Digit display apparatus

Claim 1

IN COMBINATION WITH A DIGIT MODULE OF THE TYPE HAVING SEVEN PRINCIPAL CHARACTER SEGMENTS INDEPENDENTLY ILLUMINATED BY LAMPS FOR SELECTIVELY PRODUCING A VISUAL INDICATION OF A DESIRED DIGIT, CIRCUIT MEANS FOR CONTROLLING THE SELECTION OF THE LAMPS TO BE ILLUMINATED COMPRISING ACTUATING MEANS INDIVIDUAL TO EACH DIGIT TO BE INDICATED, FIRST SWITCHING MEANS ASSOCIATED WITH EACH ACTUATING MEANS AND SECOND SWITCHING MEANS ASSOCIATED WITH EACH ACTUATING MEANS FOR DIGITS WHERE ONE OR MORE OF THE LAMPS USED TO PRODUCE THE DIGITAL INDICATION OF THE DIGIT 8 ARE NOT ENERGIZED, A COMMON CONTROL CONDUCTOR CONNECTED TO ONE TERMINAL OF THE DIGIT 8 IS PRODUCED AND TO SAID FIRST SWITCHING MEANS, A POWER SUPPLY FOR SAID LAMPS HAVING ONE TERMINAL CONNECTED TO EACH OF SAID FIRST SWITCHING MEANS, CIRCUIT MEANS CONNECTING A SECOND TERMINAL OF EACH OF THE LAMPS NOT ENERGIZED WHEN THE DIGITAL INDICATION OF A DIGIT HAVING A SMALL NUMBER OF SEGMENTS ILLUMINATED IS PRODUCED TO A SECOND TERMINAL OF SAID POWER SUPPLY THROUGH NORMALLY CLOSED CONTACTS OF THE SECOND SWITCH CONTACTS OF THE ACTUATING MEANS ASSOCIATED WITH SAID LAST MENTIONED DIGIT, SAID NORMALLY CLOSED CONTACTS BEING OPENED WHEN SAID LAST MENTIONED DIGIT IS SELECTED, MEANS CONNECTING THE LAMPS ENERGIZED TO PRODUCE A DIGITAL INDICATION OF SAID LAST MENTIONED DIGIT TO SAID ONE TERMINAL OF SAID POWER SUPPLY, AND SAID OTHER SECOND SWITCHING MEANS SELECTIVELY DISCONNECTING THE ENERGIZING CIRCUIT FOR THE LAMPS NOT ENERGIZED WHEN DIGITAL INDICATIONS OF OTHER DIGITS ARE PRODUCED.