JPH08288681A - Cabinet for electronic apparatus and its manufacture - Google Patents

Abstract

PURPOSE: To accelerate heat conduction and increase rigidity, by selectively sticking and joining the surfaces of two plates to each other, forming a cabinet, and forming a flow channel of a heat pipe in the cabinet. CONSTITUTION: A cabinet is constituted by sticking and joining two plates 1, 2. In order to form a space turning to a flow channel of refrigerant between the two plates 1, 2, a heat pipe 3 is formed by locally deforming the inner plate 1 of the canibet. By the effect of this structure, the heat generated from elements of a CPU or the like is conducted as far as the cabinet through the heat pipe 3, and transferred to the whole surface of the heat pipe 3. Hence the temperature distribution is made uniform. The flow channel formed in the cabinet functions not only as the flow channel of refrigerant of the heat pipe 3 but also as rib structure which maintains rigidity of the cabinet. Thereby heat conduction is accelerated and further the rigidity is increased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a housing structure for electronic equipment and a method for manufacturing the same.

[0002]

2. Description of the Related Art When the amount of heat generated by an element such as a CPU mounted in an electronic device such as a workstation or a personal computer becomes enormous, forced air cooling using a fan to dissipate the heat (Japanese Patent Laid-Open No. 2- According to Japanese Patent Laid-Open No. 83958), there is proposed a method in which an existing heat pipe is stretched around and fixed to a housing to radiate heat from a wide housing. Further, although a structure in which a heat pipe is integrated inside a metal case has been proposed, a case structure that is lightweight and maintains high rigidity and can be manufactured has not been proposed.

[0003]

By forming a flow path of a heat pipe for taking in heat generated by the high heat generating element inside the housing, the heat is transferred to the entire surface of the housing to be radiated and formed at the same time. Achieves thinness and high rigidity by the flow path.

[0004]

In order to achieve the above object, the present invention has a structure in which plates are bonded together. The flow path is formed by bulging the unbonded portion of the two plates with high pressure gas or liquid pressure.

[0005]

With the above structure, the heat emitted from the CPU and other elements is carried to the housing by the heat pipe, and further transported to the entire surface of the housing by the integrated heat pipe formed in the housing, so that the temperature distribution is uniform. Be converted. In addition, the flow path formed in the housing acts as a rib structure for maintaining the strength of the housing in addition to the flow path for the heat pipe refrigerant.

[0006]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an electronic equipment casing according to the present invention having a heat pipe integral structure. That is, the housing is constructed by bonding two plates to each other, and the inner plate 1 of the housing is locally deformed to form a space serving as a refrigerant flow path between the two plates. 3 is formed. In this case, the heat pipe portion formed in a convex shape also serves as a rib that enhances the strength of the housing, and has both the features of promoting heat transfer and rigidity. Therefore, the thickness of each of the plate 1 and the plate 2 can be set to 1 mm or less. In addition, a structure with screw holes for suspending display devices such as circuit boards and liquid crystal displays inside the housing realizes a complicated housing shape that is almost the same as conventional plastic molded products and die-cast metal housings. It is possible.

FIG. 2 is a sectional view in the longitudinal direction near the center of the housing shown in FIG. The inner plate 1 and the outer plate 2 are joined together by a brazing material or an adhesive. A coolant such as water is sealed in the flow path of the heat pipe 3 for use.

Next, an example of the arrangement of the cooling system in the case of using the casing of the heat pipe integrated structure for electronic equipment will be described with reference to FIG. That is, the cooling system shown in FIG.
And the heat pipes 7 and 10 extending from the heat receiving plate, the heat pipe 3 and the flexible connectors 9 and 11 which are integrally formed in the housing on the display 8 side.
In FIG. 3, a case with a heat pipe integrated structure is used as a case part on the display side. The heat generated by the element 4 on the circuit board attached to the keyboard side is absorbed from the heat receiving plate 6 via the flexible contact. Due to the absorbed heat, the refrigerant enclosed in the heat pipe 7 on the keyboard side is vaporized and reaches the heat pipe 3 formed in the housing through the heat pipe 7 and the flexible connector 9. When the vaporized refrigerant passes through the heat pipe 3, it is cooled by heat radiation from the surface of the housing, so that the refrigerant changes from a gas to a liquid. The liquid refrigerant is the flexible connector 1
Returning to the heat receiving plate through 1 and the heat pipe 10, the same cycle is repeated thereafter. Here, in order to facilitate the flow of the vaporized refrigerant in the direction of the heat pipe 7 so that the circulation direction of the refrigerant is constant, the cross-sectional area of the heat pipe 7 is heated as shown in FIG. 6A. It may be larger than the cross-sectional area of the pipe 10. Further, as shown in FIG. 6 (b), stable circulation of the refrigerant can be obtained by always using the flow resistance nozzle 16 to facilitate the flow toward the heat pipe 7.

