JP4489112B2 - Electronic board mounting structure - Google Patents

Description

  The present invention relates to an electronic board mounting structure for transferring heat generated from a heat generating component mounted on an electronic board to a mounting base to dissipate it.

Various structures have been proposed for the electronic board mounting structure for dissipating the heat generated by the heat generating components mounted on the electronic board to the mounting base.
For example, an electronic component in which a heat generating component is fixed to one of the copper foil patterns on the front and back of a circuit board communicated by a large number of through-hole platings, and the other copper foil pattern is fixed in contact with a heat sink via a heat conductive sheet Is disclosed (see Patent Document 1).
In addition, the electronic substrate is sandwiched between the annular peripheral wall portion of the cover and the heat transfer base portion, and the heat generated by the heat generating component mounted on the electronic substrate is transferred to the base via the heat transfer soft insulating layer. A housing structure of such an in-vehicle electronic device is disclosed (see Patent Document 2).

JP-A-8-204072 (page 2-3, FIG. 2) JP 2004-166413 A (5th page, FIG. 8)

In the conventional electronic component cooling device as disclosed in Patent Document 1, it is necessary to attach and fix the heat conductive sheet to the heat radiating plate corresponding to the electronic component, which leads to an increase in manufacturing cost. was there. Also, if the thickness of the heat conductive sheet is made too thin, there is a risk of dielectric breakdown due to the solder protruding into the through-hole plating part. For this reason, if a sheet with a corresponding thickness is used, the thermal conductivity is lowered. There was a problem of fear.
In the case structure according to Patent Document 2, heat is transferred via a heat-conductive soft insulating layer, but there is no means for regulating the thickness of the soft insulating layer, and the thickness is indeterminate due to manufacturing variations in the dimensions of each part. As a result, there is a problem that the heat transfer characteristics are not stable.

  According to the present invention, in an electronic board that is housed in a housing and on which a heat generating component is mounted, the heat generated by the heat generating component can be reliably and stably transferred to the base member that serves as a heat radiator. It is an object of the present invention to provide an easy electronic board mounting structure.

In the electronic board mounting structure according to the present invention, an electronic board on which a heat- generating component is mounted is housed in a housing composed of a base member made of a heat conductive material and a cover member covering the base member. In the mounting structure of the electronic board in which the outer peripheral part is sandwiched and held by the peripheral wall part of the base member and the cover member, the electronic board is soldered to which the heat-radiating electrode of the heat-generating part is soldered to the mounting surface of the heat-generating part A first heat transfer pattern having a surface is formed, and a second heat transfer pattern connected to the first heat transfer pattern by a plurality of heat transfer through holes is formed on the non-mounting surface, for heat transfer. A heat transfer plating layer is applied to the inner surface of the through hole, and the heat transfer through hole is provided in the region of the first and second heat transfer patterns and outside the solder connection surface. On the part facing the second heat transfer pattern A heat transfer pedestal having a facing surface formed with a separation protrusion contacting the non-mounting surface, and conducting heat to a gap formed between the facing surface and the second heat transfer pattern by the separation protrusion. The adhesive member is filled, and the cover member and the base member are filled with a waterproof sealing material at the joint and are fastened by a coupling screw in a state where the electronic substrate is sandwiched.

According to the mounting structure of the electronic board according to the present invention, in the mounting structure of the electronic board on which the heat generating component is mounted, the electronic board is formed with the first heat transfer pattern in which the heat generating component is solder-connected to the mounting surface. A heat transfer pedestal in which a second heat transfer pattern connected to the first heat transfer pattern by a plurality of heat transfer through holes is formed on the non-mounting surface, and a separation protrusion is formed on the base member A gap formed between the opposing surface of the heat transfer pedestal and the second heat transfer pattern by the separation protrusion, and a heat conductive adhesive is filled into the joint between the cover member and the base member. Since the waterproof seal material is filled and the electronic board is sandwiched and fastened with the coupling screw, the gap between the second heat transfer pattern and the heat transfer pedestal can be secured with a stable dimension. To obtain excellent heat transfer and heat dissipation characteristics. It can be.
Moreover, since the heat conductive adhesive material is used, the heat transfer sheet material and its attaching work are not required, and the workability is improved.
In addition, by providing the heat transfer through hole outside the solder connection surface, the heat transfer connection between the first and second heat transfer patterns can be made with simple means, and the solder flows into the heat transfer through hole. The protrusions
Thus, it is possible to avoid contact conduction with the formed heat transfer pedestal portion or to maintain a minute gap, and a stable gap portion can be secured.

