Conventional housings for elements such as cable television transmission circuitry are designed to handle temperatures up to 50 degrees Celsius. Most conventional housings have only external fins located on an exterior portion of a cast aluminum housing structure to dissipate heat generated by the electronic components housed therein. This has proven effective to cool components directly mounted on the inside surface of the housing, wherein the heat they generate radiates through the cast aluminum and out to the external environment. However, not all parts can be mounted directly to the housing, such as AC bypass coils. These parts dissipate their heat to the surrounding air inside the housing. Thus, the temperature of the air becomes substantially higher than the outside air temperature. High temperatures inside the housing can damage heat sensitive components such as fiber optic components.
Thus, a problem exists in that heat builds up in the sealed, moisture proof, airtight housings, which may be underground, mounted above ground on walls, poles or pedestals, or strand-mounted, suspended from an overhead cable. Accordingly, there is a need to develop a more efficient cooling method, to conduct heat from inside the housing to the outside environment, where it can be dissipated. Fans have been implemented inside the housing to cool the environment. However, fans take up space in the housing and require power. Further, fans generate heat which also must be accounted for inside the housing.
U.S. Pat. No. 5,267,122 to Glover et al. discloses a technique for conducting heat to the outside environment. In particular, Glover et al. provides internal fins each protruding from the housing into its hollow interior, adjacent to printed circuit cards to promote heat dissipation from the cards via the internal fins to the exterior walls of the housing for cooling by external cooling fins exposed to the outside environment. Adjacent fins are dedicated to a particular circuit board inserted therebetween and consequently only assist in cooling the dedicated circuit board therebetween. The heat generated by circuit boards and electronic components can vary significantly from component to component. Thus, it is inefficient to dedicate only two internal fins to cooling a particular circuit board.
USPTO Backgrounds
USPTO Backgrounds