GB2406441A

GB2406441A - Heat sink with arcuate fins

Info

Publication number: GB2406441A
Application number: GB0322364A
Authority: GB
Inventors: Richard Ma
Original assignee: Giga Byte Technology Co Ltd
Current assignee: Giga Byte Technology Co Ltd
Priority date: 2003-09-24
Filing date: 2003-09-24
Publication date: 2005-03-30
Anticipated expiration: 2023-09-24
Also published as: GB0322364D0; GB2406441B; DE20315170U1

Abstract

A heat sink has two arrays of arcuate fins 300, 400 of opposite curvature. Shorter fins 310,410,500 may also be provided.

Description

240644 1

HEATSINK

The invention relates to a heatsink for heat-generating devices. In particular, it relates to a heatsink arranged to be used with a side blowing fan.

Heat dissipation is a major consideration in electronic device design. An electronic device is comprised of a lot of electronic elements. Taking the computer as an example, there are many electronic elements on the motherboard that can generate a tremendous amount of heat during operations.

Such elements include the central processing unit (CPU), the communications lo chips, the graphics chip, and the dual in-line memory modules (DlMM's). These electronic elements have become much faster than before. For example, the clock frequency of the CPU is now commonly over IGHz, with a heat-dissipating power of SOW. If the heat cannot be immediately removed, such electronic elements may be overheated to affect their stability and reliability and to shorten their lifetime. Therefore, heat dissipation becomes a serious problem as electronic device frequencies increase.

Currently, electronic device heat dissipation is achieved by heat conduction, convection or radiation to release the generated heat to the environment. A primary means is to use the combination of a heatsink and a fan.

The heatsink is made of metal. It has a heat-conductive base whose bottom is directly installed on the electronic device that generates heat. The heat conductive base is formed with several heat-dissipating plates to help dissipating heat. The heat produced by the heat-generating electronic device is transferred via the heat-conductive base to the heatdissipating plates. The fan generates airflow through the plates for heat exchange. The heated air is then expelled, taking away the heat from the heat-dissipating plate module and lowering the temperature of the electronic device.

Generally speaking, the heat-dissipation efficiency of the heatsink is usually determined by its material and structure. The early heatsinks were often made of aluminum because of its small thermal resistance, light weight and low cost. However, as electronic device clock frequencies continuously increase, the heat-dissipation efficiency has to be increased too. Therefore, manufacturers began to use copper as the material for heatsinks. The thermal conduction coefficient of copper is about 1.8 times that of aluminum, while the density of copper is about 3 times that of aluminum. In otherwords, for heatsinks of the same volume and area, the one made of copper is 3 times heavier than that made of aluminum. Therefore, although a heatsink made of copper has a better thermal conduction coefficient than that made of aluminum; the former is much heavier than the latter. It is therefore necessary to take both the weight and the thermal conduction coefficient factors into account.

lo Existing heatsinks on the market are all made of materials with similar compositions. The heat-dissipation efficiencies are also very close. Therefore, increasing heat dissipation by improving the structure has become the main research goal of the manufacturers. For example, the heat-dissipating plates are usually installed vertically on the base of a heatsink. One of the features of such a vertical heatsink is that the flat plates provide straight airflow channels.

However, the drawbacks of this structure are that the heat-conductive area is too small, that the heat transfer time is too short, and that the parallel airflow cannot provide ideal heat convection after leaving the plates. Even though a layered structure is provided, there is still scope for improvement.

no Thus in the known heatsink designs having a vertical heat-dissipating fin the heat conduction area is small, the heat transfer time is short, and the linear airflow channels cannot provide ideal heat convection effects.

An object of the present invention is to alleviate at least some of the above problems.

In view of the foregoing, in one embodiment a heatsink includes: a heat conductive base installed on a heat-generating component of an electronic device; several first heat-dissipating fins vertically installed at intervals on one half side of the heat-conductive base; several second heat-dissipating fins vertically installed at intervals on the other half side of the heat-conductive base.

so Each of the first heat-dissipating fins has a curved surface and these fins are parallel to one another. The space between adjacent first heatdissipating fins forms a first airflow space for air to pass through. Each of the second heat dissipating fins has a curved surface and these fins also are parallel to one another. However, the curvatures of the second heat-dissipating fins are opposite to those of the first heatdissipating fins. The space between adjacent second heat-dissipating fins forms a second airflow space for air to pass through.

