JPH03133165A - Heat pipe system heat dissipating unit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a heat pipe type heat dissipation unit that uses a heat pipe to dissipate heat generated from a heat generating element installed in an electronic device such as a computer, and in particular, The present invention relates to a heat pipe type heat dissipation unit in which the heat pipe can function effectively even when installation space is limited.

[Conventional technology]

Computers are classified into personal computers (PCs) depending on their purpose, size, processing speed, etc.

They are broadly divided into office computers (office computers), large computers, and ultra-high-speed/ultra-large computers (supercomputers).

These computers had different cooling methods due to differences in the amount of heat generated by the heat generating elements installed.

In the case of a personal computer, the amount of heat generated by the C-MO3 element is large, and each element generates about 2 to 3 W of heat. For this reason,
Cooling is achieved by forced air cooling, which uses a fan to blow air over the surface of the heating element.

In the case of an office computer, the LSI generates a large amount of heat, and each element generates about 2 to 3 W of heat. Compared to personal computers, office computers need to have faster processing speeds, so they have a larger number of heat-generating elements, and the spacing between the elements is smaller. Since this alone does not provide sufficient cooling, heat dissipation fins are attached to the top of the heating element, and a fan is used to force cooling by blowing air through it.

In the case of large-sized computers, the processing speed becomes even faster, so the amount of heat generated by the LSI increases to about 3 to 7 W per element. This problem has been solved by increasing the size of the fins attached to the heating elements and increasing the speed of the air passing through them.

Recently, the amount of heat generated has been increasing, so some devices have cooling coils attached to the fins to dissipate heat.

In the case of supercomputers, the heat generated by the LSI increases to 8 to 30 W per element, and forced air cooling is no longer sufficient to cool the LSI, so liquid cooling or boiling cooling such as freon is used.

[Problem to be solved by the invention]

However, the cooling of each of the computers described above has the following problems.

Computers have a problem with forced cooling, which causes a lot of fan noise. Currently, only 3 to 4 of the heat generating elements used in computers require forced cooling, so if the heat generated by these elements could be diffused, natural air cooling would also be possible. However, there was no compact heat dissipation unit with sufficient heat dissipation performance.

Office computers have a major problem with noise caused by air blowing, and countermeasures have been proposed such as reducing the wind speed to reduce noise, but to do so, a high-performance heat dissipation unit is required.

Large computers generate more heat as their processing speeds increase, so some computers are no longer able to be cooled by air cooling. Water-cooled heat radiators have complicated systems and reduce reliability as a whole, so there is a desire for a heat radiator unit that can air-cool the heat generating element until the amount of heat generated is about 20 W or less.

Supercomputers have no choice but to use liquid cooling, so
The challenge is to simplify the system.

Generally, in these computer systems, the mounting space for a heatsink is an extremely important issue.

Heat dissipation units using heat pipes have been developed to make heat dissipators more compact and highly efficient, but even in such heat dissipation units, the size of the heat pipe must be kept to a minimum.

FIG. 2 is a diagram for explaining problems with the heat pipe type heat dissipation unit.

As a heat dissipation unit using a heat pipe, the following configuration can be considered.

A heat receiving part (evaporating side) 6a of a heat pipe bent into an L shape is attached to the upper surface of the block 5, and a fin 7 is attached to a heat dissipating part (condensing side) 6b protruding from the block 5.

In this way, by joining the block 5 to the upper surface of the heating element 8, heat from the heating element 8 can be transferred to the block 5-
The heat can be transmitted to the heat receiving part 6a of the heat piper through the heat piper, and the heat can be radiated from the heat radiation part 6b of the heat piper via the fins 7.

However, when the mounting density of the heating elements 8 on the board increases,
The heat pipes that protrude from the block 5 tend to stand in a forest, making it impossible to bend the heat pipes parallel to the substrate surface. At this time, the fins 7 are attached to the heat radiation part 6b of the heat pipe, so
It becomes more difficult to bend.

