Membrane keyboard apparatus having common apertured electrode, aperture inserted electrodes and conductive bubble contactors

Abstract

Membrane keyboard apparatus is disclosed as including an insulator having a conductive sheet thereon providing a plurality of first electrode members and a plurality of second electrode members to form an array of individual switching units. A membrane member is disposed in a spaced relation above and adjacent to the level of the top surfaces of the pluralities of first and second electrode members. The membrane member is formed of a flexible, plastic, insulative sheet member, and includes: an array of indicia corresponding to the array of individual switching units formed on the first, bottom surface of the sheet member; a background color layer formed on the bottom surface of the sheet member and over the array of indicia; a very thin, conductive layer formed on the background color layer and applied to form patterned areas for providing a conductive path between the first and second electrode members of the individual switching units selected; and height differential members formed in the membrane member. The height differential members formed in the membrane member have a first, actuated position where the conductive layer provides a conductive path between the associated first and second electrode members of the actuated individual switching unit and a second, nonactuated, normal position where the conductive layer is electrically spaced from at least the second electrode members to electrically insulate the first electrode members and the second electrode members.

Dependencies are inferred from the claim text.