JP3067090B2 - Radiator for electronic equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic device such as an AC adapter used as a power source for a small computer, and more particularly to a heat dissipation device.

[0002]

2. Description of the Related Art Recently, small computers called notebook computers have become widespread, and the operation power of such computers is configured to be supplied from an AC adapter. Such an AC adapter incorporates a power transformer for stepping down an AC voltage obtained from a commercial power supply, a diode for rectifying AC to DC, and the like. Since such an AC adapter is often carried together with a computer, it is required to reduce the size of the AC adapter.

[0003]

An electronic component such as a diode incorporated in an AC adapter generates a large amount of heat when power is supplied to a computer connected as a load. Therefore, in such an AC adapter, a heat radiating plate that emits heat generated from an electronic component is fixed to a printed wiring board in which the electronic component is incorporated, and a heat radiating operation is performed by bringing the heat radiating plate into contact with the electronic component. Is configured to do so.

When the shape of the AC adapter is reduced, the shape of the heat radiating plate also becomes smaller, which makes it difficult to sufficiently perform the heat radiation operation. As a result, the size of the AC adapter cannot be reduced. Was.

An object of the present invention is to provide a heat radiating device which solves such a problem.

[0006]

According to the present invention, there is provided a heat radiating device provided in a cabinet, on which a heat-generating electronic component is mounted, and wherein the electronic device is fixed to the printed wiring board and includes the electronic circuit. A heat radiating plate that contacts the component and emits heat generated from the electronic component; and a metal heat conducting member having a contact portion that contacts the heat radiating plate and a flat contact portion that contacts the flat portion of the cabinet. Have been.

[0007]

According to the present invention, the heat dissipating effect is enhanced by transmitting the heat of a heat radiating plate provided for contacting an electronic component and releasing heat generated from the electronic component to a cabinet by a heat conducting member. It is.

[0008]

FIG. 1 is an exploded perspective view showing a radiator according to the present invention.
FIG. 2 is a sectional view of a main part. In the figure, reference numerals 1 and 2 denote a lower cabinet and an upper cabinet constituting an electronic device, which are formed of resin and are connected to each other by tightening screws.

Reference numeral 3 denotes a support boss formed on the inner surface side of the flat bottom plate 1A constituting the lower cabinet 1. The support boss 3 has a screw hole through which the screw is inserted and a large-diameter support boss. A portion 3A and a small-diameter positioning portion 3B are provided. Reference numeral 4 denotes a printed wiring board in which an electronic circuit including an electronic component 5 that generates heat is incorporated. The printed wiring board 4 has support holes 6 and positioning holes 7 into which the positioning portions 3B of the support boss 3 fit.

Reference numeral 8 denotes a radiator plate which is attached to and fixed to the printed wiring board 4 so as to come into contact with the electronic component 5, and has mounting legs 8A and 8B formed in mounting holes 9 and 10 formed in the printed wiring board 4. It is configured to be fixed by being fitted into the. In addition, a concave portion 8C serving as a positioning function is formed at an upper end portion of the heat radiating plate 8, and a positioning through hole 8D is formed in a surface facing the back surface of the electronic component 5.

Reference numeral 11 denotes a heat conducting member made of a thin metal plate such as phosphor bronze, which is provided on a contact portion 11A for contacting the heat radiating plate 8 and an inner surface of a flat bottom plate 1A constituting the lower cabinet 1. It is composed of a planar contact portion 11B that makes contact. A positioning through hole 11C is formed at a position corresponding to the positioning through hole 8D formed in the heat radiating plate 8 of the contact portion 11A. A bent portion 11D that engages with the concave portion 8C is formed at a position corresponding to the positioning concave portion 8C formed on the heat radiating plate 8 of the contact portion 11A. Reference numeral 11E denotes a positioning bent piece formed in the heat conductive member 11, which is configured to fit into a positioning hole 7 formed in the printed wiring board 4. And the heat conductive member 11
Is configured to act as a shield member for an electronic circuit incorporated in the printed wiring board 4. That is, the heat conducting member 11 is so arranged as to cover the lower surface of the printed circuit board 4 in order to release heat, transmit the heat to the lower cabinet 1, and further increase the shielding effect. It is configured to increase the area of the planar contact portion 11B. A cutout 11F is formed at a position corresponding to the support boss 3 formed on the bottom plate 1A of the lower cabinet 1 of the heat conductive member 11.

