The present invention relates to a hybrid cooling apparatus and method for cooling electronic devices and more particularly to a hybrid cooling apparatus and method for cooling integrated circuit chips and the like.
High performance microprocessors and integrated circuit chips generate considerable heat in small spaces. Further, as the processing speeds are increased so is the amount of heat generated. Accordingly, there is a continuing need for improved thermal cooling to maintain acceptable operating perimeters.
Recently, a number of computer processor manufactures have employed heat sinks such as fined metallic pieces put on the chips to dissipate heat by conduction and fans to increase the heat loss by convection. For example, U.S. patent of Krein, U.S. Pat. No. 5,734,552 discloses an airfoil deflector for cooling components. As disclosed therein, a deflector shaped in cross-section like an airfoil directs a stream of fluid such as air from a fan toward a heat-generating chip to improve cooling of the chip. The foil is inverted as compared with an airplane wing to produce an inverse lift at reduced temperatures to cool a heat sink thermally. The airflow effect also moves air away from the component at increased velocity to cool it more rapidly. In confined areas multiple deflectors may be arranged in the manner of sails of a boat for augmenting cooling.
A further approach for cooling an electronic device is disclosed in a U.S. Pat. No. 6,050,326 of Evans et al. The Evans et al. patent discloses a method and apparatus for cooling one or more electronic devices. The apparatus utilizes a moving heat sink, a portion of which is in contact with the device to be cooled. The moving heat sink may be in the form of a rotating disk, moving belt or strip and may be made from metal or plastic.
A more recent approach for cooling electronic devices is disclosed in a U.S. Pat. No. 6,371,200 of Eaton which discloses a perforated heat sink having high heat dissipation. As described in the patent, the heat sink includes a substrate with a multitude of holes and a thermal conductive pathway to conduct heat from a heat source to the substrate. The surface area of the holes is equal to or greater than the surface of the substrate without the holes.
Notwithstanding the above, it is presently believed that there is a need for an improved cooling system and method for cooling heat generating electronic devices such as integrated circuit chips. It is also believed that the present need and a potential commercial market will increase as the speed of such devices increases. Further advantages contemplated by the present invention are a relatively compact size, a need for a reasonable amount of power, relatively silent operation and a competitive cost.
In essence, the present invention contemplates a cooling system for cooling an integrated circuit chip or logic chip hereinafter referred to as an integrated circuit chip. The system includes a heat generating integrated circuit chip having a heat emanating surface and conductive means such as an endless metal belt in sliding contact with the heat emanating surface. The cooling system also includes convection means such as a fan or jet for simultaneously moving a cooling fluid such as air across the conductive means for removing dissipated heat from the chip by convection.
In a first embodiment of the invention, the convection means includes means such as a fan for passing an airflow over the convection means and an airfoil having a leading edge and a trailing edge, a first surface remote from the heat emanating surface and a second convex surface opposite from the heat emanating surface but separated therefrom by a portion of the heat transfer element and a predetermined space to thereby define a convergent divergent duct shape to thereby increase the flow speed and alter the pressure distribution on the conduction means.
The present invention also contemplates a method for cooling a heat generating electronic device which includes the step of providing a heat generating electronic device having a heat emanating surface and removing heat from the heat emanating surface by convection as for example by providing a heat absorbing material having a surface area larger than the heat emanating surface in sliding contact with the heat emanating surface and moving the heat absorbing material across the heat emanating surface. The method also includes the step of simultaneously removing dissipated heat from the electronic device by convection, as for example by moving a cooling fluid such as air across the heat absorbing material and/or chip. In this embodiment of the invention the speed of the cooling medium is increased as it flows across the heat absorbing material and the pressure distribution across the heat absorbing material and/or chip is altered.
The invention will now be described in connection with the following figures wherein like reference numerals have been used to identify like parts.
a is a schematic illustration of a first embodiment of the invention;
b is a schematic illustration of a further embodiment of the invention;
a is a schematic illustration of yet another embodiment of the invention;
b is a schematic illustration of an additional embodiment of the invention; and
A hybrid cooling system or apparatus for cooling a heat generating electronic device in accordance with a first embodiment of the invention is illustrated in
An endless belt 26 of a heat absorbing and dissipating material such as a metal as for example stainless steel, aluminum, copper, etc. is disposed in contact with the heat emanating surface 22. As illustrated a C-shaped channel 27 which may be made of metal such as stainless steel or other suitable material guides an endless belt 66 which may be in sliding contact with the channel 27 or in contact with the surface 22. However, it should be recognized that the invention contemplates an endless belt 26 which is in direct contact with the heat emanating surface 22 or an indirect contact therewith by contacting the channel 27.
