacturing cost including the mounting structure is increased.

  The present invention has been made in view of the above-described circumstances, and it is possible to reduce the size of a product, reduce electrical loss, and further reduce the manufacturing cost of the product. An object is to provide a mounting structure.

  One aspect of the present invention is directed to a heat dissipating part having an arrangement surface, a heat generating component having a main body part disposed on the arrangement surface and a lead protruding from the main body part, and the arrangement surface so as to cover the main body part. A first circuit board to which the leads are connected, and a first circuit board that covers at least a part of the first circuit board and is spaced from the first circuit board. And a second circuit board electrically connected to the one circuit board.

  According to the present invention, it is possible to reduce the size of a product including a heat generating component mounting structure and to suppress electrical loss to a low level. In addition, the manufacturing cost of the product can be kept low.

It is a schematic plan view which shows the mounting structure of the heat-emitting component which concerns on one Embodiment of this invention. It is II-II arrow sectional drawing of FIG. It is a circuit diagram in the mounting structure of the heat-emitting component of FIGS.

Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
As shown in FIGS. 1 and 2, the heat generating component mounting structure according to the present embodiment includes a heat radiating portion 1, a heat generating component 2, a first circuit board 3, and a second circuit board 4.

  The heat dissipating unit 1 has an arrangement surface 11. The arrangement surface 11 may be formed as a curved surface, for example, but is formed as a flat surface in the present embodiment. Moreover, the thermal radiation part 1 of this embodiment is formed in plate shape. Although the heat radiation part 1 may be comprised with arbitrary materials, in this embodiment, it is comprised with material (for example, copper, aluminum, etc.) with high heat conductivity. The heat radiating unit 1 may constitute a housing (case) that houses the heat-generating component 2, the first circuit board 3, the second circuit board 4, and the like, for example.

  The heat generating component 2 is a component that generates heat when energized. The heat generating component 2 includes a main body portion 21 and leads 22 protruding from the main body portion 21.

The main body 21 is a part that mainly generates heat when energized, and is a mass having a predetermined volume. The main body 21 may be formed in an arbitrary shape, but in the present embodiment, it is formed in a plate shape having a rectangular shape in plan view. Inside the main body 21, a semiconductor element (not shown) which is a main heat source is provided. The electrode of the semiconductor element is connected to the lead 22.
The main body 21 is arranged on the arrangement surface 11 of the heat radiating unit 1. Thereby, the heat generated in the heat generating component 2 can be efficiently released to the heat radiating unit 1.

  The main body 21 may be in direct contact with the arrangement surface 11 of the heat radiating unit 1 as in the illustrated example, but may be arranged on the arrangement surface 11 of the heat radiating unit 1 via, for example, a heat radiating sheet (not shown). In this case, the heat dissipation sheet may be made of a material having high thermal conductivity. Further, the heat dissipation sheet may be made of a material having electrical insulation. In this case, for example, even if a portion having conductivity is exposed on the surface of the main body portion 21 facing the arrangement surface 11 of the heat radiating portion 1, electrical insulation between the main body portion 21 of the heat generating component 2 and the heat radiating portion 1 is performed. Can be secured.

  The main body portion 21 is fixed to the arrangement surface 11 of the heat radiating portion 1. The specific configuration of the fixing means for fixing the main body portion 21 to the heat radiating portion 1 may be arbitrary. The fixing means of this embodiment includes a leaf spring 5 and an attachment portion 6. The leaf spring 5 is formed to be elastically bent and deformable. The leaf spring 5 sandwiches the main body portion 21 between the heat radiating portion 1. The attaching portion 6 attaches the end of the leaf spring 5 to the heat radiating portion 1.