Embodiment 1 FIG.
1 is a plan view showing an electronic board mounting structure according to Embodiment 1 of the present invention. 2 is a cross-sectional view taken along line II-II in FIG. 1, FIG. 3 is an enlarged cross-sectional view of the main part of FIG. 2, and FIG. 4 is a cross-sectional view taken along line IV-IV in FIG.

In FIG. 1, a base member 1 is made of a material having high thermal conductivity, for example, aluminum die-casting, has a bottom surface portion 1a and an annular peripheral wall portion 1b, and has mounting legs 1c on four sides. It can be attached to a wall or the like (not shown) via the attachment foot 1c.
The cover member 2 constituting the housing in combination with the base member 1 is made of a resin molded product, and includes a canopy portion 2a, an annular peripheral wall portion 2b, and a pair of connector housings 2c integrally formed on the peripheral wall portion 2b. Yes. In FIG. 1, the upper half of the canopy 2 a is broken and shown inside.
In the four corners of the base member 1, there are provided through holes 1d into which the coupling screws 3 are inserted, and on the corresponding cover member 2 side, a buried nut (not shown) is embedded. The base member 1 and the cover member 2 are fastened by screwing the four coupling screws 3 inserted into the extraction holes 1d from the back side of the figure into the buried nuts.

The electronic board 5 on which the heat generating component 4 is mounted has a cover surface 2 on which the heat generating component 4 is mounted (hereinafter simply referred to as a mounting surface. The surface opposite to the mounting surface is also referred to as an anti-mounting surface). It is housed on the side. The outer peripheral portion of the electronic substrate 5 is sandwiched and held and fixed by the peripheral wall portions of the base member 1 and the cover member 2.
A plurality of notches 5 a are provided on the outer peripheral portion of the electronic substrate 5. This application will be described later.

The attachment part of the electronic board | substrate 5 is demonstrated based on FIG. 2, FIG. 2 is a cross-sectional view taken along the line II-II in FIG. 1, and FIG. 3 is an enlarged view of a portion III indicated by a one-dot chain line in FIG. However, the cover member 2 is not shown in FIG.
As shown in FIG. 2, the base member 1 shelf-receives the electronic substrate 5 at a step portion provided on the inner peripheral side of the peripheral wall portion 1 b and transfers heat generated from the heat generating component 4 mounted on the electronic substrate 5. The heat transfer pedestal portion 6 is provided corresponding to the mounting position of the heat generating component 4.

As shown in FIG. 3, a heat radiation electrode 9 is provided on the substrate surface side of the heat generating component 4. A first heat transfer pattern 13 is formed on the mounting surface of the electronic substrate 5 on which the heat generating component 4 is mounted, and a second heat transfer pattern 14 is formed on the non-mounting surface. Details of the heat transfer pattern will be described later.
On the other hand, the heat transfer base portion 6 is provided at a portion facing the second heat transfer pattern 1 4, on the facing surfaces of its second heat transfer pattern 1 4, anti-mounting surface of the electronic substrate 5 A plurality of separation protrusions 6a that come into contact with each other are formed. In the case where the base member 1 is made of aluminum die cast, the heat transfer pedestal portion 6 including the separation protrusion 6 a may be manufactured integrally with the base member 1.

The separation protrusion 6a has a height of about 0.3 mm, for example. By providing the separation protrusion 6 a, a minute gap 7 (hereinafter simply referred to as a gap 7) is formed between the opposing surface of the heat transfer pedestal 6 and the second heat transfer pattern 14. The gap 7 is filled with a heat conductive adhesive 8.
With such a configuration, heat generated from the heat generating component 4 is transferred to the heat transfer pedestal portion side through a path described later.

