JP2002271064A - Storage case for electronic parts - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a storage case 1 of electronic parts which can effectively suppress the rise of a temperature in a heating element 5 with inexpensive and simple structure. SOLUTION: The heating element 5 is mounted on a printed board 4, and the extending part 3a of a lower case body 3 is brought into contact with the vicinity of the back face of the printed board 4 which corresponds to the mounting position of the heating element 5. The end of the printed board 4 depresses the extending part 3a downward when the bodies 2, 3 and 4 are assembled by adjusting the printed board 4 and the lower case body 3 so that the extending part 3a has a spring effect generating contact pressure with the printed board 4. Thus, the extending part 3a generates contact pressure with the printed board 4, improves adhesion between the printed board 4 and the extending part 3a, stably transmits heat from the heating element 5 from the extending part 3a to the lower case body 3 and an upper case body 2 through the printed board 4, radiates heat from the whole face of the case body 1, and can suppress the rise of the temperature in the heating element 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a case for housing electronic components used for housing electronic control circuit components such as a vehicle.

[0002]

2. Description of the Related Art Conventionally, for example, an electronic control unit mounted on a vehicle or the like mounts a heating element such as a transistor on a printed circuit board serving as a circuit board, and accommodates the printed circuit board in a case body. When the temperature of the heating element such as a transistor housed in the case body rises above a predetermined temperature, the heating element itself may be destroyed (thermal destruction phenomenon). Therefore, for example, Japanese Patent Application Laid-Open No. 6-50704
Japanese Patent Application Laid-Open No. 9-29409 discloses a technique for suppressing the temperature rise of the heating element. According to Japanese Patent Publication No. Hei 6-507049, a cover made of a heat conductive material is provided on the surface of a printed circuit board, and the cover is brought into contact with the case. Thus, heat conduction to the heating element, the cover, and the case body suppresses a temperature rise of the heating element.

[0003]

Problems to be solved by the Invention
The case body of the electronic control device disclosed in Japanese Patent Application Publication No. 07049 has a special configuration of a cover made of a heat conductive material on the surface of a printed circuit board in order to suppress a rise in temperature of the heating element. Since the formation process is required, the cost is high, which is a problem.

An object of the present invention is to provide an electronic component housing case that can effectively suppress a temperature rise of a heating element with a simple structure at low cost in view of the above points.

[0005]

According to a first aspect of the present invention, a circuit board on which an electronic component including a heating element is mounted is mounted on a case body. In a case for housing electronic components to be housed and fixed therein, the case body includes an upper case body and a lower case body having good heat conductivity, and extends one end of the upper case body or the lower case body The extension is brought into contact with the vicinity of the back surface of the circuit board corresponding to the mounting position of the heating element.

[0006] The above-mentioned extending portion is brought into contact with the vicinity of the back surface of the circuit board corresponding to the mounting position of the heating element without specially providing a component for suppressing the temperature rise of the heating element. Suppress temperature rise. That is, the heat generated from the heat generating element is transmitted to the case body of the upper case body or the lower case body via the substrate and the above-mentioned extending portion, thereby suppressing a temperature rise of the heat generating element.
Thus, it is possible to provide an electronic component housing case capable of effectively suppressing the temperature rise of the heating element with a simple structure that is low in cost.

According to a second aspect of the present invention, the circuit board is characterized in that its ends are pressed and fixed by the upper case body and the lower case body.

In this manner, the circuit board can be fixed to the case body by forming the end of the circuit board into a structure pressed by the upper case body and the lower case body.

According to the third aspect of the present invention, the upper case body is provided with a concave groove portion, and the end of the circuit board and the lower case body are pressed into the concave groove portion while being pressed with scissors. The body and the lower case body are integrally assembled.

As described above, the circuit board, the upper case body, and the lower case body are inserted into the recessed groove provided in the upper case body with the ends of the circuit board and the lower case body pressed and scissored. Can be assembled together.

According to the fourth aspect of the present invention, the extending portion has a shape having a spring property for generating a contact pressure to the circuit board when the extension portion is assembled between the upper and lower case bodies. There is a feature.

Since the extending portion has a spring-like shape to generate a contact pressure on the circuit board, the adhesion between the circuit board and the extending portion is enhanced, and the extending portion is moved from the circuit board side to the extending portion. Can increase the thermal conductivity. Therefore, the heat conducted from the heating element to the circuit board can be stably transmitted to the extending portion, and the temperature rise of the heating element can be effectively suppressed.