Furthermore, if the space above the substrate is limited, the length of the heat dissipation section 6b of each heat pipe can only be very limited.

Furthermore, as a means of attaching the heat piper to the block 5, it seems effective to bend the heat receiving part 6a 90 degrees and paste or embed it, but for example, when the outer diameter of the heat piper A is about 3 mm Due to processing, it is not possible to reduce the radius of curvature R of the bent portion below a certain level, and the limit is at most 10 mm (two-dot chain line in Figure 2).

On the other hand, since the area of the block 5 is also limited, if the radius of curvature R of the straight pipe portion of the heat pipe pro A attached to the block 5 is 10 mm, the radius of curvature will be almost equal to zero.

Therefore, it has been found that if the space for installing the heat dissipation unit is limited, it is practically difficult to bend the heat pipe and install it on the block 5 as described above.

Leave the heat pipe as a straight tube and connect it to block 5.
It is also possible to increase the heat receiving area by vertically inserting the heat pipe into the block 5 and increasing the thickness of the inner body of the block 5. They will compete for the height of the limited space,
It is difficult for both the heat receiving section 6a and the heat dissipating section 6b to have sufficient heat transfer surfaces.

An object of the present invention is to solve the above-mentioned problems, and to provide a heat pipe type heat dissipation unit that is compact and has high heat dissipation efficiency, in which both the heat receiving part and the heat dissipation part of the heat pipe have a sufficient heat transfer surface. The goal is to provide the following.

[Means to solve the problem]

In order to solve the above problems, a heat pipe type heat dissipation unit according to the present invention has a first surface to which a heat generating element is attached and a second surface to which a heat pipe is attached, and a gap between the first and second surfaces. A block in which a heat radiating fin part is formed on the outer surface of the thick part between the blocks, and a block in which a heat receiving part is inserted in the thickness direction from the second surface of the block, and a heat radiating part protrudes from the second surface. Alternatively, it is composed of a plurality of straight heat pipes and heat radiating fins provided in the heat radiating portion of the heat pipe.

At this time, the block has a cylindrical shape, the bottom surface of the cylinder is used as the element mounting surface, and the heat receiving portion of the heat pipe is arranged so as to penetrate from the top surface of the cylinder toward the bottom surface or to the vicinity of the bottom surface. An insertion hole into which the cylinder is inserted may be provided, and a fin portion may be formed by machining the side surface of the cylinder into an uneven shape.

Further, the block has an outer diameter of 20 to 40 mm.

The heat pipe may have a height of 5 to 20 mm, and a heat dissipation portion of the heat pipe may have a length of 10 to 60 mm.

Note that metal materials such as aluminum and copper can be suitably used as materials for the block, the heat pipe, and the fin.

[Effect]

According to the above configuration, the heat pipe can receive heat from the thick portion of the block, and can also radiate heat from the fin portion of the block in addition to the heat radiated from the fins attached to the heat pipe.

〔Example〕

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

FIG. 1 is a diagram showing an embodiment of a heat pipe type heat dissipation unit according to the present invention.

In Fig. 1, 1 is a block, 2 is a heat pipe, and 3 is a block.
is a fin, and 4 is a heating element.

In this embodiment, the block 1 is made of aluminum into a cylindrical shape with a diameter of 28 mm and a height of 10 mm, and the bottom surface of the cylindrical column serves as an element mounting surface 1a on which the heating element 4 is attached. This block 1 is provided with an insertion hole 1b extending from the upper base to the lower base of the cylinder, and the heat receiving portion 2a of the heat pipe 2 can be inserted into the insertion hole 1b.

Furthermore, a fin portion 1c is formed in the block 1 by machining the side surface of a cylinder into an uneven shape.

The heat pipe 2 is a straight pipe-shaped container made of copper with an outer diameter of about 3 mm and filled with a working fluid such as pure water, and the heat receiving part 2a is inserted into the insertion hole 1b of the block 1. In this embodiment, two heat pipes 2 are attached.