  In addition, the connecting portion between the base member 1 and the cover member 2 is provided with an engaging convex portion at the end of the peripheral wall portion 1b on the base member 1 side, and a convex portion at the end portion of the peripheral wall portion 2b of the cover member 2. The engagement recessed part which fits is provided. And the waterproof sealing material 10 is filled in both fitting parts, and it clamp | tightens and is fixed by the coupling screw 3 demonstrated previously. At this time, the electronic substrate 5 that is received by the peripheral wall 1 b of the base member 1 is sandwiched and fixed by the peripheral wall of the cover member 2.

  Next, the connector housing 2c will be described with reference to a side sectional view of FIG. As shown in the figure, one end of many L-type connection pins 11 is press-fitted into a pair of connector housings 2 c provided on one surface of the peripheral wall 2 b of the cover member 2, and the other end of the L-type connection pins 11. Is soldered to the electronic substrate 5.

Next, details of the substrate surface of the heat generating component 4 and the electronic substrate 5 on which it is mounted will be described.
5 and 6 show a case where the surface mounting component 4 a is used as the heat generating component 4. FIG. 5 is a cross-sectional view of the mounting portion of the surface mount component, and FIG. 6 is a vertical cross-sectional view. FIG. 7A shows a substrate surface configuration diagram on the mounting surface side, and FIG. 7B shows a substrate surface configuration diagram on the non-mounting surface side.

As shown in FIG. 5, the surface mounting component 4 a that is the heat generating component 4 includes a heat radiation electrode 9 a and a surface connection electrode 12, and is mounted on the electronic substrate 5. The non-mounting surface side of the electronic substrate 5 is in contact with the separation protrusion 6a of the heat transfer pedestal 6 provided on the base member 1, and through the gap 7 regulated by the height dimension of the separation protrusion 6a. It faces the facing surface of the heat transfer pedestal 6. As described above, the gap 7 is filled with the heat conductive adhesive 8.
Further, the first heat transfer pattern 13 is formed on the mounting surface on which the surface mounting component 4a of the electronic substrate 5 is mounted, and the second heat transfer pattern 14 is formed on the non-mounting surface.

As shown in FIG. 6, between the first heat transfer pattern 13 and the second heat transfer pattern 14, a plurality of heat transfer through holes 15 (one in the figure) penetrating the resin base material of the electronic substrate 5. Only a metal plating layer 16 is formed on the inner peripheral surface of the heat transfer through hole 15.
The heat transfer through hole 16 is intended for heat transfer between the heat transfer patterns 13 and 14, but is actually electrically connected.

The configuration of the substrate surface including the heat transfer pattern will be described with reference to FIG. 7A shows the mounting surface side, and FIG. 7B shows the non-mounting surface side. In (a), the first heat transfer pattern 13 is generated by a copper foil pattern provided on the electronic substrate 5 on the mounting surface, and most of the first heat transfer pattern 13 includes a solder connection surface 17 in which a solder paste is applied to the copper foil pattern. It has become. The heat radiation electrode 9a of the surface mount component 4a is soldered to the solder connection surface 17.
The plurality of heat transfer through-holes 15 are provided in the first heat transfer pattern 13 and in an area outside the solder connection surface 17 where the solder paste is not applied. In this region, a solder resist film 18 is applied (see FIGS. 5 and 6).
Further, a signal electrode land 19 is provided outside the first heat transfer pattern 13, and a solder paste is also applied to the signal electrode land 19, and the surface connection electrode 12 of the surface mount component 4a is provided here. It is designed to be soldered.

In FIG.7 (b), the 2nd heat transfer pattern 14 is produced | generated by the copper foil pattern which comprises the electronic substrate 5, and the 1st heat transfer pattern in a mounting surface by the above-mentioned several through-hole 15 for heat transfer. 13 and heat transfer connection.
The second heat transfer pattern 14 has a plurality of window holes 20 at positions where the separation protrusions 6a abut against the plurality of separation protrusions 6a of the heat transfer base 6 described above. Is provided. The window hole 20 is a blank window formed by cutting out the copper foil pattern and exposing the resin base material. A solder resist film 18 is applied to the entire surface of the second heat transfer pattern 14 including the window holes 20, and the separation protrusion 6 a comes into contact with the resin base material via the solder resist film 18. (See FIGS. 5 and 6). By doing so, the second heat transfer pattern 14 and the heat transfer pedestal 6 are electrically insulated.

