Braille display switching matrix and circuit utilizing the same

Claim 2

In an improved electronic instrument of the type comprising a digital logic circuit having a decimal digital data source, the improvement of which comprises a touch controlled switching matrix comprising an electrically conductive substrate, at least one series of raised electrically conductive terminals disposed on said substrate and divided into coded groups, each of said groups being representative of a different digit in the decimal system from 0 through 9, and means for insulating said terminals from said substrate in such a manner as to permit any selected one of said groups to be shorted with a finger to said substrate, each of said groups being electrically connected to said data source, means for generating an audible signal responsively connected to said substrate for generating said signal when one of said groups bearing a signal from said data source is shorted with a finger to said substrate.

Claim 3

An electronic circuit adapted for operative association with a digital electronic instrument of the type comprising logic circuitry adapted to generate a timed sequence of digital signals, each of said signals being representative of decimal digit of a multi-digit number and containing components coded in segmented logic, said electronic circuit comprising means for sampling a portion of each of said digital signals and for converting each of said portions from said segmented logic into an equivalent decimal coded signal, a switching matrix comprising an electrically conductive substrate being electrically divided into a plurality of segments, each of said segments being representative of different digit positions of said multi-digit number, an array of raised electrical terminals disposed of said substrate and being divided into a plurality of sets, each of said sets representing a different one of said digit positions and containing coded groupings of said terminals representing the digits 0 through 9, each of said sets being disposed on a different one of said segments, means for insulating said terminals from said substrate in such a manner as to permit any selected one of said groupings to be shorted by a fingertip to said substrate, each of said groupings representing the same decimal digit being electrically connected to a corresponding digital signal output source of said sampling and converting means, digital selection logic means comprising a plurality of input terminals, each of said input terminals being responsively connected to a different one of said segments, a plurality of timing signal terminals, each of said timing signal terminals being connectible to a source of timing signals in said instrument representative of a different one of said digit positions, means for comparing the simultaneous occurrence of said signals of said input and timing signal terminals for generating a signal when one of said groupings is shorted to said substrate which is energized by a signal from said sampling and converting means, said energized grouping being contained in one of said sets representative of one of said digital signals of said ordered sequence, and audio transducer logic circuitry adapted to generate an audible sound responsively connected to said comparing means.

Claim 4

An electronic circuit adapted for operative association with a digital electronic instrument of the type comprising logic circuitry adapted to generate a timed sequence of digital signals, each of said signals being representative of decimal digit of a multi-digit number and containing components coded in segmented logic, said electronic circuit comprising means for sampling a portion of each of said digital signals and for converting each of said portions from said segmented logic into an equivalent decimal coded signal, a switching matrix comprising an electrically conductive substrate being electrically divided into a plurality of segments, each of said segments being representative of different digit positions of said multi-digit number, an array of raised electrical terminals disposed of said substrate and being divided into a plurality of sets, each of said sets representing a different one of said digit positions and containing coded groupings of said terminals representing the digits 0 through 9, each of said sets being disposed on a different one of said segments, means for insulating said terminals from said substrate in such a manner as to permit any selected one of said groupings to be shorted by a fingertip to said substrate, each of said groupings representing the same decimal digit being electrically connected to a corresponding digital signal output source of said sampling and converting means, digital selection logic means comprising a plurality of input terminals, each of said input terminals being responsively connected to a different one of said segments, a plurality of timing signal terminals, each of said timing signal terminals being connectible to a source of timing signals in said instrument representative of a different one of said digit positions, means for comparing the simultaneous occurrence of said signals of said input and timing signal terminals for generating a signal when one of said groupings is shorted to said substrate which is energized by a signal from said sampling and converting means, said energized grouping being contained in one of said sets representative of one of said digital signals of said ordered sequence, and audio transducer logic circuitry adapted to generate an audible sound responsively connected to said comparing means.