In the embodiment, the effect when the function as a heat pipe is taken into consideration is shown. However, the heat pipe integrated in the housing may be used as a coolant passage for circulating by a pump or the like. It is possible.

Next, an example of a process for processing the case integrated with the heat pipe shown in FIG. 1 will be described with reference to FIGS. 4 (a) to 4 (f). That is, as shown in FIG. 4A, two plates 1 and 2 are used, and a protrusion for inserting a rod 13 with a screw hole for fastening a display is formed on the plate 1 by pressing, and the plate 2 is formed. A release agent 21 such as ceramic powder is selectively applied or printed on the substrate so as to correspond to the shape of the heat pipe (FIG. 4B). Next, as shown in FIG. 4C, an adhesive such as a brazing material is inserted between the two plates, and the plates are superposed and then heat-treated to bond them. At this time, the two plates are not joined to the part where the release agent is applied. A rod 13 with a screw hole for fixing a circuit board or a display can be inserted and fixed in the burring projection hole at the same time. Next, as shown in FIGS. 4 (d) and 4 (e),
The outer peripheral skirt of the joined plates is molded by a die (composed of an upper punch 30, a wrinkle pressing punch 31, a die 32, and a lower punch 33) attached to a pressing device. After that, high-pressure air is introduced into the unbonded portion, and the inner plate 2 is stretched and formed. In this case, the amount of overhang is defined by the size of the recess 34 formed on the lower surface of the upper punch 30.

In the process, the two plates were joined by using the brazing material, but the joining by an adhesive is also possible. Further, in the embodiment, the passage of the heat pipe refrigerant is formed by introducing the high pressure gas at the final stage, but the passage is pressed at the stage of forming the rod 13 with screw holes, and then brazed. It is also possible.

Next, the connection relationship between the heat pipe formed on the display cover and each heat pipe that conducts heat from the element will be described in detail. 5A is a side view of the cooling system, and FIG. 5B is a top view. The heat pipes 7 and 10 having a wide width and a small thickness, the flexible connector 9 and the heat receiving plate 6 are adopted so as to achieve the thinning of the electronic device and not lower the cooling performance. That is, the cross section of each part is rectangular. The flexible connector 9 has a bellows structure rich in elasticity,
It can be easily deformed following the operation of opening and closing the display. Heat is transferred to the heat receiving plate 6 via the flexible contactor 15 having a good thermal conductivity such as silicon resin in the heat generating element 4 attached to the circuit board in FIG. 5A.
The heat receiving plate 6 and the heat pipes 7 and 10 can be joined by welding or brazing. Further, the heat pipe 7, the flexible connector 9 and the housing with the heat pipe can be joined by welding or brazing. The heat pipes 7 and 10, the flexible connector 9, the heat receiving plate 6,
The heat pipe 3 is made of stainless steel or aluminum,
Alternatively, a copper-based metal can be used. However, it is also possible to adopt a polymer flexible tube as the flexible connector, and a commercially available joint can be used for connection with the heat pipe.

FIG. 7 shows another example of a housing structure in which a heat pipe is integrated. Although the circulation type heat pipe flow path is formed in the housing shown in FIG. 1, the flexible connector is attached to only one place in FIG. 7 for connecting to the heat receiving plate. That is, FIG. 8 shows an arrangement state of the cooling system when the case shown in FIG. 7 is used. In this case, in the heat pipe 7, the refrigerant vaporized by the heat of the element moves to the heat pipe 3, and the refrigerant cooled in the casing and liquefied coexists. FIG. 9 shows how the heat pipes are connected to the heat receiving plate in this case. The refrigerant vaporized by the heat receiving plate 6 moves to the housing side along the upper part of the heat pipe 7, but the refrigerant liquefied by being cooled in the housing returns to the heat receiving plate along the lower part of the heat pipe 7, and the same cycle is performed. repeat.

In the embodiment, the heat pipe is formed only on the case on the display side, but it is also possible to form the heat pipe on the case on which the high heat generating element is mounted. The configuration of the cooling system in the case where a heat pipe is formed on the keyboard side casing will be described. That is, in FIG. 10, the heat generated by the high heat generating element 4 is transferred from the heat pipe 7 to the heat pipe formed in the keyboard side housing via the flexible connector 9. When the cooling system in FIGS. 3 and 8 is adopted, the flexible connector is subjected to bending deformation each time the display is opened and closed, so that the flexible connector is required to have high strength reliability. As shown in FIG. 10, if a case with a heat pipe is used on the side where the heating element is present, this problem can be solved. FIG. 11 shows the keyboard-side casing structure shown in FIG. 10. Like the display casing, the process shown in FIG. 4 is used to fix a circuit board, a hard disk, etc. with a screw hole rod 13. Can be formed. Further, in FIG. 11, the windows 60, 61 and 62 on the side wall of the housing for inserting the IC card and the floppy disk device can be formed by press punching or the like.

