JP2009073314A - Case for on-vehicle electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a case for on-vehicle electronic equipment, which promotes heat radiation. <P>SOLUTION: This case 1 is provided with: a main body 2; a printed board 7 mounted on the main body 2 so as to be located on a rear face of the main body 2; a plurality of heating parts 72 mounted on the printed board 7 so that a heating surface is located on the side of a rear face of the printed board 7; a cover 4 having a plurality of projecting portions 41, covering the whole of the rear face of the printed board 7, formed by synthetic resin with better thermal conductivity than that of air, and mounted on the main body 2; and thermally conductive rubber 10 with better thermal conductivity than that of air, interposed between the projecting portions 41 and the heating parts 72. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

    The present invention relates to an on-vehicle electronic device case, and more particularly to an on-vehicle electronic device case that can promote heat dissipation in a main body.

    2. Description of the Related Art Conventionally, in order to dissipate heat from a case for an in-vehicle electronic device, for example, a vehicle meter case, an opening is provided in the vehicle meter case, and heat is allowed to enter and exit through the opening.

    However, there is a problem that the above-mentioned opening part may cause failure of electronic components in the vehicle meter case because moisture, air, dust, and the like enter in addition to heat input and output.

    An object of this invention is to provide the case for vehicle-mounted electronic devices made in consideration of said point.

    The in-vehicle electronic device case of the present invention includes a main body, a printed circuit board attached to the main body so as to be positioned on the back surface of the main body, and the heat generating surface positioned on the back surface side of the printed circuit board. A plurality of heat generating components attached to the substrate, a cover having a plurality of convex portions, covering the entire back surface of the printed circuit board and made of synthetic resin having better thermal conductivity than air, and a cover attached to the main body; A heat conductive rubber having better heat conductivity than air is interposed between the convex portion of the cover and the heat generating component.

    The case for in-vehicle electronic equipment according to claim 2 is such that the main body, the printed circuit board attached to the main body so as to be positioned on the back surface of the main body, and the heat generating surface located on the back surface side of the printed circuit board. A synthetic resin having a plurality of heat generating components attached to the printed circuit board and a plurality of convex portions contacting the plurality of heat generating components, covering the entire back surface of the printed circuit board and having better thermal conductivity than air And a cover attached to the main body.

    According to a third aspect of the present invention, there is provided an in-vehicle electronic device case according to the first or second aspect, wherein the printed circuit board and the cover are brought into contact with each other.

    The on-vehicle electronic device case according to claim 4 is the on-vehicle electronic device case according to any one of claims 1 to 3, and is more thermally conductive than air in a gap between the cover and the printed circuit board. Good synthetic resin or rubber is interposed.

    A case for an in-vehicle electronic device according to claim 5 is the case for an in-vehicle electronic device according to any one of claims 1 to 4, wherein the cover is provided on a surface opposite to the side facing the printed circuit board. The heat dissipating fins are provided.

    The on-vehicle electronic device case according to claim 6 is the on-vehicle electronic device case according to claim 2, wherein the cover is thermally conductive from air having a shape that conforms to the concavo-convex shape on the back surface of the printed circuit board. It is made of a synthetic resin with good properties.

    The on-vehicle electronic device case according to claim 7 has a main body, a printed circuit board attached to the main body so as to be positioned on the back surface of the main body, and a heating surface positioned on the back surface side of the printed circuit board. In addition, a plurality of heat generating components attached to the printed circuit board and a synthetic resin having better thermal conductivity than air having a shape that conforms to the uneven shape on the back surface of the printed circuit board, and attached to the main body And a heat conductive rubber which is located between the plurality of heat generating components and the cover and has better heat conductivity than the air abutting on each cover.

    According to the on-vehicle electronic device case according to claim 1, since the heat conductive rubber having better heat conductivity than air is interposed between the convex portion of the cover and the heat generating component, the heat conductive rubber, the cover The heat of the heat generating component is conducted to the cover through the convex portion of the cover to promote heat dissipation of the heat generating component, and the printed circuit board is supported by the convex portion of the cover via the heat generating component. In order to prevent bending, it is possible to prevent disconnection of the printed circuit board due to bending, and to interpose a heat conductive rubber having better thermal conductivity than air between the convex portion of the cover and the heat generating component, The heat of the heat generating component can be transmitted to the cover in such a manner that no gap occurs in contact with the heat generating component.

    According to the on-vehicle electronic device case according to claim 2, the plurality of convex portions of the cover are brought into contact with the plurality of heat generating components, and the heat of the plurality of heat generating components is transmitted through the plurality of convex portions. In addition to promoting heat dissipation of the heat generating component, the printed circuit board is supported by the plurality of convex portions through the plurality of heat generating components, preventing the printed circuit board from being bent and preventing the printed circuit board from being disconnected due to the bending. can do.

    According to the on-vehicle electronic device case of claim 3, in addition to the effect of the invention of claim 1 or 2, the heat of the printed circuit board is transmitted to the cover in order to bring the printed circuit board into contact with the cover. Can be made.

