Patent · US Expired

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

US3988551A · kind A · utility

23Cited by
9References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 3, 1975
Grant dateOct 26, 1976
Priority date
Expiry dateApr 3, 1995

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01H2229/05
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

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…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.