Patent ID: 7449646

Claim:
A pneumatically actuated switching device comprising: a dome with a convex actuating wall terminating at an elliptical edge and including spaced apart support columns protruding from a concave inner face surface of said convex actuating wall; a base including receptacles for anchoring said support columns to a floor bounded by an elliptical perimeter symmetrical about each of a major axis and a minor axis and joined to an endless upstanding sidewall having a projected edge that varies continuously in height about one of said major axis and said minor axis, said projected edge having one of a channel and a locking lip and the other of said channel and said locking lip being formed on said elliptical edge for interlocking engagement in an air tight fashion; and an electrically conductive switch coupled by a duct for responding to a volume of pressurized air within said dome and said base by deflection of said convex actuating wall.