JP2006179763A - Electronic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To simplify and miniaturize an arrangement of an electronic device having a wiring circuit board mounted to a case and also an electronic component mounted on the case. <P>SOLUTION: The electronic device comprises a case 100 and a wiring circuit board 200 mounted on the case 100. The case 100 is made of a resin. The casing 100 is integrally formed with a path bar 30 by insert molding. Electronic components 10 and 20 are mounted on the case 100. The electronic components 10 and 20 and the wiring circuit board 200 are electrically connected with each other by the bus bar 30. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electronic device in which a wiring board is attached to a case and an electronic component is mounted.

  Conventionally, an electronic device including a case and a wiring board attached to the case is known. Conventionally, the case is generally a metal case made of aluminum or the like, and the wiring board is a printed board or the like.

  Some of these electronic devices have electronic components mounted directly on the wiring board. However, in order to satisfy requirements such as downsizing of the wiring board and improvement of the mounting area of the wiring board, A technique has been proposed in which a gap between the case and the electronic component is mounted in the gap.

  Conventionally, when an electronic component is mounted in the gap between the wiring board and the case, a wiring unit formed by insert-molding a bus bar with resin has been used.

  Such a wiring unit is called a component carrier, and an electronic component is mounted on the wiring unit, and the wiring unit is disposed in a gap between the wiring board and the case.

  In other words, in this case, the electronic component is mounted on the case via a wiring unit called a component carrier.

  However, when the component carrier as described above is used, the electronic device is composed of three large components, that is, a case, a wiring board, and a component carrier, which increases the number of parts and causes an increase in cost.

  In addition, when the above component carrier is used, even a large electronic component can be mounted without any problem. For example, an electronic component that requires heat dissipation such as a power element does not come into contact with a case made of aluminum or the like. Therefore, at present, a gel for heat dissipation is applied and interposed between the component carrier and the case.

  Thereby, the heat from the power element is transmitted to the case made of aluminum or the like via the component carrier and the heat radiating gel, and is radiated to the outside of the case.

  However, in the structure in which such a heat-dissipating gel is interposed between the component carrier and the case, the heat dissipation efficiency is slightly worse because heat is released via the gel, and the heat dissipation performance due to the movement of the gel is also low. There are problems such as decline.

  The present invention has been made in view of the above problems, and an object of the present invention is to simplify and reduce the size of an electronic device in which a wiring board is attached to a case and an electronic component is mounted.

  In order to achieve the above object, the invention according to claim 1 includes a case (100) and a wiring board (200) attached to the case (100), and the case (100) is made of resin. The case (100) is integrally provided with a bus bar (30) by insert molding, and the case (100) is equipped with electronic components (10, 20), and the electronic components (10, 20). There is provided an electronic device characterized in that the wiring board (200) and the wiring board (200) are electrically connected via a bus bar (30).

  As described above, conventionally, an electronic component to be mounted in the gap between the wiring board and the case is mounted on a component carrier that is a separate component from the case.

  On the other hand, in the present invention, the case (100) is configured as a resin case in which the bus bar (30) is integrally provided by insert molding, so that the case and the component carrier, which are conventionally separate, are separated. It can be integrated and configured as one part. Therefore, the number of parts can be reduced and the apparatus can be downsized.

  Therefore, according to the present invention, in the electronic device in which the wiring board (200) is attached to the case (100) and the electronic component (10.20) is mounted, the configuration can be simplified and downsized. . Further, along with the simplification and miniaturization of this configuration, the cost can be reduced.

  Conventionally, as described above, the heat dissipation path of the electronic component reaches the case via the component carrier and the heat dissipation gel, and further improvement in heat dissipation performance has been desired.

  The invention according to claim 2 further improves the invention according to claim 1 with respect to the problem of heat dissipation performance.

  That is, in the invention according to claim 2, in the electronic device according to claim 1, in the case (100), a part of the electronic component (10, 20) where the electronic component (20) requiring heat dissipation is mounted. The metal plate (50) for heat dissipation is provided by insert molding, and the electronic component (20) and the metal plate (50) that require heat dissipation are thermally connected. .

  According to this, heat from the electronic component (20) that needs to be dissipated is dissipated to the outside substantially only through the metal plate (50), so that it is mounted on the case (100) and needs to be dissipated. The heat dissipation effect of the electronic component (20) can be further improved.

