Zenith Electronics Corporation

S&c Electric Company

Bernard M Wiltgen

Arthur J Lostumo

A thick film resistive network circuit board to be potted is given a surface coat of epoxy on one side which does not cover the solder pads or electrical connections, thereby allowing further working of the board. The epoxy coat is applied in such a fashion that it does not obscure or cover a second side of the board having a potentiometer network thereon in the preferred embodiment. The epoxy coat provides a good surface for adhesion of a potting epoxy as well as good adhesion to the board, and thereby prevents breakdown of the dielectric properties of the high voltage circuitry into which the board is fitted.

High voltage resistive network circuit board with good potting adhesion

An epoxy resin composition, especially useful as an encapsulant and exhibiting a low dissipation factor, is prepared from a first component comprising an epoxy of a polyglycidal ether of a polyhydroxyl phenol and filler, and a second component comprising a cycloaliphatic acid anhydride curing agent, filler and catalyst. Each component is mixed separately under high shear, and the filler for each component comprises at least about 50 percent by weight. The two components are admixed, applied as an encapsulant, and cured at an elevated temperature.

Epoxy compositions, and method of making same

An arc quenching composition suitable for deionizing and extinguishing a high voltage electrical arc comprising an effective proportion of hexamethylenetetramine. Depending on the application in which the arc extinguishing composition is employed, the hexamethylenetetramine may be utilized alone, admixed with a suitable binder, or used to impregnate another material.

Arc extinguishing material

An arc quenching composition suitable for deionizing and extinguishing a high voltage electrical arc comprising an effective proportion of dicyandiamide. Depending on the application in which the arc extinguishing composition is employed, the dicyandiamide may be utilized alone, admixed with a suitable binder, or used to impregnate another material.

Growing community of inventors

Villa Park, IL, United States of America

Bernard M Wiltgen