The heat dissipation part 2b of the heat pipe 2 protrudes from the block 1, and is provided with heat dissipation fins 3 made of a large number of aluminum plates arranged at predetermined intervals.

Next, the heat dissipation unit of this embodiment will be explained in comparison with the heat dissipation unit shown in FIG.

Now, as shown in Figure 1, the space for installing the heat dissipation unit is height A = 30 mm and width B =
Assume that the space is limited to a 30 mm opening.

At this time, with a heat dissipation unit that is attached by bending the heat pipes as shown in 2nd rM, it is not possible to install a sufficient number of heat pipes, and it is difficult to reduce the radius of curvature R during bending. (3mmφ
As mentioned above, the radius of curvature R is approximately 10 mm for a copper pipe.

On the other hand, in the heat dissipation unit of this embodiment, since the heat pipe 2 has a straight tube shape and is inserted into the block 1, only the thickness C=10 mm of the block 1 functions reliably as the heat receiving part 2a.

Furthermore, the length of the heat dissipation part 2b of the heat pipe 2 is 20 mm.
Therefore, when considering the heat transfer process of the entire system, the heat transfer surface of the heat radiation section 2b is reduced. Therefore, in this embodiment, the fin portion IC is provided on the side surface of the block I,
This is to compensate for the decrease in the heat dissipation portion 2b of the heat pipe 2.

In this case, in the block 1, heat from inside is radiated from the fins 3 via the heat pipe 2, and heat is radiated from the outside of the block 1 by the fin portion 1c.

Therefore, even when compared with the heat dissipation unit of the form shown in FIG. 2, it has a sufficient heat dissipation surface. In other words, by allowing the block 1 to have both heat receiving and heat dissipating functions by itself, heat can be effectively dissipated using a heat pipe in an extremely limited space.

The present invention is not limited to the embodiments described above, and various modifications can be made within the scope of the present invention.

The shape of the block is not limited to a cylinder, but may be a rectangular parallelepiped, and the dimensions of each part are not limited to those described above. In order to insert the heat pipes, the insertion holes provided in the block may be made to pass through the block.The number of heat pipes inserted into the block can be selected as appropriate depending on the installation space and the amount of heat dissipation. It may be a book or three or more books.

〔Effect of the invention〕

As explained in detail above, according to the present invention, even when installed in a limited space, both the heat receiving part and the heat radiating part of the heat pipe have sufficient heat transfer surfaces, and the heat pipe can be compact and efficiently radiate heat. A pipe-type heat dissipation unit has been realized.

At this time, there is no need to bend the heat pipe, which simplifies manufacturing and reduces costs.

Further, with the embodiment of the present invention, even when it is desired to attach a plurality of heat pipes, the attachment can be easily performed.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of a heat pipe type heat dissipation unit according to the present invention. FIG. 2 is a diagram for explaining problems with the heat pipe type heat dissipation unit.

Claims (3)

[Claims] (1) It has a first surface to which the heating element is attached and a second surface to which the heat pipe is attached, and a heat dissipation fin portion is formed on the outer surface of the thick part between the first and second surfaces. a heat receiving part is inserted in the thickness direction from the second surface of the block, one or more straight tube-shaped heat pipes with a heat radiating part protruding from the second surface, and the heat pipe of the heat pipe. A heat pipe type heat dissipation unit consisting of heat dissipation fins provided in the heat dissipation section. (2) The block has a cylindrical shape, the bottom surface of the cylinder is the element mounting surface, and the heat receiving portion of the heat pipe is arranged so as to penetrate from the top surface of the cylinder toward the bottom surface or to the vicinity of the bottom surface. 2. The heat pipe type heat dissipation unit according to claim 1, wherein the heat pipe type heat dissipation unit is provided with an insertion hole into which the heat pipe is inserted, and the fin portion is formed by machining the side surface of the cylinder into an uneven shape. (3) The block has an outer diameter of 20 to 40 mm and a height of 5 to 20 mm, and the heat pipe has a heat dissipation portion having a length of 10 to 60 mm.
) Heat pipe type heat dissipation unit.