A method of assembling the electronic board mounting structure configured as shown in FIGS. 1 to 7 will be briefly described.
First, an electronic board 5 on which a large number of electronic components and heat generating components 4 (not shown) are mounted is temporarily fixed to the opening end of the cover member 2, and the L-shaped connection pins 11 are soldered. 2a is placed in the jig with the bottom surface, and the sealing recess 10 of the peripheral wall 2b of the cover member 2 is filled with the waterproof sealing material 10, and the heat transfer pedestal portion of the second heat transfer pattern 14 of the electronic substrate 5 is filled. A heat conductive adhesive 8 is applied to a portion facing 6.
Subsequently, the engagement protrusions provided on the peripheral wall portion 1 b of the base member 1 are fitted to the engagement recesses on the cover member 2 side, and the four corners are tightened and fixed by the coupling screws 3.

According to the electronic substrate structure thus configured, the heat generated in the surface mounting component 4a, which is a heat generating component, is generated from the heat dissipation electrode 9a-the first heat transfer pattern 13-the heat transfer through hole 15-the second heat transfer. Heat is transferred to the pattern 14-heat conductive adhesive 8-heat transfer base 6-base member 1 to be dissipated.
By providing the separation protrusion 6a, the gap (separation dimension) between the second heat transfer pattern 14 of the electronic substrate 5 and the opposing surface of the heat transfer pedestal 6 can be kept constant. By appropriately selecting the height of the separation protrusion 6a, it is possible to make the gap smaller than the thickness dimension of the heat conductive sheet that is normally used, and the thickness of the heat conductive adhesive 8 is minimized. It becomes possible to limit.
In the case of the heat generating component 4 that does not generate a large amount of heat per unit area, the same room temperature drying type liquid silicon resin material can be used for the waterproof sealing material 10 and the heat conductive adhesive 8.

Further, since the waterproof sealing material 10 is not for fixing the base member 1 and the cover member 2, it does not require a strong adhesive capability, and is stably waterproofed using a liquid silicone resin material of room temperature drying type. Can be maintained.
Further, the heat-conductive adhesive 8 does not need a strong bonding capability, and a room temperature dry liquid silicon resin material of the same quality as the waterproof seal material 10 can be used. Desirably, it is more effective to use a mixture of insulating fillers with high thermal conductivity.

Incidentally, after the electronic board 5 accommodated in a housing constituted by a base member 1 and the cover member 2, when the need to remove and dismantle the electronic substrate 5 has occurred, the electronic substrate by removing the cover member 2 After exposing 5, the electronic substrate 5 can be easily peeled off and disassembled from the base member 1 by inserting a tool, for example, a blade edge of a driver or the like into the notch 5 a of the electronic substrate 5 and prying it open.

In the above description, consideration has been given to avoid electrical conduction between the heat radiation electrode 9a of the heat generating component 4 (surface mounting component 4a) and the heat transfer base portion 6, but the heat radiation electrode 9a is a heat generating component. In the case where the four ground electrodes may contact the heat transfer pedestal 6, the window holes 20 provided in the second heat transfer pattern 14 and the solder resist film 18 on the surface thereof are unnecessary. The ground electrode is grounded through the metal heat transfer base and the base. In order to promote conduction, it is effective to use a thermally conductive adhesive 8 that is conductive.
However, even when the heat radiation electrode 4 is a ground electrode, the window hole 20 and the solder resist film 18 may be provided if contact with the heat transfer pedestal 6 is not preferable.