The endless belt 26 passes around a plurality of rollers 28, 29, 30 and 31 and is moved across the heat emanating surface by means of a gear 32 or other conventional means. The moving belt 26 is in sliding contact with the surface of the chip 20 or with a C-shaped channel 27 and acts as a moving heat sink as different portions of the belt 26 come in contact with the surface 22 of the chip or with the C-shaped channel 27.
A fan 34 or jet 34′ simultaneously directs a flow of air or other cooling fluid across the surface of the belt 26 preferably in the area immediately adjacent to the C-shaped channel 27.
A negatively cambered airfoil 36 is disposed above the C-shaped channel 27 and chip 20. This airfoil 36 forms a convergent-divergent duct shape with the C-channel and belt 26. In a preferred embodiment of the invention, the airfoil 36 or wing includes a moving skin or belt 37 which moves in the same direction as the moving belt 26. The advantage of the airfoil/wing is to improve the cooling process by increasing the airflow speed and altering the pressure distribution across the moving belt or chip. This reduces the temperature according to the gas law as manifested by the equation pv=nRT where p is the absolute pressure, v is the volume, n is the number of moles, R is the universal gas constant and T is the absolute temperature. Further, the moving skin or belt 37 increases the speed of adjacent airflow leading to a decrease in the temperature and more rapid removal of the heated air above the chip. In other words, it increases the rate of cooling according to Bernoulli's equation (P+½ρV2=constant where P is the pressure, p is the fluid density and V is the fluid velocity.
As illustrated in
It is also contemplated that the wing like airfoil can be replaced with other geometric shapes that will produce the convergent-divergent duct effect.
A further embodiment of the invention as shown in
A still further embodiment of the invention is illustrated in
Further, the airfoil 36 may include interior cooling fins 50 as shown in
A method for cooling an integrated circuit chip as illustrated in
In one embodiment of the invention the endless belt is moved through a coolant in step 71.
While the invention has been described in connection with its preferred embodiments, it should be recognized that changes and modifications may be made therein without departing from the scope of the appended claims.
Number | Name | Date | Kind |
---|---|---|---|
2834582 | Kablitz | May 1958 | A |
3158198 | Hunter, Jr. | Nov 1964 | A |
3956673 | Seid | May 1976 | A |
4144932 | Voigt | Mar 1979 | A |
4235283 | Gupta | Nov 1980 | A |
4541004 | Moore | Sep 1985 | A |
4603243 | Septfons et al. | Jul 1986 | A |
4616693 | Dietzsch et al. | Oct 1986 | A |
4880049 | Jaeger | Nov 1989 | A |
4986346 | Blackmon et al. | Jan 1991 | A |
5021924 | Kieda et al. | Jun 1991 | A |
5062471 | Jaeger | Nov 1991 | A |
5092241 | Feser et al. | Mar 1992 | A |
5119142 | Swapceinski et al. | Jun 1992 | A |
5221181 | Ferleger et al. | Jun 1993 | A |
5288203 | Thomas | Feb 1994 | A |
5292230 | Brown | Mar 1994 | A |
5335143 | Maling, Jr. et al. | Aug 1994 | A |
5424914 | Smith et al. | Jun 1995 | A |
5504924 | Ohashi et al. | Apr 1996 | A |
5562089 | Astle, Jr | Oct 1996 | A |
5597035 | Smith et al. | Jan 1997 | A |
5609202 | Anderson et al. | Mar 1997 | A |
5615085 | Wakabayashi et al. | Mar 1997 | A |
5734552 | Krein | Mar 1998 | A |
5828549 | Gandre et al. | Oct 1998 | A |
6000997 | Kao et al. | Dec 1999 | A |
6050326 | Evans et al. | Apr 2000 | A |
6168379 | Bauer | Jan 2001 | B1 |
6175495 | Batchelder | Jan 2001 | B1 |
6333852 | Lin | Dec 2001 | B1 |
6371200 | Eaton | Apr 2002 | B1 |
6373700 | Wang | Apr 2002 | B1 |
6467274 | Barclay et al. | Oct 2002 | B2 |
6567640 | Ishikawa et al. | May 2003 | B2 |
Number | Date | Country | |
---|---|---|---|
20050199383 A1 | Sep 2005 | US |