JPH0579779A - Heat pipe type cooler - Google Patents

Abstract

PURPOSE:To obtain a cooler having a heat pipe, in which its bent part can be easily formed, while maintaining a strength necessary to mount a heat radiator by providing a heat radiation part having a hardness necessary to mount a heat radiating fin and a softer bent part than the radiation part at the pipe. CONSTITUTION:Both ends 1b, 1c of a heat pipe 1 each has a size and a hardness necessary to mount a heat radiator of a housing side plate 21, and a bent part 1a interposed to be held between both the eras 1b and 1c is soft so as to bend the part 1a. A metal pipe to be used for the heat pipe entirely has a hardness necessary to mount the radiator in such a manner that the part corresponding to the bent part can be bent by high frequency induction heating. Accordingly, the plate 21 of the radiator can be easily and effectively mounted. The bent part is easily bent, and a limit of smaller radius of curvature when the pipe is bent can be increased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat pipe type cooler using a heat pipe having a bent portion.

[0002]

2. Description of the Related Art A heat pipe cooler used for cooling a semiconductor element is provided with a heat source such as a semiconductor element at one end of a heat pipe made of a metal tube to serve as a heat input portion. A heat radiating member such as a heat radiating fin is attached to the end portion to form a heat radiating portion. The shape of the heat pipe used for this cooler is specified according to the relationship between the direction of the heat source and the direction of the heat radiator.If the direction of the heat source and the direction of the heat radiator are different, the heat pipe The portion sandwiched between the heat portion and the heat radiation portion is bent.

Conventionally, in a cooler using a heat pipe having such a bent portion, as a heat pipe, a heat pipe that has been conditioned to have a hardness necessary for attaching a radiator to the radiator is used. That is, in order to securely attach a radiator such as a metal radiator fin to the heat pipe,
The heat pipe is required to have the hardness necessary to withstand this attachment. Therefore, conventionally, the entire heat pipe is set to the same hardness based on this hardness.

[0004]

However, when the heat pipe as a whole is set to the hardness necessary for mounting the heat radiator, this hardness becomes a great resistance in bending the heat pipe. That is, a dedicated processing machine is used to bend the heat pipe, but if the entire heat pipe has the hardness necessary for mounting the radiator, the portion to be bent of the heat pipe is hard, The process of bending the heat pipe is very difficult, and the bending process requires a large amount of work and a long time.

Moreover, since it is difficult to bend the heat pipe, there is a limit to reducing the radius of curvature at the bent portion of the heat pipe, and the heat pipe cannot be bent with a too small radius of curvature.

Therefore, it has been considered to make the entire heat pipe hard enough to bend, but in this case, there is a problem that it becomes difficult to securely attach the heat radiator to the heat pipe.

It is also conceivable to form the bent portion of the heat pipe into a bellows shape, but in this case, the process of forming the heat pipe into a bellows is very difficult and not practical.

The present invention has been made in view of the above circumstances, and provides a heat pipe type cooler having a heat pipe that maintains the strength required for mounting a radiator in the heat radiating portion and is easily bent in the bent portion. The purpose is to

[0009]

In order to achieve the above-mentioned object, a heat pipe type cooler of the present invention is provided with a heat source at one end of the heat pipe to serve as a heat input portion, and at the other end of the heat pipe. Is a heat sink by attaching a heat sink, and the heat pipe part sandwiched between the heat input part and the heat sink part is bent, and the heat sink part of the heat pipe has the hardness necessary for mounting the heat sink. The bent portion of the heat pipe is softer than the heat radiating portion.

[0010]

Since the heat radiating portion of the heat pipe has the hardness required to attach the heat radiator, the heat radiator can be easily and surely attached.

Since the bent portion of the heat pipe is softer than the heat radiating portion, the bending process is easy, and the limit of the smaller bending radius can be expanded.

Further, the heat treatment for softening the bent portion of the heat pipe may be a heat treatment, but this heat treatment is very simple and requires no trouble.

[0013]

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

An embodiment of the heat pipe type cooler of the present invention will be described with reference to FIG.

This embodiment is applied to a heat pipe cooler for cooling semiconductor elements in electronic equipment. Specifically, the present invention is applied to a heat pipe type cooler in which a semiconductor element provided inside a housing of an electronic device is used as a heating element and a side plate of the housing is used as a radiator.

In the figure, reference numeral 21 denotes a side plate which constitutes a side portion of the housing of the electronic device, and the housing side plate 21 is formed of a metal plate. Reference numeral 22 denotes a wiring board horizontally provided inside the housing surrounded by the housing side plate 21.

The heat pipe cooler will be described.

In the figure, reference numeral 1 denotes a heat pipe, which is a round pipe made of a metal material with both ends closed. Examples of the metal forming the heat pipe 1 include copper. The heat pipe 1 is bent at a substantially right angle with the middle portion being a bent portion 1a, one end portion 1b is positioned horizontally, and the other end portion 1c is positioned vertically.

The bent portion 1 of the heat pipe 1
The other parts except a have a hardness of a size necessary for attaching a heat radiator as described later, and the bent portion 1a is softer than the hardness of other parts and has a size that can be easily bent. It has the hardness of That is, both ends 1b, 1c of the heat pipe 1 have a hardness of a size required for attaching the heat radiator, and the bent portion 1 sandwiched between the ends 1b, 1c.
“A” is soft to allow bending.