  Specifically, the leaf spring 5 includes a first end portion 31 that sandwiches the main body portion 21 between the heat radiating portion 1 and a second end portion 32 (end portion) that is fixed to the arrangement surface 11 of the heat radiating portion 1 by the attachment portion 6. Part) are integrally formed. The second end 32 of the leaf spring 5 is fixed to the heat dissipation portion 1 by the attachment portion 6 in a state where the first end portion 31 of the leaf spring 5 is overlapped with the main body portion 21 disposed on the arrangement surface 11 of the heat dissipation portion 1. As a result, the leaf spring 5 is elastically bent. The leaf spring 5 presses the main body portion 21 against the arrangement surface 11 of the heat radiating portion 1 by the elastic restoring force of the leaf spring 5 generated at this time. Thereby, the main body portion 21 is fixed to the arrangement surface 11 of the heat radiating portion 1. In the illustrated example, the leaf spring 5 is formed in a strip shape, and the first end portion 31 and the second end portion 32 are arranged in the longitudinal direction of the leaf spring 5, but this is not restrictive.

  The attachment portion 6 only needs to fix the second end portion 32 of the leaf spring 5 to the heat dissipation portion 1. The attachment portion 6 may be, for example, solder or an adhesive that joins the second end portion 32 of the leaf spring 5 to the arrangement surface 11 of the heat radiating portion 1. The attachment portion 6 of the present embodiment is a screw that engages with a screw hole formed in the arrangement surface 11 of the heat radiating portion 1 after being inserted through the second end portion 32 of the leaf spring 5.

  The lead 22 of the heat generating component 2 protrudes from the main body 21 in a direction along the arrangement surface 11 of the heat radiating unit 1 in a state where the main body 21 is arranged on the arrangement surface 11 of the heat radiating unit 1. The leads 22 are located at intervals so as to be electrically insulated from the arrangement surface 11 of the heat radiating unit 1. The lead 22 is bent at a midway portion in the longitudinal direction. Thereby, the front-end | tip part of the protrusion direction of the lead | read | reed 22 is extended in the direction away from the arrangement | positioning surface 11 of the thermal radiation part 1. FIG. The leading end of the lead 22 is connected to the first circuit board 3 described later.

  The heat generating component 2 of this embodiment includes a plurality of (three in the illustrated example) leads 22. The plurality of leads 22 protrude from the main body portion 21 in the same direction. The plurality of leads 22 are spaced from each other in a direction perpendicular to the protruding direction of the leads 22 along the arrangement surface 11 of the heat radiating portion 1 in a state where the main body portion 21 is arranged on the arrangement surface 11 of the heat radiating portion 1. Are arranged.

  For example, only one heat generating component 2 described above may be disposed on the arrangement surface 11 of the heat radiating unit 1, but in the present embodiment, a plurality (four in the illustrated example) of heat generating components 2 are disposed.

  The first circuit board 3 is arranged at an interval with respect to the arrangement surface 11 of the heat dissipating part 1 so as to cover the main body part 21 of the heat generating component 2. The facing surface 41 of the first circuit board 3 that faces the arrangement surface 11 of the heat radiating unit 1 also faces the main body 21 of the heat generating component 2. On the other hand, the first circuit board 3 does not cover the second end portion 32 and the attachment portion 6 of the leaf spring 5. That is, the second end portion 32 and the attachment portion 6 of the leaf spring 5 are located outside the edge of the first circuit board 3 in a plan view as viewed from the arrangement surface 11 side of the heat radiating portion 1.

  The lead 22 of the heat generating component 2 is connected to the first circuit board 3. Specifically, the lead 22 (particularly the tip) of the heat generating component 2 is connected by the first circuit board 3 by solder or the like in a state of penetrating the first circuit board 3 from the facing surface 41 side. The wiring of the first circuit board 3 constitutes a product circuit together with the heat generating component 2.

  The first circuit board 3 is provided with an electronic component 42 (first electronic component 42) that constitutes a product circuit together with the heat generating component 2 and the first circuit substrate 3. The first electronic component 42 may be mounted on the facing surface 41 of the first circuit board 3, for example. In the present embodiment, the first electronic component 42 is mounted on the opposite surface 43 of the first circuit board 3 facing the opposite surface 41 (the same direction as the arrangement surface 11 of the heat radiating portion 1; the Z-axis positive direction). .