    According to the on-vehicle electronic device case according to claim 4, in addition to the effects of the inventions according to claims 1 to 3, in the gap between the cover and the printed circuit board, the heat conductivity is better than that of air Since the resin or rubber is interposed, the heat of the printed circuit board can be transmitted to the cover through the synthetic resin or rubber having better thermal conductivity than air.

    According to the on-vehicle electronic device case according to claim 5, in addition to the effects of the inventions according to claims 1 to 5, the radiating fin is provided on the surface of the cover opposite to the side facing the printed circuit board. Therefore, the heat dissipation effect can be promoted.

    According to the on-vehicle electronic device case according to claim 6, in addition to the effect of the invention according to claim 2, the cover has an air having a shape that entirely matches the uneven shape of the back surface of the printed circuit board. Since it is formed of a synthetic resin having better thermal conductivity, the heat of the printed circuit board can be transmitted to the cover.

    According to the on-vehicle electronic device case according to claim 7, the cover is formed of a synthetic resin having better thermal conductivity than air having a shape that conforms to the concave-convex shape on the back surface of the printed circuit board. Therefore, the heat of the printed circuit board can be transmitted to the cover, and the heat conductive rubber having better heat conductivity than air is interposed between the cover and the heat generating component. The heat of the heat generating component is conducted to the cover to promote heat dissipation of the heat generating component, and the printed circuit board is supported by the cover via the heat generating component to prevent the printed circuit board from being bent. The circuit board can be prevented from being disconnected, and a heat conductive rubber having better heat conductivity than air is interposed between the cover and the heat generating component. As gap does not occur, it is possible to transfer heat of the heat generating component on the cover.

An embodiment of a case for an in-vehicle electronic device according to the present invention will be described with reference to the drawings.
1 to 3, reference numeral 1 denotes an in-vehicle electronic device case, for example, a vehicular meter case. As shown in FIG. 2, the vehicular meter case 1 has a main body 2 positioned at the center and a main body (case) 2. A glass 3 is located in front of the main body 2 and a cover 4 is located behind the main body 2.

A dial plate 5 is attached so as to be positioned on the surface of the main body 2. The dial 5 has, for example, a speedometer character at the center, a tachometer character to the left of the speedometer character, and a fuel gauge character to the right of the speedometer character.
6 is a guideline. Reference numeral 7 denotes a printed circuit board in which a wiring pattern is drawn with copper foil on a highly insulating glass fiber reinforced epoxy resin substrate and electronic components such as resistors and LSIs are mounted. In order to improve heat conduction, the printed circuit board 7 includes a metal core, for example, a copper core 71. The printed circuit board 7 is attached to the main body 2 so as to be positioned on the back surface of the main body 2.
Reference numeral 72 denotes a heat generating component attached to the printed circuit board 7 so that the heat generating surface is located on the back surface side of the printed circuit board 7. The heat generating component 72 includes, for example, an integrated circuit, a semiconductor component, Stepping motors, power transistors for controlling rotation and stopping of stepping motors, and the like.

The cover 4 has a plurality of convex portions 41, covers the entire back surface of the printed circuit board 7, and is formed of a synthetic resin (for example, polypropylene) having better thermal conductivity than air. It can be attached. Since the printed circuit board 7 and the cover 4 are in contact with each other, the heat of the printed circuit board 7 can be transmitted to the cover 4.
The cover 4 is formed of a synthetic resin (for example, polypropylene) having better thermal conductivity than air. Preferably, the thermal conductivity improver is made of magnesium hydroxide having a specific property capable of imparting high thermal conductivity to the synthetic resin. And those in which a metal oxide such as aluminum oxide is kneaded with a synthetic resin such as epoxy or urethane is preferable.
Further, between the convex portion 41 of the cover 4 and the heat generating component 72, the heat conductive rubber 10 having better heat conductivity than air is interposed. This is because the heat of the heat generating component 72 is reliably transmitted to the cover 4 so that there is no gap in the contact between the convex portion 41 of the cover 4 and the heat generating component 72.
The heat conductive rubber 10 having a heat conductivity higher than that of air is, for example, silicone rubber. Preferably, a rubber such as silicone rubber or EPDM is filled with a heat conductive filler and kneaded and molded. .
Further, on the surface of the cover 4 opposite to the side facing the printed circuit board 7, a plurality of heat radiating fins 44 for promoting a heat radiating effect are arranged in parallel.

Therefore, according to the vehicle meter case 1 described above, the heat conductive rubber 10 is interposed between the convex portion 41 of the cover 4 and the heat generating component 72 so that the heat conductive rubber 10 having better heat conductivity than air is interposed. The heat of the heat generating component 72 is conducted to the cover 4 through the convex portion 41 of the cover 4 and the heat dissipation of the heat generating component 72 can be promoted.
Moreover, since the printed circuit board 7 is supported by the convex part 41 of the cover 4 via the heat generating component 72, it is possible to prevent the printed circuit board 7 from being bent and to prevent disconnection of the printed circuit board 7 due to the bending.

