STRUCTURAL FRAMES FOR ELECTRICALLY SHIELDED ENCLOSURES

摘要

A single piece, seamless structural frame comprising oppositely disposed end members connected by side walls. Each end member is comprised of a honeycomb array of apertures. An electrically conductive coating extends over the interior and exterior surfaces of the side walls and end members including the aperture walls. The frame can be constructed from a plastics based material using a low pressure structural foam molding process and the electrically conductive coating may be a two-layer electroless plated coating of copper and nickel. Alternatively, a plastics based material incorporating a conductive filler may be used with a limited width band of electrically conductive material around a peripheral surface area of the frame. The frame has particular utility as a card cage enclosure for printed circuit cards and associated power supply units in a computer system. The seamless frame enhances attenuation shielding against EMI/RFI radiation from the components within the container while allowing coolant air flow to move through registers defined by the end wall apertures.