  Here, as in the invention described in claim 3, in the electronic device described in claim 2, the electronic component (20) and the metal plate (50) that require heat dissipation are fixed by screwing. It can be characterized by that.

  As in the invention described in claim 4, in the electronic device described in claim 2, the metal plate (50) has a spring portion (51) protruding in a hook shape outside the case (100). The electronic component (20) that is provided integrally and requires heat dissipation is fixed to the metal plate (50) so as to be pressed by the elastic force of the spring portion (51). .

  As in the invention described in claim 5, in the electronic device described in claims 1 to 4, the case (100) and the wiring board (200) are fixed by screwing. Can be characterized.

  In addition, the code | symbol in the bracket | parenthesis of each said means is an example which shows a corresponding relationship with the specific means as described in embodiment mentioned later.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, parts that are the same or equivalent to each other are given the same reference numerals in the drawings for the sake of simplicity.

  FIG. 1 is a diagram illustrating a schematic plan configuration of a case 100 in an electronic device according to an embodiment of the present invention, and FIG. 2 is a schematic diagram illustrating a state in which electronic components 10 and 20 are mounted on the case 100 illustrated in FIG. It is a top view.

  Further, the electronic device of the present embodiment is attached to the case 100 in the state shown in FIG. 2 so that the wiring board 200 is covered from the upper side of the paper in FIG. FIG. 3 is a view showing a state where the wiring board 200 is attached to the case 100 in a cross section taken along the alternate long and short dash line D in FIG.

  4 is a schematic cross-sectional view along the alternate long and short dash line A in FIG. 2, FIG. 5 is a schematic cross-sectional view along the alternate long and short dash line B in FIG. 2, and FIG. 3 is a schematic cross-sectional view along the alternate long and short dash line C. FIG.

  The electronic device according to the present embodiment is roughly configured to include a case 100, a wiring board 200 attached to the case 100, and electronic components 10 and 20 mounted on the case 100. Such an electronic device can be applied to an engine control ECU, for example.

  Case 100 is made of resin. For example, the case 100 is made by molding a resin material such as PPS (polyphenylene sulfide) or PBT (polybutylene terephthalate) using a mold or the like.

  As shown in FIGS. 1, 2, and 3, a wiring board 200 is attached to the case 100. In the case 100, a portion that supports the wiring board 200 and is attached to the wiring board 200. The support part 110 which is is provided. Here, a printed circuit board or the like can be adopted as the wiring board 200, but it may be a ceramic substrate.

  The method for fixing the wiring board 200 and the case 100 is not particularly limited, but in the present embodiment, fixing by screwing is employed.

  The support part 110 of the case 100 is provided with a screw hole 130 into which the screw 120 for performing the screwing is inserted. In the example shown in FIGS. 1 and 2, the six support portions 110 are each provided with a screw hole 130.

  Then, as shown in FIG. 3, the wiring board 200 is supported on the support portion 110 of the case 100, and screwing is performed via the screws 120, thereby the case 100 and the wiring board 200. Is fixed.

  Here, in the semiconductor device of this example, as shown in FIG. 3, the wiring board 200 is fastened together with the cover 120 provided thereon by screws 120. In this example, the wiring board 200 and the cover 300 are fastened together at the support portions 110 positioned at the four corners of the case 100 having a rectangular plate shape, and only the wiring board 200 is used in the remaining two support portions 110. Screwed.

  As a result, the wiring board 200 is covered with the cover 300. The cover 300 may be made of any material such as resin, metal, or ceramic, and is not particularly limited.

  As shown in FIGS. 1 to 6, the bus bar 30 is embedded in the case 100 and integrated with the case 100. The bus bar 30 is provided integrally with the case 100 by using a resin constituting the case 100 and insert molding with the resin.

  The bus bar 30 is made of a conductive material such as a metal material such as stainless steel, copper, or aluminum. In particular, as shown in FIGS. 4 and 6, both end portions 31 of each bus bar 30 are exposed on the surface of the case 100, and an intermediate portion is located inside the case 100.