According to a fifth aspect of the present invention, there is provided a through hole penetrating the circuit board, and a heat conductor penetrating the through hole and conducting heat. And the second end is in contact with the extending portion.

Accordingly, the first end and the second end of the heat conductor are in contact with the heating element and the extending portion, respectively, and conduct heat from the heating element to the extending portion via the heat conductor. In this way, heat is conducted through the heat conductor that conducts heat,
The temperature rise of the heating element can be effectively suppressed.

[0015]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an electronic component housing case according to an embodiment of the present invention. The housing case of the present invention is configured by mounting a heating element such as a power transistor, a power MOS FET, or a power IC (an integrated circuit having a built-in power element) on a printed board serving as a circuit board or a ceramic board. The electronic control circuit parts for engine control and the like are housed inside. The structure of the storage case is devised as described below to suppress the temperature rise of the heating element.

FIG. 5 is an external perspective view showing an electronic control device using the storage case of the present invention. As shown in FIG.
The case body 1 is made of a metal such as aluminum having good heat conductivity or a resin having good heat conductivity. In this embodiment, the case body 1 is made up of an upper case body 2 and a lower case body 3. A connector that is connected to a printed circuit board described later inside the case body 1 and that inputs and outputs signals to and from electronic components including heating elements such as power transistors and power MOSs mounted on the printed circuit board. Seven.

Next, FIG. 1 shows a main part (partial sectional view) of the case body 1 as seen from the direction A in FIG. The heating element 5 is mounted on the surface of the printed circuit board 4, and an extension 3a is provided in which the end of the lower case body 3 extends inside the case body. The extension 3a is brought into contact with the vicinity of the back surface of the printed circuit board 4 corresponding to the mounting position of the heating element 5, specifically, the back surface position of the printed circuit board 4 opposite to the surface position of the heating element 5.

The extending portion 3a has a spring-like shape for generating a contact pressure with the printed circuit board 4. Specifically, the extension 3a of the lower case body 3 before the printed circuit board 4 and the lower case body 3 are joined together is a broken line portion 3a1 shown in FIG.
It has the shape of That is, when the both ends 41, 42 (see FIG. 4) of the printed board 4 are pressed and fixed by the upper and lower case bodies 2, 3, the printed board 4 and the lower case body 3 are fixed.
And a part of the printed circuit board 4 is extended
Is pushed down in FIG. Thereby, the extension 3a
Generates spring contact pressure with the printed circuit board 4 to increase the adhesion between the printed circuit board 4 and the extending portion 3a, thereby improving the thermal conductivity from the printed circuit board 4 side to the extending portion 3a. Is increasing.

In addition to the configuration of the lower case body 3 shown in FIG. 2, the configuration of the lower case body 13 shown in FIG. 3 may be adopted. FIG.
It is a fragmentary sectional view showing other examples of lower case object 13. In the lower case body 13, the configuration of the extending portion 3a having spring properties shown in FIG. 2 is changed. That is, the lower case body 13 shown in FIG.
3b, and is bent between the flat portion 13b and the extending portion 13a so as to have a spring property.
Thereby, the extending portion 13a having a spring property can be provided without being affected by an assembling force when the printed board 4 and the lower case body 13 are combined.

Then, as shown in FIG. 1, after the printed circuit board 4 and the lower case body 3 are fitted together, both ends 31, 32, 4 and 4 of the concave grooves 2b formed in the upper case body 2 are formed.
1 and 42 (see FIGS. 4 and 5) are fitted together. For details,
The printed circuit board 4, the lower case body 3 and the upper case body are pushed from the direction A in FIG. 5 along the concave groove 2b in a state where the both ends 31, 32, 41, 42 of the two 3, 4 are fitted together. This is the structure of the case body 1 in which the three members 2 can be integrated and assembled.

After the three members 2, 3, and 4 have been assembled, the caulking portion 2a of the upper case body 2 is swaged to eliminate the need for mounting and fixing parts such as screws. The case bodies 2 and 3 are formed by bending a metal plate material.
The processing of the extension 3a formed in the lower case body 3 and the concave groove 2b formed in the upper case body 2 is facilitated.

Next, the configuration of the printed circuit board 4 will be described with reference to FIG. FIG. 4 is a top view of the printed circuit board 4 in FIG. The heating elements 5 such as the power transistors 5a and the power MOSs 5b mounted on the printed board 4 are provided in a region where the printed board 4 and the extending portion 3a are in contact with each other as indicated by broken lines in FIG. 42.

