Extended surface area heat sink

Details Extended surface area heat sink Extended surface area heat sink

2000-07-25

2001-11-06

Picard, Leo P. (Department: 2835)

Electricity: electrical systems and devices

Housing or mounting assemblies with diverse electrical...

For electronic systems and devices

C361S700000, C361S709000, C361S710000, C361S719000, C361S720000, C257S706000, C257S714000, C257S715000, C257S717000, C165S080300, C165S080400, C165S185000, C174S015200, C174S016300

Reexamination Certificate

active

06313994

ABSTRACT:

BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention generally relates to heat sinks for computer systems, and more particularly to a heat sink for a high energy consumption device, such as a central processing unit, which may be placed in close proximity to low power consumption components, such as memory chips.
2. Description of the Related Art
Computer systems such as workstations, personal computers, and portable computers may include components housed within an enclosure. Some components, such as central processing unit (devices) and memory chips, typically mount on circuit boards within the enclosure. Other components, such as circuit boards and disk drives, typically mount to a chassis of the computer system.
Only a limited amount of space exists within a computer enclosure. Computer systems may be designed to make the best use of the available space. Computer components need to be in close proximity to each other so that the best performance from the computer components may be obtained. However, having computer components in close proximity to each other may be problematic due to geometry and heat generation factors within the computer enclosure.
A computer component may function properly only when an operating temperature of the component is at or below a maximum operating temperature. In some instances, a package surface area of a component is too small to permit sufficient heat transfer from the package to keep the component at or below maximum operating temperatures using natural convection. Such a component requires additional cooling. If the temperature of a computer component exceeds the maximum operating temperature of the component, or if the temperature within the computer enclosure exceeds a maximum operating temperature, a reduction of computer performance may occur. Eventually, the components of the computer system may be permanently damaged or destroyed if the computer components or the computer system are operated at too hot a temperature.
Some computer components may be high power consumption devices. High power consumption devices typically generate large amounts of heat during use. Generally, high power consumption devices require cooling to function properly. The cooling of a high power consumption device may be accomplished by attaching a heat sink to the high power consumption device. The high power consumption device transfers heat to the heat sink, and the heat sink transfers the heat to the surroundings. One type of heat sink provides a thermal connection between a heat transfer surface of the high power consumption device and a convection cooled surface area of the heat sink. A cooling fan, or cooling fans, within the computer enclosure may provide forced convection to transfer heat from the heat sink to the surroundings if natural convection within the computer enclosure does not provide enough heat transfer to the surroundings. It is desirable to provide a heat sink for a high power consumption device that has a large heat transfer surface area. The heat sink should allow the device to operate at as low a temperature as possible.
One type of heat sink for a high power consumption device includes a base having a plurality of fins extending from an upper surface of the base. The base has a lower surface that generally corresponds to the principal heat transfer surface of the high power consumption device. The upper surface of the base typically has the same shape as the lower surface of the base. The fins provide extended heat transfer surface area for the heat sink.
Another type of heat sink for a high power consumption device is shown in U.S. Pat. No. 5,412,535, issued to Chao et al, and is incorporated by reference as if fully set forth herein. The heat sink comprises a base with a vertically mounted heat pipe connected to the base. The lower surface of the base thermally contacts the heat transfer surface of the high power consumption device. Horizontal fins extend from the heat pipe to increase the heat transfer surface area of the heat sink.
Some computer components, such as a collection of static random access memory (SRAM) units, may be low power consumption components. Low power consumption components may require heat sinks to keep the components functioning properly. A heat sink for a low power consumption component may be required if the component generates excessive heat during use, or if the component is placed near a high power consumption device. Individual heat sinks may be provided for individual low power consumption components, or one heat sink may be used to cool several low power consumption components.
SUMMARY OF THE INVENTION
A finned heat sink for a high power consumption device includes extended heat transfer surface area that overhangs portions of a circuit board adjacent to the high power consumption device. Low power consumption components may be mounted in close proximity to the high power consumption device. A portion of the heat sink may extend over the low power consumption components. Sufficient room may exist between overhanging portions of the heat sink and the low power consumption components to allow an optional heat sink or a plurality of optional heat sinks to be attached to the low power consumption components.
The heat sink for the high power consumption device may require the addition of a high thermal conductivity material to a portion of the heat sink that contacts a heat transfer surface of the high power consumption device. The high thermal conductivity material may help to spread heat transferred from the high power consumption device throughout the heat sink. The high thermal conductivity material may absorb high heat flux generated by the high power consumption device. The high thermal conductivity material may spread the heat flux throughout the finned heat sink to promote efficient heat transfer from fins of the heat sink to the surroundings. The high thermal conductivity material may be a metal, such as copper or a copper alloy, and/or the high thermal conductivity material may include a heat pipe or heat pipes. A heat pipe may be a vapor chamber plate type of heat pipe. A heat pipe may be mounted or interleaved in a surface of the extended area heat sink. A heat pipe or a surface of the extended area heat sink immediately adjacent to the heat pipe may be placed in thermal contact with the high power consumption device.
An extended area heat sink for a high power consumption device may allow the components of a computer system to be placed close together within a computer enclosure. Placing the components of a computer system close together may allow the computer enclosure to be small. Close placement of the computer components and devices may allow for improved performance of a computer system. Because the heat sink for the high power consumption device has extra heat transfer surface area, cooling fans within the computer system may be operated at lower speeds while still providing sufficient system cooling. Operating system fans at low speeds may reduce acoustic noise generated by the computer system. Operating the system fans at low speeds may also extend the life of the fans.
An advantage of an extended area heat sink is that the heat sink may allow the development of faster and more efficient electronic devices. Components of a system may be located adjacent to a high power consumption device that generates a large amount of heat. The heat generated by the high power consumption device may be dissipated by the extended area heat sink. The close proximity of components to the high power device may allow for more efficient, faster, and smaller electronic systems.
Another advantage of an extended area heat sink is that the heat sink may allow for a reduction in noise generated by a system. The extended area heat sink may allow system fans to run at low speeds so that the overall noise generated by a system is reduced. Running a fan at a low fan speed may help to extend the life of the fan. A low fan speed may also help to ensure that the system meets environmental regulator

Affiliated with

Also associated with

Rating

Extended surface area heat sink does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Extended surface area heat sink, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Extended surface area heat sink will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2601388