  In addition, on the outer periphery of the area where the electronic components 10 and 20 are mounted on the surface of the case 100, a frame portion 140 protruding in a wall shape is provided so as to surround the mounting area. If the electronic components 10 and 20 are arranged on the inner periphery of the frame portion 140, the displacement of the electronic components 10 and 20 can be suppressed as much as possible.

  The electronic components 10 and 20 are mounted on the inner periphery of each frame portion 140 of the case 100. In this example, as shown in FIGS. 4 to 6, each electronic component 10 and 20 is an adhesive. 40 is mounted. Accordingly, the electronic components 10 and 20 and the case 100 are bonded and fixed.

  Here, in the electronic device according to the present embodiment, the electronic components 10 and 20 mounted on the case 100 are a mixture of those that do not require heat dissipation and those that require heat dissipation.

  In the example shown in FIG. 2, the three electronic components 10 located near the left side of the case 100 in the figure do not require heat dissipation, and are large elements such as coils and capacitors, for example. In addition, the three electronic components 20 located near the lower side of the case 100 in the figure need to be dissipated and are large elements such as power transistors, for example.

  Here, in the electronic device of the present embodiment, as shown in FIGS. 1, 2, and 6, a portion of the electronic component 10, 20 in the case 100 where the electronic component 20 requiring heat dissipation is mounted is A metal plate 50 for heat dissipation is provided. The metal plate 50 is provided integrally with the case 100 by insert molding.

  The metal plate 50 is made of a metal having excellent heat dissipation, such as copper or aluminum. Specifically, as shown in FIG. 6, both surfaces of the metal plate 50 are exposed from the case 100.

  As shown in FIG. 6, the electronic component 20 that requires heat dissipation, such as the power transistor, is closely mounted on the metal plate 50 exposed from the case 100, and the periphery thereof is bonded to the adhesive. It is hardened with the agent 40. Thereby, the electronic component 20 and the metal plate 50 are thermally connected.

  Each of these electronic components 10 and 20 includes leads 11 and 21 for electrical connection with the outside of the components. As shown in FIGS. 2, 4, and 6, the leads 21 and 31 of the electronic components 10 and 20 are electrically connected to the end 31 of the bus bar 30 exposed from the case 100.

  Here, examples of means for connecting the leads 21 and 31 of the electronic components 10 and 20 and the bus bar 30 include soldering or wire bonding. When electronic components are mounted on the above-described conventional component carrier, resistance welding is adopted as the connection means. However, in this embodiment, since the bus bar 30 is embedded in the resin case 100, resistance welding is performed. Cannot be adopted.

  Therefore, in this embodiment, soldering, wire bonding, or the like is used as a connection means between the leads 21 and 31 of the electronic components 10 and 20 and the bus bar 30. In the illustrated example, the leads 21 and 31 of the electronic components 10 and 20 and the bus bar 30 are connected by soldering. Solder is not shown.

  On the other hand, some bus bars 30 electrically connect the electronic components 10 at both end portions 31 (see FIG. 2). However, the electronic components 10 and 20 and the wiring board 200 are electrically connected. There are many that are doing.

  For example, as shown in FIGS. 4 and 6, by inserting one end 31 of the bus bar 30 into an electrical connection hole (not shown) formed in the wiring board 200, the bus bar 30 and the wiring board 200 are Are electrically connected.

  In this case, as means for connecting the bus bar 30 to the wiring board 200, soldering by a local jet or the like, press-fit using spring elasticity, wire bonding, or the like can be employed.

  Thus, in the present embodiment, the electronic components 10 and 20 mounted on the case 100 and the wiring board 200 attached to the case 100 are electrically connected via the bus bar 30.

  Although not shown, in the electronic device of the present embodiment, a connector member is electrically connected to the wiring board 200, and the electronic device can be electrically exchanged with the outside via the connector member. ing. For example, the connector member is assembled in such a manner that a part of the connector member is inserted into the gap between the case 100 and the wiring board 200 at the end of the case 100.

  In this electronic device, an electric circuit is constituted by the electronic components 10 and 20 and the wiring board 200 on the case 100, and this electronic device can be applied to, for example, an ECU of a vehicle. it can. Further, in the present embodiment, when the electronic device is operated, heat from the electronic component 20 that needs to be radiated is efficiently radiated to the outside through the metal plate 50.