The curved first heat-dissipating fins and second heat-dissipating fins increase the heat-conductive area and increase the heat transfer period is elongated, and the curved airflow paths provide ideal heat convection effects.

The invention will become more fully understood from the non-limiting in detailed description of a preferred embodiment given hereinbelow by way of illustration only with reference to Figure 1 and 2, wherein: Fig. 1 is a three-dimensional view of a preferred embodiment of the invention; and Fig. 2 is a schematic top view of Fig. 1.

Is With reference to Figs. 1 and 2, the heatsink 100 according to a preferred embodiment of the invention can be applied to heat-generating devices such as the CPU, the communication chips, the graphics chip, and the DlMM's protecting such devices from damage due to overheating. The heatsink 100 is made of metal with a high thermal conduction coefficient (e.g. aluminum or copper). It consists of a heat-conductive base 200, several first heat-dissipating fins 300, several second heat-dissipating fins 400, and two third heat-dissipating fins 500.

The heat-conductive base 200 is a shaped block that is complementary to the shape of the heat-generating device. Its bottom is attached to the heat generating device (not shown) for direct contact. Generally speaking a heat dissipating gel is applied between the heat-conductive base 200 and the heat generating device. This increases the thermal conductance of the system.

The first heat-dissipating fins 300 are vertically installed on the front half side of the heat-conductive base 200 (referring to Fig. 1). Each of the first heat dissipating fins 300 has an arc shape. They are installed by gluing or welding.

so They can also be formed by cutting, pressing or extrusion. All the first heat dissipating fins 300 are parallel and equal in length. The centers of the curved surfaces are aligned. The space between adjacent first heat-dissipating fins 300 is a first airflow space 320, forming a curved airflow path. Moreover, the outermost first heat-dissipating fin 310 is shorter for fitting the rectangular shape of the heat-conductive base 200.

The second heat-dissipating fins 400 are also installed vertically on the rear half side of the heat-conductive base 200 (see Fig. 1). Each of the second heat-dissipating fins 400 has an arc shape. They are installed by gluing or welding. They can also be formed by cutting, pressing or extrusion. Although the centers of the second heat dissipating fins 400 are also aligned similarly to to those of the first heat-dissipating fins 300, they are on opposite sides. All the second heat-dissipating fins 400 are parallel and equal in length. The space between adjacent first heatdissipating fins 400 is a first airflow space 420, forming a curved airflow path. Similarly, the outermost first heat-dissipating fin 410 is also shorter for fitting the rectangular shape of the heat- conductive base 200.

The third heat-dissipating fins 500 are also installed vertically on the heat conductive base 200. They are on the outer sides of the neighbouring area between the first heat-dissipating fins 300 and the second heatdissipating fins 400. The purpose of having these two third heat-dissipating fins 500 is to fully utilize the space, increasing the heat-dissipation area. They are straight without bending to either side. Optionally the two third heat-dissipating fins can be omitted.

After installing the disclosed heat-dissipating fin module 100 on a heat generating device, a fan is provided on one side (not shown) to produce airflow.

The airflow paths are shown in Fig. 2. Since both the first heatdissipating fins 300 and the second heat-dissipating fins 400 have curved surfaces, there is a larger heat-dissipation area and the curved airflow paths are longer and increase the heat transfer period. As the airflow paths on both sides do not cross or overlap, a better heat convection effect is achieved.

so Certain variations would be apparent to those skilled in the art, which variations are considered within the scope of the claimed invention. s