The second circuit board 4 is disposed at a distance from the first circuit board 3 so as to cover at least a part of the first circuit board 3. Specifically, the first circuit board 3 and the second circuit board 4 are arranged at intervals in the thickness direction (Z-axis direction). Further, at least a part of the first circuit board 3 is disposed between the second circuit board 4 and the arrangement surface 11 of the heat radiating unit 1. For example, the second circuit board 4 may be arranged so as to cover the entire first circuit board 3, but in the present embodiment, the second circuit board 4 is arranged so as to cover a part of the first circuit board 3.
The second circuit board 4 may or may not cover the second end 32 and the attachment part 6 of the leaf spring 5 that is not covered by the first circuit board 3. In the present embodiment, the second circuit board 4 includes the second end portions 32 of the plate springs 5 of the second end portions 32 and the attachment portions 6 of the plurality of plate springs 5 (two in the illustrated example). The mounting portion 6 is covered, and the second end portion 32 and the mounting portion 6 of the remaining leaf spring 5 are not covered.

The second circuit board 4 is electrically connected to the first circuit board 3. Thus, the wiring of the second circuit board 4 constitutes a product circuit together with the wiring of the first circuit board 3, the heat generating component 2 connected to the first circuit substrate 3, and the first electronic component 42.
The first circuit board 3 and the second circuit board 4 are electrically connected by a connector 7 provided therebetween. The connector 7 is provided on the first circuit board 3 and the second circuit board 4 and is configured to be detachable from each other. The connector 7 is provided on the opposite surface 43 of the first circuit board 3 and the facing surface 51 of the second circuit board 4 facing the first circuit board 3.

  The second circuit board 4 is provided with an electronic component 52 (second electronic component 52) that constitutes a circuit of the product together with the heat generating component 2, the first circuit substrate 3, and the first electronic component 42. The second electronic component 52 may be mounted on the facing surface 51 of the second circuit board 4, for example. In the present embodiment, the second electronic component 52 is mounted on the opposite surface 53 of the second circuit board 4 facing the opposite surface 51 (in the same direction as the arrangement surface 11 of the heat dissipating part 1).

Hereinafter, the mounting structure of the heat generating component 2 of the present embodiment will be described more specifically.
As shown in FIGS. 1 to 3, the heat generating component 2 of the present embodiment is a switching device. That is, the semiconductor element provided in the main body 21 is a switching element such as a MOS transistor. The lead 22 of the heat generating component 2 includes a source lead, a drain lead, and a gate lead connected to the source electrode, drain electrode, and gate electrode of the switching element, respectively.

  The first electronic component 42 provided on the first circuit board 3 includes a drive circuit portion 42 </ b> A that drives the heat generating component 2. The drive circuit portion 42 </ b> A is connected to the gate lead (lead 22) of the heat generating component 2 through the wiring of the first circuit board 3. The drive circuit unit 42A is connected to each of the plurality of heat generating components 2 one by one. That is, the number of drive circuit units 42A in the present embodiment is the same as the number of heat generating components 2.

  Each drive circuit unit 42A is arranged so as to cover each heat generating component 2. Specifically, each drive circuit portion 42 </ b> A is disposed in a region of the first circuit board 3 that overlaps the main body portion 21 of each heat generating component 2 in a plan view as viewed from the arrangement surface 11 side of the heat radiating portion 1. As described above, the heat generating component 2 and the drive circuit unit 42A arranged so as to overlap each other are electrically connected. By arranging the drive circuit portion 42A in this way, the wiring (drive wiring 44) of the first circuit board 3 that connects the heat generating component 2 and the drive circuit portion 42A can be shortened.

Further, in the mounting structure of the present embodiment, the bridge circuit 9 is configured by the plurality of heat generating components 2.
The plurality of heat generating components 2 constituting the bridge circuit 9 may be arranged in a line in one direction along the arrangement surface 11, for example. In the present embodiment, the plurality of heat generating components 2 constituting the bridge circuit 9 constitutes two heat generating component groups 25 arranged side by side in the first direction (Y-axis direction) along the arrangement surface 11 of the heat radiating portion 1. . The two heat generating component groups 25 are arranged along the arrangement surface 11 in the second direction (X-axis direction) orthogonal to the first direction. The two heat generating component groups 25 are located at both ends of the first circuit board 3 in the second direction. In the present embodiment, the number of the heat generating components 2 configuring the bridge circuit 9 is four, and the number of the heat generating components 2 configuring the same heat generating component group 25 is two. That is, in the present embodiment, the four heat generating components 2 are arranged vertically and horizontally in plan view.