Desirably, as described above, the thermal conductive rubber 10 that also relieves vibration is interposed between the convex portion 41 of the cover 4 and the heat generating component 72. However, as shown in FIG. The heat conductive rubber 10 may be omitted, and the convex portion 41 of the cover 4 and the heat generating component 72 may be brought into contact with each other.
In the vehicle meter case 1 shown in FIG. 4, the plurality of convex portions 41 of the cover 4 are brought into contact with the plurality of heat generating components 72 to cover the heat of the plurality of heat generating components 72 via the plurality of convex portions 41. 4 to promote heat dissipation of the heat generating component 72, and the printed circuit board 7 is supported by the plurality of convex portions 41 via the plurality of heat generating components 72 to prevent the printed circuit board 7 from being bent. Can be prevented.

    In the above-described embodiment, a gap is formed between the cover 4 and the printed circuit board 7, and air is present in the gap, so that the heat dissipation effect is hindered. As shown in FIG. 5 and FIG. 6, rubber 20 (or a synthetic resin having better heat conductivity than air) may be interposed, as shown in FIG. 4 may be formed of a synthetic resin having better thermal conductivity than air having a shape that conforms to the uneven shape of the back surface of the printed circuit board 7 as a whole, and as shown in FIG. The cover 4 is formed of a synthetic resin having better heat conductivity than air having a shape that conforms to the concave and convex shape on the back surface of the printed circuit board 7, and the cover 4 is attached to the main body 2. Better thermal conductivity than air Positions the conductive rubber 10, the heat-conducting rubber 10 may be in contact with each heat generating component 72 and the cover 4. Further, in FIG. 8, the heat conductive rubber 10 having better heat conductivity than air is positioned between the plurality of heat generating components 72 and the cover 4, although not shown, the cover 4 and the printed circuit board 7 are not illustrated. A heat conductive rubber 10 having better heat conductivity than air may be positioned between them.

FIG. 1 is a schematic exploded perspective view of a case for an in-vehicle electronic device. 2 is a schematic exploded perspective view of the in-vehicle electronic device case of FIG. 1 as seen from the back side of the in-vehicle electronic device case of FIG. FIG. 3 is a schematic cross-sectional view showing a state where the on-vehicle electronic device case of FIG. 1 is assembled. 4 is a schematic cross-sectional view of an in-vehicle electronic device case of another embodiment different from the in-vehicle electronic device case of FIG. FIG. 5 is a schematic cross-sectional view of an in-vehicle electronic device case of another embodiment different from the in-vehicle electronic device case of FIG. 6 is a schematic cross-sectional view of an in-vehicle electronic device case of another embodiment different from the in-vehicle electronic device case of FIG. FIG. 7 is a schematic cross-sectional view of an in-vehicle electronic device case of another embodiment different from the in-vehicle electronic device case of FIG. FIG. 8 is a schematic cross-sectional view of an in-vehicle electronic device case of another embodiment different from the in-vehicle electronic device case of FIG.

Explanation of symbols

1 Car electronics case (vehicle meter case)
2 Body 4 Cover 41 Convex 7 Printed circuit board 10 Thermally conductive rubber

Claims (7)

The body,
A printed circuit board attached to the main body so as to be located on the back surface of the main body;
A plurality of heat generating components attached to the printed circuit board so that the heat generating surface is located on the back side of the printed circuit board;
A cover having a plurality of convex portions, covering the entire back surface of the printed circuit board, formed of a synthetic resin having better thermal conductivity than air, and attached to the main body,
A case for in-vehicle electronic equipment, wherein a heat conductive rubber having better heat conductivity than air is interposed between the convex portion of the cover and the heat generating component. The body,
A printed circuit board attached to the main body so as to be located on the back surface of the main body;
A plurality of heat generating components attached to the printed circuit board so that the heat generating surface is located on the back side of the printed circuit board;
A plurality of convex portions that come into contact with the plurality of heat-generating components, cover the entire back surface of the printed circuit board, and are formed of a synthetic resin having better thermal conductivity than air, and a cover attached to the main body,
An in-vehicle electronic device case characterized by comprising: The case for in-vehicle electronic equipment according to claim 1 or 2, wherein the printed circuit board and the cover are brought into contact with each other. The in-vehicle electronic device case according to any one of claims 1 to 3, wherein a synthetic resin or rubber having better thermal conductivity than air is interposed in a gap between the cover and the printed board. The case for in-vehicle electronic devices according to any one of claims 1 to 4, wherein a radiation fin is provided on a surface of the cover opposite to the side facing the printed circuit board. The in-vehicle electronic device case according to claim 2, wherein the cover is formed of a synthetic resin having a heat conductivity higher than that of air having a shape that conforms to the uneven shape on the back surface of the printed board. The body,
A printed circuit board attached to the main body so as to be located on the back surface of the main body;
A plurality of heat generating components attached to the printed circuit board so that the heat generating surface is located on the back side of the printed circuit board;
A cover that is formed of a synthetic resin having better thermal conductivity than air having a shape that conforms to the uneven shape on the back surface of the printed circuit board, and is attached to the main body;
A heat conductive rubber which is located between the plurality of heat generating components and the cover and has better heat conductivity than the air abutting on each of them;
An in-vehicle electronic device case characterized by comprising:

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