At one horizontal end 1b of the heat pipe 1, a metal block 3 having a semiconductor element 2 as a heat source mounted therein is fitted and attached. Examples of the metal forming the metal block 3 include aluminum. As a result, a heat input section is formed at the horizontal end of the heat pipe 1.
The semiconductor element is electrically connected to the circuit formed on the surface of the wiring board 22.

The other vertical end 1c of the heat pipe 1 is contacted along the vertical surface of the housing side plate 21, and is further pressed by the holding metal fitting 4 and fixed to the housing side plate 21.
That is, the holding metal fitting 4 is fixed to the housing side plate 21 with the screw 5. Here, the housing side plate 21 serves as a radiator.

In the heat pipe type cooler having the above structure, the heat pipe 1 is manufactured as follows.

A metal pipe cut into a predetermined length is prepared. The metal pipe as a whole has the hardness necessary for attaching the heat radiator. Squeeze one end of the metal pipe to close it.
Next, a portion corresponding to the bent portion of the metal pipe is subjected to high frequency induction heating treatment to have a hardness that allows bending. This heat treatment is very simple and requires no effort. Further, a machine is used to bend the metal pipe around the bent portion. Excluding the air inside the metal pipe, the working fluid, for example water, is put inside. After that, the other end of the metal pipe is squeezed and closed, and the working fluid is sealed inside the metal pipe.

After the working fluid is put into the metal pipe and the other end of the metal pipe is squeezed and closed to form a heat pipe, the heat treatment is performed while the metal pipe is being cooled to be bent. good.

The heat pipe type cooler of this embodiment has the following effects.

Since the heat radiating portion of the heat pipe 1 has a hardness necessary for attaching the heat radiating body, the housing side plate 21 which is the heat radiating body can be easily and surely attached. Further, since the bent portion of the heat pipe 1 is softer than the heat radiating portion, the bending process is easy, and the smaller limit of the radius of curvature when bending the heat pipe 1 is expanded as compared with the conventional one. can do.

A specific example of the heat pipe 1 will be described.
A pure copper pipe is used for the metal pipe. The heat pipe 1 has an outer diameter of 12.7 mm, a wall thickness of 0.5 mm, a total length of 250 mm, a heat input portion length of 50 mm, a heat radiation portion length of 150 mm, and a bent portion length of 5.
The radius of curvature is 0 mm and the bending radius is 30 mm. Here, the curvature radius of the bent portion is set to 30 mm, because the pipe can be easily bent,
Moreover, the pipe is less likely to be flat due to bending.

The heat radiating portion of the heat pipe 1 has a Vickers hardness (Hv) 111, and the bent portion has a Vickers hardness of 49.

FIG. 2 shows another embodiment. 2, the same parts as those in FIG. 1 are designated by the same reference numerals. In this embodiment, the heat pipe 1 is arranged horizontally instead of standing vertically, the metal block 3 is attached to one end 1b, and a plurality of heat radiation fins 6 are attached to the other end 1c as heat radiators. Also in this embodiment, the same effect as the above-mentioned embodiment can be obtained.

FIG. 3 shows another different embodiment. In this embodiment, the metal block 3 is attached using the central portion of the heat pipe 1 as a heat input portion, and the heat radiation fins 6 are attached to both ends of the heat pipe 1 as heat radiation portions.
Then, the metal block 3 of the heat pipe 1 and one heat radiation fin 6 and the metal block 3 and the other heat radiation fin 6 are bent at right angles as bent portions 1a and 1a, respectively.

The present invention is not limited to the above-mentioned embodiments, but can be modified in various ways.

For example, the heat pipe cooler of the present invention is
It is not limited to the use for cooling the semiconductor element, but can be widely used for other uses.

[0033]

As described above, according to the heat pipe type cooler of the present invention, the heat dissipating portion of the heat pipe has a hardness necessary for mounting the heat dissipating body, and the bent portion of the heat pipe becomes the heat dissipating portion. Since it is soft in comparison, it is possible to easily form the bent portion of the heat pipe while maintaining the strength required for attaching the radiator in the heat pipe.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a heat pipe type cooler of the present invention.

FIG. 2 is a perspective view showing another embodiment of the heat pipe type cooler of the present invention.

FIG. 3 is a perspective view showing another embodiment of the heat pipe type cooler of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Heat pipe, 2 ... Semiconductor element, 3 ... Metal block, 4 ... Holding metal fitting, 21 ... Housing side plate.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Shinichi Ishida 2-6-1, Marunouchi, Chiyoda-ku, Tokyo Furukawa Electric Co., Ltd. (72) Kikuo Hara 2-6-1, Marunouchi, Chiyoda-ku, Tokyo No. Furukawa Electric Co., Ltd. (72) Inventor Tatsuo Horii 2-6-1, Marunouchi, Chiyoda-ku, Tokyo Within Furukawa Electric Co., Ltd.

Claims (1)

[Claims] 1. A heat source is provided at one end of a heat pipe to serve as a heat input portion, and a heat radiator is attached to the other end of the heat pipe to serve as a heat radiation portion. The portion sandwiched between the heat radiating portion is bent to form a bent portion, the heat radiating portion of the heat pipe has a hardness necessary to attach the heat radiating fin, and the bent portion of the heat pipe is compared to the heat radiating portion. A heat pipe cooler characterized by being soft.