Exhaust system for electronic equipment enclosure

#1. Field of the Invention

#The present invention relates to an exhaust system for electrical equipment enclosures and, more particularly, to a top cover for electronic equipment enclosures which provide better thermal insulation and noise abatement as well as other benefits.

#2. Description of the Related Art

#FIG. 1 is a front perspective view of an electronic equipment enclosure.

#FIG. 2 is a diagrammatic side elevational view of the enclosure of FIG. 1.

#FIG. 3 is a top isometric view of an enclosure cover.

#While the present invention is open to various modifications and alternative constructions, the preferred embodiment shown in the drawings will be described herein in detail. It is understood, however, that there is no intention to limit the invention to the particular form disclosed. On the contrary, the intention is to cover all modifications, equivalent structures and methods, and alternative constructions falling within the spirit and scope of the invention as expressed in the appended claims.

#An electronic equipment enclosure or cabinet typically is a free standing box-like structure located out-of-doors where it is bolted to a concrete slab and where it is exposed to the sun, rain, wind and other environmental and climatic elements. These enclosures or cabinets are designed to house a variety of electronic equipment, for example, digital loop carriers, fiber optic transport systems, radio equipment for wireless applications, and remote power systems as well as telephone equipment. Because the enclosure is situated out-of-doors, there is a need to be concerned about such matters as high temperatures and direct exposure to the sun on the one hand and hurricane weather on the other as well as impacts from such items as bullets and pellets. Referring now to FIGS. 1 and 2, there is illustrated such an enclosure 10 having a front wall 12 with two access doors 14 and 16, a pair of sidewalls, such as the wall 18, and a rear wall 20 also having two access doors (not shown). In addition, the enclosure includes a top cover 22. The enclosure includes a sealed upper chamber 24 for the electronic equipment and a back-up battery lower chamber 26 which is open to ambient air. The back-up battery 28 is useful should there be an electrical outage. The electronic equipment, fiber optics, radio equipment or the like 30, 31 is located in the sealed upper chamber 24 attached to racks that also provide a frame for the enclosure. The enclosure is also provided with a heat exchanger 32 because the electronic equipment generates heat. Heat build up may also be caused by solar impingement. As shown in FIG. 2, the heat exchanger draws in outside air represented by the arrows 34 through louvers 35 into the bottom chamber 26 and into the heat exchanger 32. This intake of outside air is accomplished by a powerful centrifugal fan 36 at the top of the heat exchanger. The air is then passed through an exhaust duct 38 and exhausted to the ambient air through a screen 40 as depicted by the arrow 42. This movement of air, in addition to supplying cool air to the heat exchanger, also ventilates the lower chamber 26 to prevent any undesirable gas or heat build-up from the batteries 28.

#The heat exchanger 32 is known as a dual air, vertical flow device. Heated air from the sealed upper chamber 24 represented by the phantom curves 44, 45 travels in a circular pattern where it is cooled in the heat exchanger. This heated air from the equipment in the sealed upper chamber is sucked through openings 46, 48 in the upper portion of the heat exchanger and then is drawn downwardly by fans 50, 51 at the bottom of the heat exchanger. In the process, heat is transferred from the hot, downwardly moving equipment air to the cool upwardly moving ambient air. The cooled equipment air is exhausted through vents 52, 54 near the bottom of the heat exchanger 32. As can be appreciated, the equipment air from the sealed chamber 24 never mixes with the cooling ambient air.