FIG. 12 shows a schematic mounting structure in which a heat generating element is inserted and fixed in a display side casing having a heat pipe. That is, the circuit board 40 in which the high heat generating element 4 is incorporated in addition to the display 8 is fixed to the housing, and then covered with the housing cover 17 on the display side. A connector 18 for electrically connecting the circuit board to the keyboard-side circuit board is formed. Further, the refrigerant can be inserted by filling the inside space of the heat pipe with the refrigerant, then sealing the mouthpiece portion 19 by pressure bonding, and then completely sealing by means such as welding. Although only one cap portion is shown in the figure, the provision of two caps facilitates the operation of charging the refrigerant.

Next, the means for transmitting the heat generated from the heating element to the heat pipe will be described with reference to the sectional view of FIG. That is, the heat from the element 4 is transferred to the heat pipe via the flexible contactor 15. By adopting the flexible contactor 15, it is possible to improve the heat transfer characteristics by making the element less likely to receive an impact from the outside and improving the adhesion with the element.

Although not described in the embodiment, it is possible to form a fine groove (wick) on the inner surface of the heat pipe by utilizing the capillary phenomenon so that the refrigerant can easily return to the heat receiving portion. Further, in the embodiment, the cooling system that transfers the heat from the element only to the case with the heat pipe of the present invention, but a part of the heat generation amount is transferred to the conventional case where the high heat generating element is mounted. If the heat is transferred and dispersed, it is possible to cool an element having a higher heating value.

As is apparent from the above embodiments, according to the present invention, it is possible to make the housing thinner while maintaining the rigidity of the housing, and it is possible to cool the high heat generating element by the integrated heat pipe.

[0020]

According to the present invention, it is possible to obtain an inexpensive heat pipe for efficiently transmitting heat from a high heat generating element such as a CPU to a small space of a notebook type workstation or a personal computer.

[Brief description of drawings]

FIG. 1 is a perspective view of a housing in which a heat pipe is integrated.

2 is a cross-sectional view of the housing of FIG.

FIG. 3 is a perspective view of an electronic device that incorporates a cooling system using the housing of the present invention.

FIG. 4 is an explanatory diagram of a heat pipe processing process.

FIG. 5 is an explanatory diagram of a cooling system.

FIG. 6 is an explanatory diagram of an element heat receiving portion.

FIG. 7 is a perspective view of a housing according to a second embodiment of the present invention.

FIG. 8 is a perspective view of an electronic device in which a heat pipe housing is mounted and a cooling system is incorporated.

FIG. 9 is an explanatory diagram of connection of heat pipes in the heat receiving unit.

[FIG. 10] A personal computer in which a cooling system is configured only by a keyboard side.

FIG. 11 is a perspective view of a keyboard-side housing in which a heat pipe is integrated.

FIG. 12 is an explanatory view of assembling components when a heat pipe is integrated with a display side casing.

FIG. 13 is a cross-sectional view of a means for transmitting heat from an element to a display-side housing integrated with a heat pipe.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Inner plate, 2 ... Outer plate, 3 ... Heat pipe channel, 13 ... Rod with screw hole.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical display location // B29L 22:00 31:34 (72) Inventor Yoshihiro Kondo 502 Jinmachi, Tsuchiura, Ibaraki Stock Company Hiritsu Manufacturing Co., Ltd. Mechanical Research Laboratory (72) Inventor Hitoshi Matsushima 1 Horiyamashita, Taino City, Kanagawa Prefecture

Claims (8)

[Claims] 1. A casing for an electronic device, wherein a surface of two plates is selectively bonded and joined to each other in the casing of the electronic device. 2. The electronic device casing according to claim 1, wherein at least one of the two plates is made of metal. 3. The housing for an electronic device according to claim 2, wherein a space is formed in an unjoined portion of the mating surfaces of the two plates to form a coolant flow path of the heat pipe. 4. The housing for electronic device according to claim 2, wherein a reinforcing rib of the housing is formed at an unjoined portion of the mating surfaces of the two plates. 5. A portable personal computer or workstation equipped with the housing according to claim 1, 2, 3 or 4. 6. The two plates are selectively joined by means such as a brazing material, an adhesive, welding or diffusion joining, and the joined plate is processed by press molding, and then the unjoined portion of the two plates is joined. A method of manufacturing a housing for an electronic device, which comprises plastically deforming liquid by means of liquid pressure or air pressure to form a flow path of a heat pipe. 7. The method according to claim 6, wherein the two plates are formed by means of press forming, and the unbonded portion of the two plates is formed by means of hydraulic or pneumatic means. A method for manufacturing a housing for an electronic device. 8. A method of manufacturing a housing for an electronic device, comprising: a step of joining a plate preliminarily formed with a protrusion by a pressing device to another plate; and forming a skirt portion on the outer periphery of the joined plate by pressing. .