  Such an electronic device, for example, prepares a case 100 in which a bus bar 30 and a metal plate 50 are insert-molded and integrated. The electronic components 10 and 20 are mounted on the case 100 and the bus bar 30 is electrically connected. It can be manufactured by attaching the wiring board 200 to the case 100 and then making electrical connection with the bus bar 30.

  In the example shown in FIG. 3, the wiring board 200 is mounted on the case 100, for example, the wiring board 200 is screwed at the two support portions 110, and the cover 300 is mounted thereon. Try to screw it in.

[Effects]
By the way, according to the present embodiment, the case 100 and the wiring board 200 attached to the case 100 are provided. The case 100 is made of resin, and the bus bar 30 is integrally provided in the case 100 by insert molding. An electronic device characterized in that the electronic components 10 and 20 are mounted on the case 100, and the electronic components 10 and 20 and the wiring board 200 are electrically connected via the bus bar 30. Provided.

  As described above, conventionally, an electronic component to be mounted in the gap between the wiring board and the case is mounted on a component carrier that is a separate component from the case.

  On the other hand, in the present embodiment, the case 100 is configured as a resin case in which the bus bar 30 is integrally provided by insert molding, thereby integrating the case and the component carrier, which have conventionally been separate. It can be configured as one part. Therefore, the number of parts can be reduced and the apparatus can be downsized.

  Therefore, according to the present embodiment, it is possible to simplify the configuration and reduce the size of the electronic device in which the wiring board 200 is attached to the case 100 and the electronic components 10 and 20 are mounted. Further, along with the simplification and miniaturization of this configuration, the cost can be reduced.

  Further, in the electronic device of the present embodiment, in the case 100, a heat radiating metal plate 50 is provided by insert molding at a portion of the electronic components 10, 20 where the electronic component 20 requiring heat dissipation is mounted. Another feature is that the electronic component 20 that requires heat dissipation and the metal plate 50 are thermally connected.

  According to this, heat from the electronic component 20 that needs to be dissipated is dissipated to the outside substantially only through the metal plate 50, so that the heat dissipated from the electronic component 20 that is mounted on the case 100 and needs to be dissipated. The effect can be further improved.

  In other words, conventionally, as described above, the heat dissipation path of the electronic component is to reach the case through the component carrier and the heat dissipation gel, and further improvement in heat dissipation performance has been desired. Since the heat dissipation path of the electronic component in the embodiment is substantially only the metal plate 50, the heat dissipation performance is improved.

  Incidentally, in the past, in order to improve the heat dissipation efficiency of the electronic component, it is conceivable to directly mount the power element on the case. However, the conventional case is made of a metal such as aluminum. In this case, the heat dissipation effect of the power element is enhanced, but the bus bar serving as the wiring cannot be installed. Moreover, when using a resin case, installation of a bus bar is possible, but the heat dissipation effect of a power element cannot be expected so much.

  In the electronic device of the present embodiment, the conflicting problems of the integration of the bus bar and the heat dissipation performance are appropriately solved, and the case 100 realizes a case with excellent heat dissipation while integrating the bus bar. It is.

[Modification]
In the example shown in FIG. 6, the thermal connection between the electronic component 20 that needs to be dissipated and the metal plate 50 is performed by mounting the electronic component 20 in close contact with the exposed metal plate 50 and surrounding the periphery thereof. This was done by hardening with an adhesive 40.

  On the other hand, other examples of thermal connection means between the electronic component 20 and the metal plate 50 include the following examples as shown in FIG. 7 and FIG. FIG. 7 is a schematic cross-sectional view showing a first modified example, and FIGS. 8A and 8B are a schematic cross-sectional view and a schematic plan view of the second modified example. In FIG. 8, (b) is a top view of (a).

  In the first modification shown in FIG. 7, the electronic component 20 that requires heat dissipation and the metal plate 50 are fixed by screwing. As shown in FIG. 7, both the members 20 and 50 are screwed through screws 60 in a state where the electronic component 20 is in close contact with the metal plate 50. Thereby, thermal connection between the electronic component 20 and the metal plate 50 is realized.

  Further, in the second modified example shown in FIG. 8, the metal plate 50 has a spring-like structure, and the electronic component 20 is sandwiched between them. As shown in FIG. 8, the metal plate 50 is integrally provided with a spring portion 51 that protrudes in a hook shape outside the case 100.

