Low configuration keyboard

Claim 1

A keyboard comprising individual switches activated by depression of a keybutton at each of said switches each switch including a solid base attached to said keyboard having a vertical post and a recess circumferentially around said post, a first flexible membrane mounted on said base having an opening surrounding said post and an extension .located over said recess, said extension supporting a first electrical conductor of said switch on the side away from said recess, a spacer membrane mounted on said first flexible membrane having an opening surrounding said post and said extension of said first flexible membrane, a second flexible membrane mounted on said spacer membrane having an opening surrounding said post and an extension located over said extension of said first flexible membrane and supporting a second electrical conductor of said switch facing said first electrical conductor of said switch, a resilient membrane having a dome configuration with a hole in the center mounted on said second flexible membrane, and a keybutton having a post and at least one rib, said post of said keybutton movably meshing with said vertical post of said solid base to support said keybutton laterally while permitting longitudinal movement of said keybutton and said rib being positioned over said recess, said dome holding said keybutton away from said base in the absence of keying pressure on said keybutton toward said base and said keybutton being moveable toward said base in response to said keying pressure, said rib extending through said dome for contacting and deflecting said extension of said second flexible member into said extension of said first flexible membrane to bring said first and said second electrical conductors into contact to activate said switch.