Browse Prior Art Database

Composite Cover

IP.com Disclosure Number: IPCOM000083412D
Original Publication Date: 1975-May-01
Included in the Prior Art Database: 2005-Mar-01
Document File: 2 page(s) / 51K

Publishing Venue

IBM

Related People

Lockhart, MA: AUTHOR [+2]

Abstract

Panels and doors, especially those utilized for computers, must be rigid since the doors must be in electrical contact with the machine frame when the door is closed for electromagnetic shielding purposes. Using the known door and panel manufacturing techniques, doors of sufficient rigidity tend to be excessively heavy and expensive to manufacture.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 64% of the total text.

Page 1 of 2

Composite Cover

Panels and doors, especially those utilized for computers, must be rigid since the doors must be in electrical contact with the machine frame when the door is closed for electromagnetic shielding purposes. Using the known door and panel manufacturing techniques, doors of sufficient rigidity tend to be excessively heavy and expensive to manufacture.

This improved composite cover or panel consists of an outside decorative prefinished metal, such as vinyl clad thin aluminum or steel. The inner surface can be preferably of terne which is lead-tin coated steel. Between these two surfaces, there is a core of rigid polyurethane foam which is "foamed in place". This type of construction requires no painting or finishing. It provides a light weight, low cost, precisely flat and highly rigid panel.

Flatness and rigidity is a must to properly seal the electrical conductive rubber gasket to meet electromagnetic compatibility (EMC) requirements, as well as acoustical and dust seal requirements. The rigid core foam is flame retardant. The cover can be further strengthened by an increase in the density of the foam. Curved surfaces can be fabricated just as easily as flat panels, unlike honeycomb and other types of construction.

The foam is introduced into a completely closed volume except for the filling holes. The front and back surfaces or sheets are fastened together by a lock seam shown in the figure. This contains the foam and at the same time vents air fro...