The first electronic component 42 also includes a noise removing capacitor 42 </ b> B that removes noise generated in association with driving of the heat generating component 2. In the present embodiment, the noise removing capacitor 42B removes noise generated when the heat generating component 2 that is a switching device is turned on and off, for example. The noise removing capacitor 42B is located between the two heat generating component groups 25 in the second direction. Thereby, the wiring of the 1st circuit board 3 which connects the capacitor 42B for noise removal and each heat-emitting component 2 can be shortened.
The second electronic component 52 provided on the second circuit board 4 is a current detection capacitor for detecting a current flowing through the bridge circuit 9.

  The connector 7 of the present embodiment includes a power connector 7A and a signal connector 7B. The power connector 7 </ b> A is provided to supply a power source current to each heat generating component 2 provided on the first circuit board 3 from the second circuit board 4 side. The power connector 7A is positioned between the two heat generating component groups 25 in the second direction. Thereby, the wiring of the 1st circuit board 3 from the power connector 7A to each heat-emitting component 2 can be shortened. The signal connector 7B is provided to supply a signal current from the second circuit board 4 side to each drive circuit portion 42A provided on the first circuit board 3.

An output terminal 8 is connected to the bridge circuit 9. A load device (not shown) that consumes AC power, such as an AC motor, is connected to the output terminal 8. That is, the mounting structure of the present embodiment can be applied to products such as a power supply device that drives and controls an AC motor or the like.
The output terminal 8 is provided on the first circuit board 3 and is positioned between the two heat generating component groups 25 in the second direction. Thereby, the wiring of the 1st circuit board 3 from each heat-emitting component 2 to the output terminal 8 can be shortened. The output terminal 8 may be provided on the facing surface 41 of the first circuit board 3, for example. In the present embodiment, the output terminal 8 is provided in a region of the opposite surface 43 of the first circuit board 3 that is not covered by the second circuit board 4. Thereby, various load devices can be easily connected to the output terminal 8.

Next, an example of an assembly procedure of the mounting structure of the above-described embodiment will be described.
When assembling the mounting structure of the heat generating component 2, first, the heat generating component 2 is connected to the first circuit board 3. Specifically, after leading the leading end portions of the leads 22 of the plurality of heat generating components 2 through the first circuit board 3, the leading end portions of the leads 22 of the plurality of heating components 2 are attached to the first circuit substrate 3 by soldering or the like. Join. Since the leads 22 of the plurality of heat generating components 2 penetrate the first circuit board 3 in the same direction, the leads 22 of the plurality of heat generating components 2 are bundled on the first circuit board 3 by a single solder flow process. Can be joined together. The positioning of the heat generating component 2 with respect to the first circuit board 3 (for example, the distance between the main body portion 21 of the heat generating component 2 and the first circuit board 3) may be performed using a jig.
The first electronic component 42, the connector 7, and the output terminal 8 may be attached to the first circuit board 3 before and after the heating component 2 is connected to the first circuit board 3.

  Next, the heat generating component 2 and the first circuit board 3 are arranged on the arrangement surface 11 of the heat radiating unit 1. At this time, the main body portion 21 of the heat generating component 2 is arranged on the arrangement surface 11 so that the first circuit board 3 is positioned with a space from the arrangement surface 11 of the heat radiating portion 1. When the heat generating component 2 and the first circuit board 3 are arranged on the arrangement surface 11 of the heat radiating unit 1, for example, the first circuit board 3 may be positioned with respect to the heat radiating unit 1. The positioning of the first circuit board 3 with respect to the heat radiating part 1 is performed, for example, by fixing the first circuit board 3 to the heat radiating part 1 with screws or the like, or a protrusion (not shown) of the heat radiating part 1 protruding from the arrangement surface 11 May be inserted into the first circuit board 3.

