Device and method for controlling exposure in a photographic color printer

Claim 1

IN A PHOTOGRAPHIC COLOR PRINTER, AN EXPOSURE LAMP FOR SUPPLYING WHILE LIGHT THROUGH A NEGATIVE ONTO PHOTOGRAPHIC MULTICOLOR SENSITIVE MATERIAL, A SHUTTER NORMALLY BIASED TO CLOSED POSITION SO AS TO BLOCK THE PASSAGE OF LIGHT FROM SAID LAMP TO SAID MATERIAL, A SOLENOID FOR ACTUATING SAID SHUTTER INTO OPEN POSITION TO SIMULTANEOUSLY EXPOSE SAID MATERIAL TO THE THREE PRIMARY COLORS RED, GREEN AND BLUE CONTAINED IN THE WHITE LIGHT SUPPLIED BY SAID LAMP, CONTROL MEANS FOR ENERGIZING SAID SHUTTER-ACTUATING SOLENOID TO INITIATE A WHITE LIGHT EXPOSURE PERIOD WHEN SAID CONTROL MEANS IS CONNECTED TO A SOURCE OF POWER MEANS FOR SAMPLING THE LIGHT IMPINGING UPON THE MATERIAL FOR FURNISHING RESPECTIVE ELECTRICAL SIGNALS PROPORTIONAL TO THE RED LIGHT, THE SAMPLED GREEN LIGHT, AND THE SAMPLED BLUE LIGHT, THE TIMING CIRCUIT CONTROLLED BY THE ELECTRICAL ENERGY REPRESENTING THE SAMPLED RED LIGHT, A GREEN TIMING CURCUIT CONTROLLED BY THE ELECTRICAL ENERGY REPRESENTING THE SAMPLED GREEN LIGHT, BLUE TIMING CIRCUIT CONTROLLED BY THE ELECTRICAL ENERGY REPRESENTING THE SAMPLED BLUE LIGHT, EACH TIMING CIRCUIT GENERATING AN OUTPUT SIGNAL WHEN A PREDETERMINED EXPOSURE HAS OCCURED FOR THE COLOR WITH WHICH IT IS ASSOCIATED, A RELAY CONNECTED TO EACH TIMING CIRCUIT AND ENERGIZABLE BY AN OUTPUT SIGNAL FROM THE CIRCUIT WITH WHICH IT IS CONNECTED, EACH RELAY BEING PROVIDED WITH A SET OF NORMALLY OPEN CONTACTS AND FIRST AND SECOND SETS OF NORMALLY CLOSED CONTACTS, A RED FILTER, A GREEN FILTER AND A BLUE FILTER, RESPECTIVE SOLENOIDS FOR INSERTING SAID FILTERS ONE AT A TIME INTO THE PATH OF LIGHT EXTENDING FROM SAID EXPOSURE LAMP TO SAID MATERIAL, THE SOLENOID FOR THE RED FILTER BEING IN SERIES WITH THE FIRST SET OF NORMALLY CLOSED CONTACTS OF THE RELAY CONNECTED TO THE RED TIMING CIRCUIT AND THE NORMALLY OPEN SET OF CONTACTS OF THE RELAY CONNECTED TO THE BLUE TIMING CIRCUIT WHEREBY CLOSURE OF SAID LAST-MENTIONED CONTACTS WILL ENERGIZE THE SOLENOID FOR THE RED FILTER IF SAID RED CIRCUIT RELAY IS DEENERGIZED, THE SOLENOID FOR THE GREEN FILTER BEING IN SERIES WITH THE FIRST SET OF NORMALLY CLOSED CONTACTS OF THE RELAY CONNECTED TO THE GREEN TIMING CIRCUIT AND THE NORMALLY OPEN SET OF CONTACTS OF THE RELAY CONNECTED TO THE RED TIMING CIRCUIT, WHEREBY CLOSURE OF SAID LAST-MENTIONED CONTACTS WILL ENERGIZE THE SOLENOID FOR THE GREEN FILTER IF SAID GREEN CIRCUIT RELAY IS DEENERGIZED, SAID SOLENOID FOR THE BLUE FILTER BEING IN SERIES WITH THE FIRST SET OF NORMALLY CLOSED CONTACTS OF THE RELAY CONNECTED TO THE BLUE TIMING CIRCUIT AND THE NORMALLY OPEN CONTACTS OF THE RELAY CONNECTED TO THE GREEN TIMING CIRCUIT, WHEREBY CLOSURE OF SAID LAST-MENTIONED CONTACTS WILL ENERGIZED THE SOLENOID FOR THE BLUE FILTER IF SAID BLUE CIRCUIT RELAY IS DEENERGIZED AND SAID SECOND SET OF NORMALLY CLOSED CONTACTS ALL BEING PARALLEL SO AS TO DISCONNECT SAID CONTROL MEANS FROM SAID SOURCE OF POWER AFTER ALL OF SAID RELAYS HAVE BEEN ENERGIZED, WHEREBY SAID CONTROL MEANS WILL IN TURN DEENERGIZED AND SHUTTER SOLENOID TO BLOCK FURTHER TRANSMISSION OF LIGHT FROM SAID LAMP SOURCE TO SAID MATERIAL.