The present invention relates generally to entertainment systems and more particularly to thermal management systems for single or multiplayer disk systems used as stand-alone units or in multimedia systems.
Radios have long been used to provide entertainment and information for the listener. More recently, other types of entertainment systems have either been incorporated into radios or function as stand-alone units. These include among others cassette players, compact disk (xe2x80x9cCDxe2x80x9d) units, digital audio tapes (xe2x80x9cDATxe2x80x9d) and digital video disk (xe2x80x9cDVDxe2x80x9d) units.
One problem with disk players, whether used in a stand-alone unit or within the disk portion of multimedia systems, is heat buildup. Heat buildup is a result of electronic components with higher power dissipation coupled with packaging constraints. Studies have shown that the heat emitted from the electronics and motor within a multimedia radio causes hot media and disk shutdown concerns. Similar concerns are found in stand-alone disk units.
Many techniques are currently used to try to dissipate the heat. For example, heat sinks are typically mounted to all radios and serve to remove heat. Heat sinks work well in single media radios, but do not dissipate enough heat from the disk components to be effective in multimedia systems or stand-alone disk units.
Also, electric fans added to the disk portion of the multimedia radio have been evaluated. The fans are used to try to dissipate the heat buildup from the surface of the disk. This technique is unworkable due to space constraints within the disk portion which limit the amount of available locations for mounting the fans. Other locations that are typically available to mount the electric fans do not provide ideal heat dissipation. Thus, to add an electric fan to dissipate the heat would require a large-scale design change, a costly and time consuming endeavor.
Further, thermoelectric devices and other heat management systems were evaluated in the disk portion of the multimedia radios. With these electrically driven devices, heat is pulled away from the heat source, in this case the disk portion. These devices were found to be ineffective for this application.
It is thus an object of the present invention to dissipate heat buildup in close proximity to the rotational disk component contained in a stand-alone disk unit or within the multimedia radio.
The above object is accomplished by applying the Von Karman Viscous xe2x80x9cPumpxe2x80x9d Principle to optimize airflow within the disk region to ventilate heated air away from the disk component and its related electronics. In application, this is accomplished by adding a series of venting holes to the housing that surrounds the disk portion at a position directly above or below the center of a disk. These venting holes induce ambient airflow to the center portion of the disk when the disk is spinning. As the disk rotates, the hot air is expelled outwardly away from the center of the disk. Another series of holes are added to the side of the housing to remove the heated air from the disk. In one preferred embodiment of the present invention, the surface of a CD placed into a multimedia radio having the hole design was approximately 10-15% (on a Centigrade Scale) cooler than the surface of a CD placed in a multimedia radio without the additional hole design.
It is contemplated that the present invention is ideally suited for combination radio/CD players used on automobiles and for combination radio/DVD players used on automobiles or for stand alone single or multiplayer CD and DVD players.
Other objects and advantages of the present invention will become apparent upon considering the following detailed description and appended claims, and upon reference to the accompanying drawings.