US20080029249A1

US20080029249A1 - Supporting column having porous structure

Info

Publication number: US20080029249A1
Application number: US11/497,723
Authority: US
Inventors: Wei-Che Hsiao
Original assignee: Inventec Corp
Current assignee: Inventec Corp
Priority date: 2006-08-01
Filing date: 2006-08-01
Publication date: 2008-02-07

Abstract

A supporting column having a porous structure is installed in a chamber filled with working fluid. The chamber includes an evaporation side for evaporating the working fluid to the gaseous phase, and a condensation side opposite the evaporation side for condensing the gaseous phase to the liquid phase. The supporting column includes a supporting body and the porous structure formed on the supporting body. Two ends of the supporting body are connected to the evaporation side and the condensation side respectively. The porous structure is supported by the supporting body and configured to convey the working fluid. Accordingly, heat dissipation is achieved by phase cycling of the working fluid.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention
The present invention relates to a supporting column, and more particularly, to a supporting column having a porous structure and installed in a chamber filled with working fluid, thus conveying the working fluid with a view to achieving heat dissipation.
2. Description of Related Art
In 1963, G. M. Grover invented heat pipe technology. A heat pipe is a heat transmitting device based on the principles of heat transfer as well as a property of cooling media—rapid heat transfer. A heat pipe is typically fully-sealed and vacuum-maintained so as to facilitate rapid heat transfer through evaporation and condensation. It has other advantages, namely adjustable heat transfer areas on both the cold and hot interfaces, long-distance heat transfer, and controllable temperature. A heat exchanger composed of heat pipes has advantages, such as efficient heat transfer, compact structure, and low flow impedance. Accordingly, heat pipes have an effective thermal conductivity much greater than that of any known metal.
In recent years, CPU operating voltage increases with the ever-increasing CPU performance, which causes a typical CPU to generate an ever-increasing amount of unwanted heat. Removal of the unwanted heat necessitates a relatively high cooling fan rotation speed. But indiscriminately increasing the cooling fan rotation speed for the sake of efficient heat dissipation inevitably overloads a power supply and produces noise.
For the aforesaid reasons, heat pipe technology is applied to a CPU cooling device. As shown in FIG. 1, a cooler 1 comprises a chamber 10, a condensation side 11, and an evaporation side 12. Disposed on the condensation side 11 is a cooling fin 13. In contact with the evaporation side 12 is a heat generating element 14 such as a CPU. The chamber 10 is filled with working fluid of a high expansion coefficient. A plurality of columns 15 are disposed between two opposing walls of the chamber 10. With powder sintering, the columns 15 are made porous so as to soak up the working fluid by capillarity.
The heat generating element 14 in operation generates heat. The heat generated is then absorbed by an evaporation side-neighboring portion of each of the columns 15, and thus the working fluid held by the evaporation side-neighboring portion of each of the columns 15 is heated up and evaporated to the gaseous phase. As a result, the working fluid held in a condensation side-neighboring portion of each of the columns 15 is conveyed in the direction of the evaporation side 12, whereas the working fluid in its gaseous phase moves in the opposite direction until it reaches the condensation side 11 and condenses to its liquid phase. Then, the working fluid in its liquid phase is soaked up by the columns 15 and conveyed in the direction of the evaporation side 12. Phase cycling as described above enables heat dissipation to occur.
Although heat pipe technology enhances the efficiency of heat dissipation performed by the cooler 1, it has its own drawbacks.
After functioning, that is, drawing in and delivering the working fluid, for a long period of time, the columns 15 is susceptible to aging—peeling off and resultant structural damage.
Formed by powder sintering, the columns 15 are likely to be fragile. Once the chamber 10 is deformed as a result of an external force exerted on the cooler 1, the columns 15 will be readily damaged.
Once the cooler 1 expands upon heating, the dimensions of the chamber 10 will increase, elongating the columns 15. Given time, the columns 15 are compromised in terms of structure and then capillarity.
Accordingly, there is an urgent need to solve the aforesaid problems.

