| 摘要 |
<p>FLAT KEYBOARD ASSEMBLY A flat keyboard assembly including a printed circuit board having conductors on one side thereof. Resilient dome switch elements are supported on the one side of the board in spacedapart relationship in peripheral contact with certain conductors and adapted to make center contact with other conductors upon the application of force thereon. A sheet of relatively thin insulating material covers the one side of the board, the dome elements and the conductors thereon. A switch-actuating member formed of relatively thin, flexible insulating material is in facing relationship with the insulator sheet and has switchactuating protrusions thereon respectively in alignment with the switch elements and extending toward and contacting the insulator sheet. The actuating member also has isolator protrusions thereon intermediate the switch-actuating protrusions and respectively in alignment with the spaces between the dome elements and extending toward the insulator sheet. A flat keyboard member also formed of relatively thin, flexible material has one side in facing relationship with the actuator member and has keyboard indicia on its other side respectively in alignment with the switch-actuating protrusions and the switch elements. The board, insulator sheet, actuating member and keyboard member are held in assembled relation with the insulator sheet and actuator member sandwiched between the board and the keyboard member so that deflection of the keyboard member in the region of a particular indicia in response to force manually exerted thereon causes the respective switchactuating protrusion to actuate the respective switch element through the insulator sheet, force exerted on the keyboard member at a particular indicia being isolated by the isolator protrusions from the dome elements aligned with other indicia.</p> |
