JPH08298390A - Electronic apparatus - Google Patents

Abstract

PURPOSE: To provide a lightweight and low price electronic apparatus in which the heat generated from a heating body mounted on a circuit board can be dissipated effectively. CONSTITUTION: A part of a housing 11 is constituted of a cover 41 made of a material having high thermal conductivity. The cover partially touches a heating body 3 mounted on a board 2 and partially exposed to the outer air. A part of the housing 11 is composed of a material having high thermal conductivity and that part is brought into contact with the heating body in the housing so that the cover serves as a heat sink. When the cover is arranged to be exposed partially to the outside, the heat dissipation effect is accelerated through natural convection and the metal part is reduced without sacrifice of the heat dissipation effect for the heating body in the housing thus realizing cost reduction and weigh reduction of electronic apparatus. Furthermore, the cover is provided with fins 42 in order to enhance the heat dissipation effect.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic device, and more particularly to an electronic device having a substrate containing a heating element inside a housing.

[0002]

2. Description of the Related Art Conventionally, an electronic device having a substrate containing a heating element inside the housing is disclosed in US Pat. No. 4,571,456 in order to dissipate or disperse heat generated from the heating element inside the housing. The metal lower case is placed close to the heating element inside the housing, and this lower case is used as a heat sink. This will be described using a portable computer as a typical example. FIG. 7 is a side view of a general portable computer with a part cut away for the sake of explanation. For ease of explanation, it is assumed that there is only the heating element 3 attached to the substrate 2 inside the housing.

In the conventional method, in order to dissipate the heat generated from the heating element 3, the lower case 1 is made of a metal having a good thermal conductivity, and the heating element 3 is brought close to the surface of the lower case 1 so that The entire case 1 was used as a heat sink to dissipate or disperse the heat generated from the heating element 3.

[0004]

However, in the above-mentioned conventional example, since the lower case of the housing is used as a heat sink, the entire lower case of the housing has to be made of metal, resulting in high cost and heavy weight of electronic equipment. Become.
Further, there is a problem that the heat generated from the heating element is not sufficiently transmitted to the metal lower case only by bringing the metal lower case of the housing closer to the heating element inside the housing.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a lightweight and inexpensive electronic device capable of effectively radiating the heat generated from the heating element of the circuit board.

[0006]

In order to solve this problem, the present invention provides an electronic device having a substrate including a heating element inside a housing, wherein a part of the housing is made of a material having good thermal conductivity. A part of the member is in contact with the heating element and a part of the member is exposed to the outside air.

[0007]

In this structure, a part of the housing is made of a material having good thermal conductivity, and a part of the housing is brought into contact with the heating element inside the housing, so that the lid can be used as a heat sink. Also, by arranging a part of the lid so that it is exposed to the outside, the heat dissipation effect by natural convection is promoted, and
The weight portion can be reduced to reduce the cost and the weight of the electronic device without reducing the effect of dissipating the heat generated from the heating element inside the housing.

The member in contact with the heating element is formed as a lid that closes the opening of the housing, and the heating element inside the housing can be replaced by opening and closing the lid.

In order to further enhance the heat radiation effect, a radiation fin is provided on the member, and the radiation fin is arranged near the external connector. With this configuration, in addition to enhancing the heat dissipation effect, it is possible to eliminate the convex portion from the housing and improve the design.

Furthermore, when the external connector is supported by the above-mentioned member or part of the lid, the external connector mounting plate can be used as a heat sink in addition to the lid itself, so that the heat radiation effect is further improved and the housing is removed from the housing. The effect of improving the design by eliminating the convex portion can also be obtained. In this case, the same effect can be obtained even if the external connector mounting plate is made of a material having good thermal conductivity like the lid and is attached to the lid.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the embodiments shown in the drawings.