As described above, according to the first embodiment, in the electronic board mounting structure in which the heat generating component is mounted between the base member and the cover member, the heat dissipation of the heat generating component is mounted on the mounting surface of the heat generating component on the electronic substrate. A second heat transfer pattern in which a first heat transfer pattern having a solder connection surface to which an electrode is soldered is formed and connected to the first heat transfer pattern by a plurality of heat transfer through holes on the mounting surface. A pattern is formed, and the base member is provided with a heat transfer pedestal portion having a facing surface formed with a separating protrusion formed in contact with the non-mounting surface at a portion facing the second heat transfer pattern. The gap formed between the opposing surface and the second heat transfer pattern by the protrusion is filled with a heat conductive adhesive, and the cover member and the base member are filled with a waterproof sealant at the joint, Tighten with coupling screws while holding the board Therefore, the separation protrusion can secure the second heat transfer pattern, the heat transfer pedestal, and the gap in a stable dimension, and the gap can be made into a slit size, so it has excellent heat transfer and heat dissipation characteristics. Can be easily obtained.
In addition, since the heat conductive adhesive is used, the heat transfer sheet material and the affixing operation thereof are unnecessary, and the workability is improved.

  In addition, a heat transfer plating layer is applied to the inner surface of the heat transfer through hole, and the heat transfer through hole is provided outside the solder connection surface in the region of the first and second heat transfer patterns. Therefore, the heat transfer connection between the first and second heat transfer patterns can be made by simple means, and solder flows into the heat transfer through-hole to generate a protrusion and make contact with the heat transfer pedestal. Therefore, it is possible to avoid that a minute gap cannot be maintained, and to secure a stable gap portion.

  In addition, the second heat transfer pattern is provided with a window hole in which the pattern is excluded at a portion facing the separation protrusion, and the second heat transfer pattern and the separation protrusion are electrically insulated. In addition to the above-described effects, when the heat radiation electrode of the heat generating component is not a ground electrode, or when it is not a ground electrode and it is not desired to be electrically connected to the base member, an insulation treatment can be reliably performed.

  The heat radiation electrode of the heat generating component is a ground electrode, and the heat transfer pedestal portion and the base member are made of a conductive metal material, and the second heat transfer pattern and the separation protrusion are electrically connected. Therefore, stable heat transfer characteristics can be obtained, and the ground electrode and the base member can be electrically connected by a simple means.

  In addition, since the outer peripheral portion of the electronic substrate is provided with a notch portion into which a tool for separating the electronic substrate from the base member can be inserted, a tool such as a screwdriver is required when the electronic substrate needs to be separated from the base member. Can be easily separated by inserting it into the notch.

Furthermore, the waterproof sealing member and the thermally-conductive adhesive material, since the normal temperature drying type liquid silicone resin material, in attaching process of the electronic substrate can be efficiently applied in the same step.

Embodiment 2. FIG.
Hereinafter, an electronic board mounting structure according to Embodiment 2 of the present invention will be described with reference to the drawings. Since the entire configuration is the same as that shown in FIGS. 1 to 4 described in the first embodiment, illustration and description thereof are omitted. FIG. 8 is a transverse sectional view showing details of the heat generating component in the electronic substrate mounting structure of the second embodiment, and FIG. 9 is a longitudinal sectional view thereof. FIG. 10A is a configuration diagram of the substrate surface on the mounting surface side mainly composed of the first heat transfer pattern, and FIG. 10B is a substrate surface on the side opposite to the mounting surface mainly composed of the second heat transfer pattern. The block diagram is shown. 8 to 10, the same parts as those in FIGS. 5 to 7 are denoted by the same reference numerals, and detailed description thereof is omitted.
The difference from the first embodiment is that a lead component 4 b having a lead terminal 22 penetratingly connected to the connection through hole 21 of the electronic substrate 5 is used as the heat generating component 4.

As shown in FIG. 8, a lead component 4 b having a heat radiation electrode 9 b and a lead terminal 22 is mounted on the mounting surface of the electronic substrate 5. The non-mounting surface faces the heat transfer pedestal 6 provided on the base member 1, and a plurality of separation protrusions 6 a provided on the heat transfer pedestal 6 are in contact with each other. A minute gap 7 that is regulated by the height dimension of the separation protrusion 6 a is formed between the counter-mounting surface and the opposing surface of the heat transfer pedestal 6.
A first heat transfer pattern 23 is provided on the substrate surface of the mounting surface of the lead component 4b, and a second heat transfer pattern 24 is provided on the side opposite to the mounting surface. Details of the heat transfer patterns 23 and 24 will be described later. The gap 7 is filled with a heat conductive adhesive 8.

