Membrane keyboard apparatus
US3995126A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 3, 1975 |
| Grant date | Nov 30, 1976 |
| Priority date | — |
| Expiry date | Apr 3, 1995 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H2229/028
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Membrane keyboard apparatus is disclosed including an insulator having a conductive sheet thereon providing a plurality of first electrode members in the form of an array of apertures, and a plurality of second electrode members located concentrically within and spaced from the periphery of the apertures of the first electrodes to form an array of individual switching units. The height of the conductive sheet is greater than the height of the second electrode members whereby the level of the top surfaces of the plurality of first electrode members is vertically spaced above the level of the top surfaces of the second electrode members. A flexible, conductive 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. An identification member having an array of indicia corresponding to the array of individual switching units is disposed in a spaced relation above and adjacent to the flexible conductor. A threshold member is included in the form of an array of elastic bubble members corresponding to the array of individual switching units and including air escape means for the bubble members to …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.