SUMMARY OF THE INVENTION

In light of the above-mentioned drawbacks of the prior art, it is a primary objective of the present invention to provide a supporting column having a porous structure with a view to reinforcing the supporting column.
Another objective of the present invention is to provide a supporting column having a porous structure with a view to providing capillarity for achieving heat dissipation.
To achieve the above-mentioned and other objectives, the present invention discloses a supporting column having a porous structure. The supporting column is installed in a chamber filled with working fluid. The chamber comprises an evaporation side for evaporating the working fluid to the gaseous phase, and a condensation side opposite the evaporation side for condensing the gaseous phase to the liquid phase. The supporting column comprises a supporting body and the porous structure. Two ends of the supporting body are respectively connected with the evaporation side and the condensation side. The porous structure is formed on the supporting body and thereby supported by the supporting body. The porous structure is configured to convey the working fluid such that heat dissipation occurs in the chamber by the phase cycling of the working fluid.
The chamber is disposed in a cooler. The chamber comprises the condensation side and the evaporation side. The condensation side is equipped with a cooling fin. The evaporation side is in contact with a heat generating element. The working fluid, with which the chamber is filled, has a low boiling point and thereby evaporates readily. After absorbing heat from the evaporation side, the working fluid evaporates into gas, and then the gas flows in the direction of the condensation side.
The supporting body is one of a solid column and a hollow column. The porous structure comes in a variety of ways. The porous structure can be fabricated by powder sintering and formed on the supporting body. Alternatively, the supporting body can be provided with a plurality of grooves, enclosed by metal wire netting, or surrounded by a plurality of circumferentially disposed metal wires which are secured in position on the supporting body by a fastening element running spirally.
Compared to the prior art, the present invention discloses a supporting column having both a supporting body and a porous structure, wherein the supporting body not only supports the porous structure and thereby protects the porous structure from damage done by an external force, but also supports the chamber and thereby prevents the chamber from being deformed by an external force.
In short, the present invention discloses a supporting column having both a supporting body and a porous structure, wherein porous structure is structurally reinforced and thereby is less susceptible to structural damage but is more conducive to heat dissipation by a cooler.

BRIEF DESCRIPTION OF DRAWINGS

The invention can be more fully understood by reading the following detailed description of the preferred embodiments, with reference made to the accompanying drawings, wherein:

FIG. 1 (PRIOR ART) shows a conventional cooler based on heat pipe technology;

FIG. 2A is a schematic diagram showing application of a supporting column to a cooler in accordance with the present invention;

FIG. 2B is an elevational cross-sectional view of the first embodiment of a supporting column of the present invention;

FIG. 3 is a top plan view of the second embodiment of a supporting column of the present invention;

FIG. 4 is an elevational view of the third embodiment of a supporting column of the present invention;

FIGS. 5A and 5B are a top plan view and an elevational view of the fourth embodiment of a supporting column of the present invention; and

FIG. 6 is a top plan view of the fifth embodiment of a supporting column of the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The following specific embodiments are provided in conjunction with the appended drawings to illustrate the disclosure of the present invention, these and other technical features and effects are apparent to those ordinarily skilled in the art after reading the disclosure of this specification.

The First Embodiment

Referring to FIG. 2A, a cooler 2 comprises a chamber 22 including a condensation side 220 and an evaporation side 221. Disposed on the condensation side 220 is a cooling fin 23. In contact with the evaporation side 221 is a heat generating element 24 like a CPU. The chamber 22 is filled with working fluid of a low boiling point. The heat generating element 24 in operation generates heat, and thus the working fluid is heated up and evaporated into gas. Heat dissipation is carried out by means of the cooling fin 23 such that the gas is condensed into liquid. Accordingly, heat dissipation is achieved by phase cycling of the working fluid.
The present invention discloses a supporting column 25 having both a supporting body 250 and a porous structure 251. The supporting column 25 is disposed inside the chamber 22. Two ends of the supporting column 25 are connected to the evaporation side 221 and the condensation side 220. The porous structure 251 is formed on and thereby supported by the supporting body 250. Porosity allows the porous structure 251 to exhibit capillarity, and in consequence the porous structure 251 is capable of conveying the working fluid. As shown in FIG. 2B, the porous structure 251 of the supporting column 25 of the present invention is fabricated by powder sintering and formed on the supporting body 250, and the supporting body 250 can be either a solid column for supporting the porous structure 251 or a hollow column (not shown).

