Keyboard switch assembly having interchangeable cover plate, indicating layer and actuator switch assembly in any operative combination

A keyboard comprising:

• a. support means;
• b. a switch matrix secured to said support means having a flexible surface for generating a plurality of electrical signals in response to the movement of an actuating member to a position engaging and depressing a portion of said flexible surface;
• and
• c. a keyboard jacket assembly positioned adjacent said switch matrix, said jacket assembly having a lower surface composed of depending projections engaging the flexible surface of said switch matrix and a flexible upper surface, said projections being responsive to deflection of portions of said flexible upper surface for effecting depression of said flexible surface to generate signals, said jacket assembly further including cover means having a configuration which extends over a predetermined portion of said flexible upper surface for disabling the covered portions of the flexible upper surface from being deflected.

A manually actuable keyboard assembly comprising:

• a. a switch matrix comprising a substrate having a first conductor mounted in the top surface thereof;
• b. an insulating member positioned on said substrate and having openings therein;
• c. a deformable membrane positioned on said insulating member and adapted for movement through said opening, said membrane having second conductors mounted adjacent the opening of said insulating member, and said substrate, insulating member and membrane being secured together in a watertight relationship;
• d. a jacket assembly positioned adjacent said membrane and comprising a second substrate having projections depending therefrom in registration with respective openings in said insulating member;
• e. a transparent deformable membrane having key portions formed therein, said transparent membrane and said second substrate positioned in spaced apart relationship forming a recessed area;
• f. a sheet removably positioned within said recessed area and having indicia thereon aligned with said key portions;
• g. and a cover member having a configuration which extends over a predetermined portion of said transparent deformable membrane to expose a predetermined number of said key portions while overlying the remaining key portions whereby only those key portions exposed by said cover member are available for operation.