  The electronic component 20 that requires heat dissipation is fixed to the metal plate 50 so as to be pressed by the elastic force of the spring portion 51. In this case, the metal plate 50 is preferably made of a material excellent in spring elasticity. Thus, also in this example, thermal connection between the electronic component 20 and the metal plate 50 is realized.

  In the example shown in FIG. 3, the case 100 and the wiring board 200 are fixed by screwing, but the wiring board 200 is fastened together with the cover 300 provided thereon.

  FIG. 9 is a schematic cross-sectional view showing another example of a method for fixing the case 100 and the wiring board 200 in the present embodiment. In the example shown in FIG. 9, the wiring board 200 and the cover 300 thereon are screwed separately. In this case, after the wiring board 200 is screwed to the case 100, the cover 300 may be mounted on the case 100 and screwed to the case 100.

(Other embodiments)
In the above embodiment, the electronic components mounted on the case include those that do not require heat dissipation and those that do not require heat dissipation. There may be no plate.

  Further, as a matter of course, the electronic components mounted on the case are not limited to the coils, capacitors, power transistors and the like shown in the above embodiment.

  Moreover, the fixing method of a case and a wiring board is not limited to the above-mentioned screwing, Other methods, such as adhesion | attachment, may be sufficient.

  In addition, the connection between the electronic component and the metal plate that require heat dissipation is the method described in the above embodiment if the two members are thermally connected and the electronic component is fixed to the case. Other methods may be adopted.

  In addition, the arrangement configuration and shape of the electronic components, bus bars, case support portions, and the like as shown in each of the above drawings show an embodiment applicable to the electronic device of the present invention. It is not limited to the examples shown.

  In short, according to the present invention, in an electronic device including a case and a wiring board attached to the case, the case is made of resin, and the bus bar is integrally provided by insert molding. The main part is that the electronic component and the wiring board are electrically connected via the bus bar. The other parts can be appropriately changed in design.

It is a schematic plan view of the case in the electronic device which concerns on embodiment of this invention. It is a schematic plan view which shows the state which mounted the electronic component in the case shown by FIG. It is a schematic sectional drawing which shows the state by which the wiring board was attached to the case shown by FIG. FIG. 3 is a schematic cross-sectional view along an alternate long and short dash line A in FIG. 2. FIG. 3 is a schematic cross-sectional view taken along one-dot chain line B in FIG. 2. It is a schematic sectional drawing in alignment with the dashed-dotted line C in FIG. It is a schematic sectional drawing which shows the 1st modification of the said embodiment. (A) is a schematic sectional drawing which shows the 2nd modification of the said embodiment, (b) is a top view top view of (a). It is a schematic sectional drawing which shows the other example about the fixing method of the case and wiring board in the said embodiment.

Explanation of symbols

10 ... electronic components, 20 ... electronic components that require heat dissipation, 30 ... bus bars,
50 ... Metal plate, 51 ... Spring part of metal plate, 100 ... Case,
200: A wiring board.

Claims (5)

Case (100),
A wiring board (200) attached to the case (100),
The case (100) is made of resin,
In the case (100), a bus bar (30) is integrally provided by insert molding,
Electronic parts (10, 20) are mounted on the case (100),
The electronic device (10, 20) and the wiring board (200) are electrically connected via the bus bar (30). In the case (100), a heat radiating metal plate (50) is provided by insert molding at a portion of the electronic component (10, 20) where the electronic component (20) requiring heat dissipation is mounted. ,
The electronic device according to claim 1, wherein the electronic component (20) that requires heat dissipation and the metal plate (50) are thermally connected. The electronic device according to claim 2, wherein the electronic component (20) requiring heat dissipation and the metal plate (50) are fixed by screwing. The metal plate (50) is integrally provided with a spring portion (51) protruding in a hook shape outside the case (100),
The electronic component (20) according to claim 2, wherein the electronic component (20) that requires heat dissipation is fixed to the metal plate (50) so as to be pressed by the elastic force of the spring portion (51). apparatus. 5. The electronic device according to claim 1, wherein the case (100) and the wiring board (200) are fixed by screwing.

Images