The case 1 of the electronic control unit having the above-described structure.
The heat from the heating element 5 is transferred from the extending portion 3 a to the lower case body 3 and the upper case body 2 via the printed circuit board 4 without separately providing a component for suppressing the temperature rise of the heating element 5. And the heat is radiated from the entire surface of the case body 1 to effectively suppress the temperature rise of the heating element 5. As described above, it is possible to provide the electronic component housing case 1 that can effectively suppress the temperature rise of the heating element 5 with a simple structure that is low in cost.

(Modification) FIG. 6 is a partial sectional view showing the periphery of the heating element 5 according to a modification. FIG. 6 is different from FIG. 1 in that a heat conductor 8 that conducts the heat of the heating element 5 to the extending portion 3a side is disposed at the position of the printed circuit board 4 on which the heating element 5 is mounted. The heat conductor 8 is connected to the printed circuit board 4.
Is provided so as to penetrate through the inside of a through hole 4a formed through. The first end 8a and the second end 8b of the heat conductor 8 are in contact with the heating element 5 and the extension 3a, respectively, and the contact area is large so that the contact area with the heating element 5 and the extension 3a is large. Is composed by spreading. Of course, the first end 8a and the heating element 5 are in contact with each other in an electrically insulated state.

The structure of the heat conductor 8 is such that, for example, the solder is melted and poured into the through hole 4a, and the portion where the heating element 5 and the extending portion 3a are in contact with each other is enlarged so as to increase the contact area. The solder is adhered to the front and back surfaces of.

FIG. 7 is a bottom view of the printed circuit board 4 in FIG. 6 as viewed from below, and the heat conductor 8 is located within the installation area of the heating element 5 on the printed circuit board 4 (indicated by a broken line in FIG. 7). At least one.

In implementing the present invention, the heating element 5
The presence or absence of the above-described heat conductor 8 is selected according to the temperature rise situation of the above, and the temperature rise of the heating element 5 is suppressed.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view showing a main part of a case body of a control device as an electronic component housing case according to an embodiment of the present invention.

FIG. 2 is a partial sectional view showing a lower case body in FIG.

FIG. 3 is a partial sectional view showing another example of the lower case body.

FIG. 4 is a top view showing the printed circuit board in FIG. 1;

FIG. 5 is an external perspective view showing an electronic control device using the electronic component housing case of the present invention.

FIG. 6 is a partial cross-sectional view illustrating a periphery of a heating element according to a modification.

FIG. 7 is a bottom view of the printed circuit board in FIG. 6 as viewed from below.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Case body 2 Upper case body (a part of case body) 2b Concave groove part 3 Lower case body (a part of a case body) 3a Extension part 4 Printed circuit board (circuit board) 4a Through hole 5 Heating element 5a Power transistor (constituting a part of the heating element) 5b Power MOS FET (constituting a part of the heating element) 8 Thermal conductor 8a First end 8b Second end

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4E360 AB13 BC06 CA02 EA18 EA27 ED07 ED08 ED23 ED27 GA24 GB93 GB94 GB97 5E322 AA03 AA11 AB02 AB04 AB05 FA04 5E348 AA08 AA31 AA34

Claims (5)

[Claims] An electronic component storage case for mounting and fixing a circuit board on which an electronic component including a heating element is mounted inside a case body, wherein the case body has an upper case body and a lower case having good heat conductivity. And extending one end of the upper case body or the lower case body, and contacting the extended portion with the vicinity of the back surface of the circuit board corresponding to the mounting position of the heating element. A housing case for electronic components, wherein 2. The electronic component housing case according to claim 1, wherein said circuit board has an end pressed by said upper case body and said lower case body. 3. The circuit board, the upper case body and the upper case body are provided with a concave groove portion, and the end portion of the circuit board and the lower case body are pressed into the concave groove portion while being pressed. 3. The case for accommodating an electronic component according to claim 2, wherein the lower case body is assembled integrally. 4. The extension portion has a shape having a spring property to generate a contact pressure on the circuit board when the extension portion is assembled between the upper and lower case bodies. The electronic component storage case according to any one of claims 1 to 3, wherein: 5. A heat conductor which penetrates the circuit board and a heat conductor which penetrates the through hole and conducts heat, wherein the heat conductor has a first end in contact with the heat generating element, and a second heat conductor. The case for accommodating an electronic component according to any one of claims 1 to 4, wherein an end is in contact with the extending portion.