A clamp member 12 has one end in contact with the front surface of the electronic component 5 and the other end in contact with the contact portion 11A of the heat conductive member 11, and the elastic force of the clamp member 12 causes the electronic component 5, the heat radiating plate 8 and the heat conductive member 11 to contact each other. It is configured to sandwich the contact portion 11A of the member 11. Further, a protrusion 12A is formed on the inner surface of the clamp member 12 which is in contact with the contact portion 11A of the heat conducting member 11 at a position facing the positioning through hole 11C, and the protrusion 12A is formed by the protrusion 12A. Hole 1
It is configured to be inserted into the positioning through hole 8D formed in the heat sink 8 through 1C.

Reference numeral 13 denotes a plane contact portion 1 of the heat conducting member 11.
1B and an insulating sheet provided between the printed wiring board 4 to prevent a short circuit between the circuit incorporated in the printed wiring board 4 and the heat conductive member 11; And the supporting boss 3
A positioning hole 14 into which the supporting portion 3A is fitted and a cutout portion 15 into which the positioning bent piece 11E formed in the heat conducting member 11 is fitted.

The present invention is configured as described above. Next, the assembling operation will be described. After assembling the electronic components 5 and the like into the printed wiring board 4, the mounting legs 8A and 8B formed on the heat sink 8 are respectively attached to the printed wiring board 4.
The heat radiating plate 8 is mounted and fixed to the printed wiring board 4 by being fitted into mounting holes 9 and 10 formed in the printed wiring board 4.
When such mounting is performed, the heat radiating plate 8 and the back surface of the electronic component 5 are brought into contact with each other. However, silicon grease or the like may be interposed between the heat radiating plate 8 and the back surface of the electronic component 5. I can do it.

While the insulating sheet 13 is interposed between the printed wiring board 4 assembled in this way and the heat conducting member 11, the bent portion 11D formed at the contact portion 11A of the heat conducting member 11 is formed. The bent piece 11E formed in the heat conductive member 11 is engaged with the concave portion 8C formed in the heat sink 8 and the bent piece 11E formed in the heat conductive member 11 is cut into the printed wiring board 4 through the cutout 15 formed in the insulating sheet 13. It is fitted into the formed positioning hole 7. Then, the printed wiring board 4, the insulating sheet 13 and the heat conductive member 11 assembled in this manner are placed on the bottom plate 1A of the lower cabinet 1, but at this time, the printed wiring board 4 is supported by the positioning holes 14 formed in the insulating sheet 13. The support portion 3A of the support boss 3 is fitted into the support hole 6 formed in the printed wiring board 4 while the support portion 3A of the support boss 3 is fitted. Therefore, the supporting operation of the printed wiring board 4 and the positioning operation of the printed wiring board 4, the insulating sheet 13, and the heat conducting member 11 are performed.

After such an assembling operation is performed, all the components can be assembled by mounting the clamp member 12 so as to sandwich the electronic component 5, the heat sink 8, and the heat conducting member 11. When performing such an operation, if the protrusion 12A formed on the clamp member 12 is inserted into the positioning through hole 11C formed on the heat conductive member 11, the protrusion 12A is formed on the heat sink 8. Inserted into the positioning through hole 8D. Therefore, the positioning operation of the clamp member 12 is performed. In such a state, if all the surfaces of the clamp member 12 facing the heat conductive member 11 are configured to contact the heat conductive member 11, the elastic force of the clamp member 12 against the surface of the heat conductive member 11 Are uniformly applied, so that a good contact state can be maintained. When the upper portion 12B of the clamp member 12 is configured to be in contact with the bent portion 11D formed on the heat conducting member 11, the positioning of the clamp member 12 is performed more accurately by cooperation with the protrusion 12A. I can do it.