In FIG. 9, a heat transfer through hole 15 that penetrates the resin base material of the electronic substrate 5 is provided between the first and second heat transfer patterns 23, 24. A metal plating layer 16 is formed on the peripheral surface. The heat transfer through hole 15 is intended for heat transfer between the heat transfer patterns 23 and 24, but is actually electrically connected.
Further, a plurality of through holes 21 for connection are provided on the substrate surface, and a plating layer 16 is also formed on the inner peripheral surface. The lead terminal 22 of the lead component 4b is inserted into the connecting through hole 21 and soldered.

Next, the structure of the substrate surface of each heat transfer pattern part will be described.
In FIG. 10 (a), the first heat transfer pattern 23 is generated by a copper foil pattern provided on the mounting surface of the electronic substrate 5, and a solder paste is provided at a position facing the heat radiation electrode 9b of the lead component 4b. Is applied to the solder connection surface 25, to which the heat radiation electrode 9b of the lead component 4b is soldered.
A number of through holes 15 for heat transfer are provided in a region outside the solder connection surface 25 in the first heat transfer pattern 23, and further, this region, that is, on the first heat transfer pattern 23. Thus, a solder resist film 18 is applied to a region other than the solder connection surface 25 (see FIGS. 8 and 9).
Further, the connection through hole 21 for connecting the lead terminal 22 of the lead component 4 b is provided outside the region of the first heat transfer pattern 23. Of course, it is also outside the region of the second heat transfer pattern 24.

FIG. 10B is the side opposite to the mounting surface, and the second heat transfer pattern 24 is generated by the copper foil pattern of the electronic substrate 5, and the first heat transfer pattern 23 is formed by a large number of through holes 15 for heat transfer. Heat transfer connection.
The plurality of window holes 20 correspond to the positions where the separation protrusions 6a abut, and are blank windows formed by cutting the copper foil pattern and exposing the resin base material. A solder resist film 18 is applied to the entire surface of the second heat transfer pattern 24 including the window hole 20, and the separation protrusion 6 a comes into contact with the resin base material via the solder resist film 18 ( (See FIGS. 8 and 9).

In the above description, consideration has been given to avoid electrical conduction between the heat radiation electrode 9b of the lead component 4b and the heat transfer pedestal 6, but as in the first embodiment, the heat radiation electrode 9b. Is the ground electrode of the lead component 4b and may contact the heat transfer pedestal 6, the window hole 20 provided in the second heat transfer pattern 24 is unnecessary, and the solder on this surface The resist film 18 is also unnecessary.
However, even when the heat dissipation electrode 9b is a ground electrode, the window hole 20 and the solder resist film 18 may be provided if contact with the heat transfer pedestal 6 is not preferable.

In Embodiments 1 and 2, the cover member 2 is formed by integrally forming the canopy 2a and the peripheral wall 2b, but the canopy 2a and the peripheral wall 2b are separate members, It is good also as a housing | casing structure which attaches the canopy part 2a to the surrounding wall part 2b, after tightening and fixing the surrounding wall part 2b and the base member 1 of the member 2. FIG.
Furthermore, in the above description, the base member 1 is a molded product by aluminum die casting. However, the base member 1 may be a sheet metal material produced by pressing, and the separation protrusion in this case is punched out from the back surface of the sheet metal with a pin. What is necessary is just to form with the dowels.

  As described above, according to the second embodiment, in the same configuration as in the first embodiment, the heat generating component is a lead component having a plurality of lead terminals, and the first and second heat transfer patterns are provided on the electronic substrate. In addition to the effects of the first embodiment, the lead terminal of the lead component and its solder connection are provided because the connecting through hole is provided outside the region and the lead terminal is inserted into the connecting through hole and soldered. It can prevent that a part contacts a heat-transfer base part, and is conducted.