  Thereafter, the main body portion 21 of the heat generating component 2 is fixed to the heat radiating portion 1 by the leaf spring 5 and the attachment portion 6 (fixing means). At this time, since the second end portion 32 of the leaf spring 5 is not covered by the first circuit board 3, the second end portion 32 of the leaf spring 5 can be easily fixed to the heat radiating portion 1 by the attachment portion 6. . As a result, the main body portion 21 of the heat generating component 2 is pressed against the arrangement surface 11 of the heat radiating portion 1 by the elastic restoring force of the leaf spring 5 and fixed to the heat radiating portion 1.

Finally, the second circuit board 4 is arranged so that the second circuit board 4 covers a part of the first circuit board 3, and the second circuit board 4 is connected to the first circuit board 3 by the connector 7. The second circuit board 4 may or may not cover the second end 32 and the attachment part 6 of the leaf spring 5 that is not covered by the first circuit board 3. The second electronic component 52 and the connector 7 may be attached to the second circuit board 4 before the second circuit board 4 is connected to the first circuit board 3.
Thus, the assembly of the mounting structure for the heat generating component 2 is completed.

As described above, in the mounting structure of the present embodiment, the main body portion 21 of the heat generating component 2 is arranged on the arrangement surface 11 of the heat radiating portion 1. For this reason, the heat of the heat generating component 2 can be efficiently released to the heat radiating unit 1.
Furthermore, the mounting structure of this embodiment includes two circuit boards 3 and 4 connected to each other. For this reason, even if the number of circuit board wirings (substrate wirings) constituting the product circuit together with the heat generating component 2 is large, the length of the board wiring is shortened by providing the circuit board wiring separately on the two circuit boards. be able to. As a result, electrical loss due to wiring can be suppressed, and generation of noise in the wiring can be suppressed.

Further, by providing the substrate wiring separately on the two circuit boards 3 and 4, the individual circuit boards 3 and 4 can be formed small. Thereby, the occupation area of the circuit boards 3 and 4 in the arrangement | positioning surface 11 of the thermal radiation part 1 can be restrained small. Further, by arranging the first circuit board 3 so as to cover the main body part 21 of the heat generating component 2, the arrangement area of the heat generating component 2 on the arrangement surface 11 of the heat radiating part 1 is ensured separately from the circuit boards 3 and 4. There is no need. As a result, the product can be reduced in size.
Further, by providing the substrate wiring separately on the two circuit boards 3 and 4, the manufacturing cost of the product can be suppressed as compared with the case where the substrate wiring is constituted by one multilayer wiring board.

In the mounting structure of this embodiment, the fixing means for fixing the main body portion 21 of the heat generating component 2 to the heat radiating portion 1 is constituted by the leaf spring 5 and the attachment portion 6. Further, the second end portion 32 and the attachment portion 6 of the leaf spring 5 are arranged at a position that is not covered by the first circuit board 3. For this reason, the area | region which covers the main-body part 21 among the 1st circuit boards 3 can be utilized effectively as an area | region which mounts the components (1st electronic component 42) which comprise a circuit with the heat-emitting component 2. FIG.
Specifically, for example, when the main body 21 of the heat generating component 2 is directly screwed and fixed to the heat radiating section 1, a screw is passed through a region of the first circuit board 3 that covers the main body 21. It is necessary to form a through hole for this purpose. For this reason, the 1st electronic component 42 cannot be mounted in the area | region which covers the main-body part 21 among the 1st circuit boards 3. FIG.
On the other hand, in the mounting structure of the present embodiment, the first electronic component 42 can be mounted on the first circuit board 3 in the area covering the main body 21. Need not be secured separately. Thereby, the first circuit board 3 can be formed small, and the product including the mounting structure can be downsized.

  In the mounting structure of the present embodiment, the main body 21 is fixed to the heat radiating portion 1 by pressing the main body 21 against the heat radiating portion 1 by the elastic restoring force of the leaf spring 5. For this reason, when assembling the mounting structure or when a temperature change occurs during the operation of the product including the mounting structure, the leaf spring 5 is elastically bent, so that the lead 22 and the first circuit board 3 It is possible to relieve stress applied to the connecting portion. Therefore, it is possible to suppress the occurrence of a defect in the connection between the heat generating component 2 and the first circuit board 3.