FIG. 1 is a diagram showing the outline of the external appearance of a portable computer which is an electronic device. A side view of the portable computer as seen from the direction of arrow A is shown in FIG. Further, details of the bottom surface of the portable computer as viewed in the direction of arrow B are shown in FIG. 3, and details of the rear interface connector section as viewed in the direction of arrow C are shown in FIG.

In FIG. 1, reference numeral 11 denotes a main body case which constitutes a housing of a portable computer. Various external connectors 61 to 66 are arranged on the back surface of the computer.

As is apparent from FIG. 2, a board 2 to which a heating element 3 is attached is arranged in the housing of the computer, and the circuit arranged on the board 2 is connected to an external connector via wiring 21 on the board 2. The connector 20 leading to 61 to 66 is attached.

As is apparent from FIG. 3, an opening is formed on the bottom surface of the housing 11, and the opening is closed by the lid 41. The lid 41 is, for example, a screw 5.
It is removably attached to the housing via 1 to 54. Further, the lid 41 is made of a material having better thermal conductivity than the housing, such as metal, and serves as a member forming a part of the housing, and as shown in FIG. 2, a part of the lid generates heat. It is arranged so as to come into contact with the body 3 and a part thereof is always exposed to the outside air. When a plurality of heating elements 3 are arranged on the substrate, each heating element is brought into contact with the lid 41.

In order to further enhance the heat radiation effect, a radiation fin 42 is provided on the lid 41, and this radiation fin 42 is
As shown in FIG. 4, the lid 41 is arranged so as to be exposed in the vicinity of the external connectors 61 to 66 on the back surface of the computer. The radiating fin is made of a material having a good thermal conductivity like the lid 41.

The transfer of heat generated from the heating element 3 in such a structure will be described with reference to FIG. 5 which schematically shows the inside of the portable computer. The movement path of the heat generated in the heating element 3 is divided into three: one that is transmitted to the contact portion due to the heat conduction effect, one that is diffused into the ambient air inside the housing by heat transfer, and one that is diffused to the surroundings by heat radiation. .

First, of the heat generated by the heating element 3, the heat conduction 81 to the substrate 2 on which the heating element 3 is mounted, the heat transfer 82 to the air inside the housing, and the radiation 83 to the surroundings are removed. The amount of heat is transferred from the contact portion with the lid 41 to the lid 4 by heat conduction 84.
1 and thus the lid 41 functions as a heat sink. Then, a part of the heat accumulated in the lid 41 is dissipated to the outside from the surface of the lid 41 exposed to the outside air (8
5). The movement route at this time depends on the usage state of the device. Then, the remaining heat is accumulated by the heat conduction 86 in the heat radiation fin 42 which is also connected to the lid 41 and also serves as a heat sink, and then is radiated from the heat radiation fin 42 to the outside air by the heat transfer 87 and the radiation 88. Through the above path, the heating element 3
It becomes possible to suppress the temperature rise.

As described above, in the embodiment of the present invention, by bringing the heating element 3 and the lid 41 into contact with each other, the heat generated in the heating element 3 is transferred to the lid 41 by the heat conduction effect, and the lid 4
By using 1 as a heat sink, heat can be diffused and the temperature rise of the heating element 3 can be suppressed. In addition, the lid 41 serves as a member forming a part of the housing, and one surface of the lid 41 is exposed to the outside.
It is possible to more efficiently dissipate the heat accumulated in the outside, and it is also effective in reducing the weight of equipment and reducing the housing cost.

Further, a part of the heat generated in the heating element 3 is transmitted through the lid 41 to the heat radiation fin 42 by the heat conduction effect, and is radiated from the heat radiation fin 42 to the outside air by heat transfer and heat radiation. The effect of suppressing the temperature rise of the heating element 3 can be enhanced. Further, by disposing the heat radiation fins 42 near the external connectors 61 to 66, the heat radiation fins 42 can be exposed to the outside air without protruding from the housing, so that the heat radiation effect can be improved without any disadvantage in design. It is possible.