It is a top view which shows the attachment structure of the electronic substrate by Embodiment 1 of this invention. It is sectional drawing seen from the II-II line of FIG. It is an expanded sectional view of the principal part of FIG. It is sectional drawing seen from the IV-IV line of FIG. It is a cross-sectional view of the attachment part of the heat-emitting component mounted in the electronic substrate by Embodiment 1 of this invention. It is a longitudinal cross-sectional view of the attachment part of the heat-emitting component shown in FIG. It is a block diagram of the board | substrate surface which mounts the heat-emitting component shown in FIG. It is a cross-sectional view of the attachment part of the heat-emitting component mounted in the electronic substrate by Embodiment 2 of this invention. It is a longitudinal cross-sectional view of the attachment part of the heat-emitting component shown in FIG. It is a block diagram of the board | substrate surface which mounts the heat-emitting component shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base member 1a Bottom face part 1b Peripheral wall part 1c Mounting foot 1d Punching hole 2 Cover member 2a Canopy part 2b Peripheral wall part 2c Connector housing 3 Coupling screw 4 Heating component 4a Surface mounting component (heating component)
4b Lead component (heat generating component) 5 Electronic substrate 5a Notch portion 6 Heat transfer pedestal portion 6a Separation protrusion 7 Gap 8 Thermal conductive adhesive 9 Heat radiation electrode 9a Heat radiation electrode (for surface mount component) 9b Heat radiation electrode (for lead component) )
DESCRIPTION OF SYMBOLS 10 Waterproof sealing material 11 L-shaped connection pin 12 Surface connection electrode 13 1st heat transfer pattern 14 2nd heat transfer pattern 15 Heat transfer through-hole 16 Plating layer 17 Solder connection surface 18 Solder resist film 19 Signal electrode land 20 Window hole 21 Connecting through hole 22 Lead terminal 23 First heat transfer pattern 24 Second heat transfer pattern 25 Solder connection surface.

Claims (6)

An electronic board on which a heat- generating component is mounted is housed in a housing composed of a base member made of a heat conductive material and a cover member that covers the base member, and an outer peripheral portion of the electronic board is placed on the base member and the base member. In the mounting structure of the electronic substrate held and held by the peripheral wall portion with the cover member,
The electronic board is provided with a first heat transfer pattern having a solder connection surface to which a heat radiation electrode of the heat generating component is soldered on a mounting surface of the heat generating component, and a plurality of heat transfer through holes on the non-mounting surface. To form a second heat transfer pattern connected to the first heat transfer pattern by heat transfer,
A heat transfer plating layer is applied to the inner surface of the heat transfer through hole, and the heat transfer through hole is formed in the region of the first and second heat transfer patterns and on the solder connection surface. Provided outside,
The base member includes a heat transfer pedestal portion having a facing surface in which a separation protrusion that contacts the anti-mounting surface is formed at a portion facing the second heat transfer pattern.
The gap formed between the facing surface and the second heat transfer pattern by the separation protrusion is filled with a heat conductive adhesive,
The electronic board mounting structure according to claim 1, wherein the cover member and the base member are joined with a waterproof seal material in a joint portion and are fastened by a coupling screw in a state where the electronic board is sandwiched. 2. The electronic board mounting structure according to claim 1 , wherein the second heat transfer pattern is provided with a window hole in which a pattern is excluded at a portion facing the separation protrusion, and the second heat transfer pattern. A mounting structure for an electronic board, wherein the separation protrusion is electrically insulated. 2. The electronic board mounting structure according to claim 1 , wherein the heat radiation electrode of the heat generating component is a ground electrode, the heat transfer base and the base member are made of a conductive metal material, and the second heat transfer pattern. A mounting structure for an electronic board, wherein the separation protrusion is electrically connected. In the mounting structure of the electronic board according to any one of claims 1 to 3, the outer peripheral portion of the electronic substrate, the notch can be inserted a tool for separating the electronic substrate from the base member A mounting structure for an electronic board, wherein a portion is provided. In the mounting structure of the electronic board according to any one of claims 1 to 3, wherein the waterproof seal member and the heat conductive adhesive material, characterized in that it is a normal temperature drying type liquid silicone resin material Electronic board mounting structure. The electronic board mounting structure according to any one of claims 1 to 3 , wherein the heat generating component is a lead component having a plurality of lead terminals, and the electronic substrate includes the first and second components. An electronic board mounting structure, wherein a through hole for connection is provided outside a region of the heat transfer pattern, and the lead terminal is inserted into the through hole for connection and soldered.

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