Abstract: A tactile or snap action membrane keyboard is presented wherein the tactile or snap action key elements are protrusions in a membrane sheet, each protrusion having a flat elliptical top surface or plateau with a plurality of inclined ramps from the base sheet to the plateau.

Abstract: An electrical switch assembly of the type comprising a pair of printed circuits separated by an apertured spacer wherein passages are provided to vent gas from the region of each individual switch and the edge of the assembly.

Abstract: A membrane keyboard and method of formation thereof is presented in which the spacing and insulation between fixed and movable circuit layers is achieved by a dielectric material screened or otherwise applied to one of the circuit layers in a predetermined pattern. The dielectric pattern has openings to permit electrical contact between layers, and the dielectric pattern includes a discontinuous pattern of dielectric material on at least one of the contact elements to maintain separation between the contacts while still permitting actuation of the device.

Abstract: An activation device is presented for a tactile keyboard of the type having a molded monolithic plastic layer of tactile elements. The actuator is a thermocompressively molded monolithic plastic layer which incorporates a matrix of geometrically designed strikers, the actuator layer being interposed between the keys and the molded monolithic plastic layer of tactile elements in a keyboard assembly.