  Further, in the mounting structure of the present embodiment, the first circuit board 3 is provided with a drive circuit portion 42A that drives the heat generating component 2 that is a switching device. For this reason, the drive circuit portion 42A can be arranged near the heat generating component 2. In particular, in the mounting structure of the present embodiment, the drive circuit unit 42A is disposed so as to cover the heat generating component 2, and therefore the drive circuit unit 42A can be reliably arranged near the heat generating component 2. Thereby, the wiring (drive wiring 44) of the first circuit board 3 from the drive circuit portion 42A to the lead 22 of the heat generating component 2 can be shortened. Therefore, it is possible to suppress the generation of noise (for example, ringing noise) in the drive wiring 44 and to effectively reduce the influence of this noise on the operation of the heat generating component 2.

In the mounting structure of the present embodiment, the plurality of heat generating components 2 constituting the bridge circuit 9 are arranged in the first direction and the second direction orthogonal to each other along the arrangement surface 11. For this reason, compared with the case where all the heat generating components 2 constituting the bridge circuit 9 are arranged in a line in one direction (for example, the first direction), the wiring of the first circuit board 3 constituting the bridge circuit 9 is formed short. It is possible to suppress electrical loss due to wiring.
Further, the length of the wiring of the first circuit board 3 from each heat generating component 2 to the power connector 7A and the output terminal 8 can be made equal among the plurality of heat generating components 2. Thereby, the magnitude | sizes of the power supply current which flows into each heat-emitting component 2 can be made equal among the some heat-emitting components 2, without changing the thickness of the wiring of the 1st circuit board 3. FIG. Therefore, the bridge circuit 9 can be stably operated.

  In the mounting structure of the present embodiment, the first circuit board 3 is provided with a noise removing capacitor 42 </ b> B that removes noise generated in association with driving of the heat generating component 2. For this reason, it is possible to shorten the wiring of the first circuit board 3 from the heat generating component 2 to the noise removing capacitor 42B by arranging the noise removing capacitor 42B near the heat generating component 2. Thereby, the noise can be effectively removed.

  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.

DESCRIPTION OF SYMBOLS 1 Heat radiation part 2 Heat generating component 3 1st circuit board 4 2nd circuit board 5 Leaf spring 6 Mounting part 7 Connector 8 Output terminal 9 Bridge circuit 11 Arrangement surface 21 Main-body part 22 Lead 25 Heat generating component group 32 Second end of leaf spring 5 Part (end)
42 1st electronic component 42A Drive circuit part 42B Noise removal capacitor 52 2nd electronic component

Claims (7)

A heat dissipating part having an arrangement surface;
A heat generating component having a main body portion disposed on the arrangement surface and a lead protruding from the main body portion;
A first circuit board that is arranged at an interval with respect to the arrangement surface so as to cover the main body, and to which the leads are connected;
A second circuit board that is disposed at a distance from the first circuit board so as to cover at least a part of the first circuit board, and is electrically connected to the first circuit board;
A mounting structure for heat-generating components. A leaf spring that is elastically bent and deformable, sandwiches the main body between the heat dissipation portion, and an attachment portion that attaches an end portion of the leaf spring to the heat dissipation portion;
2. The heating component mounting structure according to claim 1, wherein an end portion of the leaf spring and the attachment portion are positioned outside an edge of the first circuit board in a plan view as viewed from the arrangement surface side. The heat generating component is a switching device;
The heat generating component mounting structure according to claim 1, wherein a drive circuit unit for driving the heat generating component is provided on the first circuit board.   The heat generating component mounting structure according to claim 3, wherein the drive circuit unit is disposed so as to cover the heat generating component.   The heat generating component mounting structure according to claim 3 or 4, wherein the drive circuit unit is disposed in a region of the first circuit board that overlaps the main body unit in a plan view as viewed from the arrangement surface side. A bridge circuit is configured by a plurality of the heat generating components,
The two heat generating component groups in which a plurality of the heat generating components are arranged side by side in the first direction along the arrangement surface are arranged in a second direction orthogonal to the first direction along the arrangement surface. The mounting structure of the heat generating component according to any one of items 5.   The heat generating component mounting structure according to any one of claims 1 to 6, wherein the first circuit board is provided with a noise removing capacitor for removing noise generated in association with driving of the heat generating component. .

Images