As described above, the assembling operation of the printed wiring board 4, the insulating sheet 13 and the heat conducting member 11 with respect to the lower cabinet 1 is performed. In this state, the upper cabinet 2 is engaged with the lower cabinet 1 to support the lower cabinet 1. If a screw is inserted into a screw hole formed in the boss 3 to perform a tightening operation, the assembly of the electronic device can be completed.

In the electronic device assembled as described above, when heat is generated from the electronic component 5, the heat is generated by the heat sink 8.
And to the heat conducting member 11 which is in contact with the heat radiating plate 8. The heat transmitted to the heat conduction member 11 is transmitted from the contact portion 11A of the heat conduction member 11 to the flat contact portion 11B. As a result, since the flat contact portion 11B is in contact with the bottom plate 1A of the lower cabinet 1, the heat transmitted to the flat contact portion 11B is transmitted to the bottom plate 1A of the lower cabinet 1. Therefore, the heat generated from the electronic component 5 is radiated from the radiator plate 8, the heat conducting member 11 and the lower cabinet 1.

[0019]

According to the heat radiating device of the present invention, the heat of the heat radiating plate fixed to the printed wiring board on which the electronic component is mounted and which comes into contact with the rear surface of the electronic component and emits the heat generated from the electronic component is provided. Is provided as means for transmitting the printed circuit board to the cabinet, and a positioning bent piece is provided on a metal heat conducting member that shields an electronic circuit, and the bent piece is provided with a positioning hole formed in the printed wiring board and the printing. The printed wiring board and the insulating sheet, and the positional relationship between the heat conductive member was defined by fitting into a cutout formed in the wiring board and the insulating sheet, so that the printed wiring board, the insulating sheet, And the positional relationship with the heat conducting member can be accurately maintained. Therefore, according to the present invention, it is possible to accurately and easily perform a process of incorporating each component into a miniaturized electronic device.

[0020]

[0021]

[0022]

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing one embodiment of a heat dissipation device of the present invention.

FIG. 2 is a sectional view of a main part showing a heat dissipation device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lower cabinet 4 Printed wiring board 5 Electronic component 8 Heat sink 11 Heat conduction member 11A Contact part 11B Plane contact part 12 Clamp member 13 Insulation sheet

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-111580 (JP, A) JP-A-60-136195 (JP, U) JP-A-5-33687 (JP, U) JP-A-61-1 27345 (JP, U) Japanese Utility Model Application Hei 5-76090 (JP, U) Japanese Utility Model Application Hei 4-131990 (JP, U) Japanese Utility Model Application Hei 3-53892 (JP, U) (58) Fields surveyed (Int. ⁷ , DB name) H05K 7/20 H05K 9/00

Claims (1)

(57) [Claims] 1. A printed wiring board provided in a cabinet constituting an electronic device and having an electronic component generating heat mounted thereon, and fixed to the printed wiring board and in contact with a rear surface of the electronic component. A heat radiating plate for emitting heat generated from the electronic component, a contact portion having an inner surface in contact with the heat radiating plate, and a flat contact portion in contact with a flat plate portion forming the cabinet , and incorporated in the printed wiring board;
Metal heat-conducting member that shields electronic circuits
Between the planar contact portion of the heat conductive member and the printed wiring board
Insulation sheet with heat-resistant properties placed between
And one end is in contact with the front of the electronic component and
The end abuts on the outer surface of the contact portion of the heat conducting member,
Contact between the component and the heat sink and between the heat sink and the heat conducting member
And a clamp member for elastically touching the heat conductive member.
A positioning bent piece is provided on the member, and the bent piece is connected to the printed wiring.
Positioning holes formed in the substrate and the insulating sheet
The printing is performed by fitting into the cutout formed.
Wiring board and the insulating sheet, and the heat conductive member
A heat radiating device for electronic equipment, wherein a positional relationship is defined .