Claims

CLAIMS: 1. A heat-dissipating fin module comprising: a heat-conductive

base, which in use is installed on a heat-generating component of an electronic device; a plurality of first heat-dissipating fins, which are vertically installed at intervals on one half side of the heat-conductive base, each of the first heat- dissipating fins having an arc surface parallel to one another, and the space between adjacent first heat-dissipating fins forming a first airflow space for lo providing a curved airflow path; and a plurality of second heat-dissipating fins, which are vertically installed at intervals on the other half side of the heat-conductive base, each of the second heat-dissipating fins having an arc surface parallel to one another but having curvature centers opposite to those of the first heat-dissipating fins, and the space between adjacent second heat-dissipating fins forming a second airflow space for providing a curved airflow path that does not cross the airflow path of the first airflow space.
2. A heatsink according to claim 1, wherein the first heat-dissipating fins and the second heat-dissipating fins are equal in length.
3. A heatsink according to claim 1 or claim 2, wherein the curvature centers of the first heat-dissipating fins and the second heatdissipating fins are mutually aligned.
4. A heatsink according to claim 1, wherein the outermost first heat dissipating fin and second heat-dissipating fin are shorter than the other first and second fins.
5. A heatsink according to any preceding claim, wherein the first heatdissipating fins and the second heat-dissipating fins are installed on the heat- conductive base by gluing or welding.

s
6. A heatsink according to any preceding claim, wherein the first heatdissipating fins and the second heat-dissipating fins are formed on the heat- conductive base by cutting, pressing or extrusion.
7. A heatsink according to any preceding claim, wherein the first heat o dissipating fins and the second heat-dissipating fins have trimmed sides.
8. A heatsink according to any preceding claim, further comprising at least one third heat-dissipating fin installed vertically in the outer region between the first heat-dissipating fins and the second heatdissipating fins on the heat s conductive base.
9. A heatsink according to claim 8, wherein the third heat-dissipating fin is straight.
10. A heatsink according to claim 8 or claim 9, wherein the third heatdissipating fin is installed by a method selected from gluing and welding.
11. A heatsink according to any of claims 8 to 10, wherein the third heatdissipating fin is formed by cutting and pressing.
12. A heatsink comprising: a heat-conductive base, which in use is installed on a heat-generating component of an electronic device; a plurality of first heat-dissipating fins, which are vertically installed at intervals on one half side of the heat-conductive base, each of the first heat- dissipating fins having an arc surface parallel to one another, and the space between adjacent first heat-dissipating fins forming a first airflow space for providing a curved airflow path; a plurality of second heat-dissipating fins, which are vertically installed at intervals on the other half side of the heat-conductive base, each of the second heat- dissipating fins having an arc surface parallel to one another but having curvature centers opposite to those of the first heat-dissipating fins, and the space between adjacent second heat-dissipating fins forming a second airflow space for providing a curved airflow path that does not cross the airflow path of the first airflow space; and lo at least one third heat-dissipating fin, which is vertically installed on the heat- conductive base in an outer region between the first heat-dissipating fins and the second heat-dissipating fins.
13. A heatsink according to claim 12, wherein the first heat-dissipating fins and the second heat-dissipating fins are equal in length.
14. A heatsink according to claim 12 or claim 13, wherein the curvature centers of the first heat-dissipating fins and the second heatdissipating fins are mutually aligned.
15. A heatsink according to claim 12, wherein the outermost first heat dissipating fin and second heat-dissipating fin are shorter than the other fins.
16. A heatsink according to any of claims 12 to 15, wherein the third heat dissipating fin is straight.
17. A heatsink according to any of claims 12 to 16, wherein the first heat- dissipating fins, the second heat-dissipating fins, and the third heat- dissipating fins are installed on the heat-conductive base by gluing or welding.
18. A heatsink according to any of claims 12 to 17, wherein the first heat- dissipating fins, the second heat-dissipating fins, and the third heat- dissipating fins are formed on the heat-conductive base by cutting and pressing.
19. A heatsink having a first array of curved heat-dissipating fins which are spaced apart to define curved airflow paths between them and a second array of curved heat-dissipating fins which are spaced apart to define further curved airflow paths between them, the arrays being disposed with their convex fin surfaces facing so that the airflow paths of the respective arrays initially converge lo and then diverge.
20. A heatsink substantially as described hereinabove with reference to Figures 1 and 2 of the accompanying drawings.