Furthermore, since the lid 41 is constructed as a member for closing the opening formed in the housing, it is possible to replace the heating element or the circuit element attached to the circuit board by opening the lid. . In FIG. 3, the screws 51 to 54 are used to fix the housing 11 which is the main body case and the lid 41, but it goes without saying that the effect described above is not affected even if other fixing means is used.

In the above embodiment, the radiation fin 4
It is also possible to construct the lid 2 and the lid 41 as an integral member.

Next, another embodiment of the present invention is shown in FIG.
The shaded portion 7 in the drawing indicates an external connector mounting plate, which is made of metal or the like having good thermal conductivity and is normally exposed to the outside air. The external connector mounting plate 7 and the lid 41 are integrally made of the same material, or fixed by a method such as welding or screwing with a small thermal resistance. With this mounting plate, it is possible to obtain the same effect as that of the radiation fin 42.
That is, as in the case shown in FIG. 6, a part of the movement path of the heat generated in the heating element 3 is guided to the external connector mounting plate 7 by heat conduction, and is radiated to the outside air by heat transfer and heat radiation. As a result, the temperature rise of the heating element 3 can be suppressed.

[0024]

As described above, according to the present invention, a part of the housing is made of a member having a good thermal conductivity, and a part of this member is generated from the heating element by bringing it into contact with the heating element. It is used as a heat sink to dissipate heat, and by arranging part of this member so that it is exposed to the outside air, the heat dissipation effect by natural convection is promoted, and
The weight portion can be reduced to reduce the cost and the weight of the electronic device without reducing the effect of dissipating the heat generated from the heating element inside the housing.

Furthermore, when the member that contacts the heating element is formed as a lid that closes the opening of the housing, the heating element inside the housing can be replaced by opening and closing the lid. Is obtained.

In order to further enhance the heat radiation effect, a radiation fin is provided on the member, and the radiation fin is arranged near the external connector. With this configuration, in addition to enhancing the heat dissipation effect, it is possible to eliminate the convex portion from the housing and improve the design.

Further, when the external connector is supported by the above-mentioned member or part of the lid, the external connector mounting plate can be used as a heat sink in addition to the lid itself, so that the heat radiation effect can be further improved and the convex portion can be projected from the housing. It also has the effect of eliminating parts and improving the design.

[Brief description of drawings]

FIG. 1 is a perspective view showing an outline of an external appearance of a portable computer which is an electronic device.

FIG. 2 is a side view as seen from the direction of arrow A in FIG. 1, and is a side view in which a part of the side view is shown to show details.

FIG. 3 is a bottom view showing details of the bottom surface of the portable personal computer as seen from the direction of arrow B in FIG.

FIG. 4 is a rear view showing details of a rear interface connector section as viewed in the direction of arrow C in FIG.

FIG. 5 is an explanatory diagram for explaining a heat transfer path in the present invention.

FIG. 6 is a perspective view of a portable computer showing another embodiment of the present invention.

FIG. 7 is a partially cutaway side view of a conventional portable computer.

[Explanation of symbols]

 1, 11 Housing 2 Circuit board 3 Heating element 7 External connector mounting plate 41 Lid 42 Radiating fins 51-54 Fixing screws 61-66 External connector portion 81-88 Heat movement path

Claims (5)

[Claims] 1. An electronic device having a substrate containing a heating element inside a housing, wherein a part of the housing is made of a member of a material having good thermal conductivity, and a part of the member is in contact with the heating element. An electronic device characterized in that the parts are arranged so as to be exposed to the outside air. 2. The electronic device according to claim 1, wherein the member is configured as a lid that closes an opening of the housing. 3. The electronic device according to claim 1, wherein a radiation fin is provided on a part of the member. 4. The electronic device according to claim 3, wherein the heat radiation fin is arranged near an external connector. 5. The electronic device according to claim 1, wherein a part of the member supports an external connector.