The Second Embodiment

FIG. 3 is a top plan view of the second embodiment of a supporting column of the present invention. This embodiment differs from the first embodiment in two ways. In this embodiment, a plurality of grooves 250 a are formed on the supporting body 250, and cross sections of the grooves 250 a are triangular in shape or in any processing friendly shape, for example, rectangular.

The Third Embodiment

FIG. 4 is an elevational view of the third embodiment of a supporting column of the present invention. This embodiment differs from the preceding embodiment in the way that the porous structure 251 comprises metal wire netting 252 so as to provide capillarity by tiny meshes.

The Fourth Embodiment

FIGS. 5A and 5B are a top plan view and an elevational view of the fourth embodiment of a supporting column of the present invention. This embodiment differs from the preceding embodiment in the way as follows: the porous structure 251 comprises a plurality of metal wires 253 disposed around the supporting body 250 and secured in position on the supporting body 250 by a fastening element 254 running spirally, such that narrow gaps between the metal wires 253 provide the porosity required for the aforesaid capillarity.

The Fifth Embodiment

FIG. 6 is a top plan view of the fifth embodiment of a supporting column of the present invention. In this embodiment, the porous structure results from a combination of the second and the fourth embodiments, that is, the plurality of grooves 250 a configured to hold the metal wires 253 are formed on the supporting body 250, and the metal wires 253 are secured in position in the grooves 250 a by the fastening element 254 running spirally.
Unlike prior art disclosing a capillary column which is fragile and vulnerable, the present invention discloses a supporting column having both a supporting body and a porous structure and, as a result, not only does the supporting body support the porous structure and thereby protect the porous structure from damage done by an external force, but the supporting body also supports the chamber and thereby prevents the chamber from being deformed by an external force.
In the present invention, a porous structure of any kind is always disposed on the supporting body rather than connected to the condensation side and the evaporation side; hence, the porous structure will not be damaged, even if the chamber expands or deforms upon thermal expansion of the cooler.
In the present invention, with structural reinforcement from a supporting body, not only can a supporting column work in conjunction with a variety of porous structures, but it is feasible to combine different porous structures so as to enhance the capillarity.
In short, the present invention discloses a supporting column having both a supporting body and a porous structure. The porous structure is reinforced and thereby less susceptible to damage. Different porous structures may be combined so as to enhance the capillarity. Accordingly, heat dissipation by a cooler is optimized.
The foregoing specific embodiments are only illustrative of the features and functions of the present invention but are not intended to restrict the scope of the present invention. It is apparent to those skilled in the art that all modifications and variations made in the foregoing embodiments according to the spirit and principle in the disclosure of the present invention should fall within the scope of the appended claims.

Claims

1. A supporting column having a porous structure and disposed in a chamber filled with working fluid, the chamber having an evaporation side and a condensation side opposite the evaporation side, the evaporating side allowing the working fluid to evaporate into gas, the condensation side allowing the gas to condense into liquid, the supporting column comprising:

a supporting body having two ends connected to the evaporation side and the condensation side respectively; and

a porous structure disposed on and thereby supported by the supporting body, such that the porous structure conveys the working fluid and allows heat dissipation to occur in the chamber by phase cycling of the working fluid.

2. The supporting column of claim 1, wherein the supporting body is one of a solid column and a hollow column.

3. The supporting column of claim 1, wherein the porous structure is fabricated by powder sintering.

4. The supporting column of claim 1, wherein the supporting body further comprises a plurality of grooves.

5. The supporting column of claim 4, wherein at least one of the grooves has a cross section selected from the group consisting of a triangle and a rectangle.

6. The supporting column of claim 1, wherein the porous structure comprises metal wire netting.

7. The supporting column of claim 1, wherein the porous structure comprises a plurality of metal wires disposed around the supporting body and secured in position on the supporting body by a fastening element running spirally.

8. The supporting column of claim 7, wherein the supporting body comprises a plurality of circumferentially disposed grooves for holding the metal wires respectively.

9. The supporting column of claim 8, wherein at least one of the grooves has a cross section selected from the group consisting of a triangle and a rectangle.

10. The supporting column of claim 1, wherein the chamber is disposed in a cooler and provided with the condensation side having a cooling fin and the evaporation side in contact with a heat generating element.