Increasing the speed and thoroughness and economy of ultrasonic and other non-destructive testing of materials for detecting flaws or variances therein

Claim 1

IN APPARATUS FOR ULTRASONICALLY TESTING AN ELONGATED SPECIMEN FOR THE PRESENCE OF FLAWS THEREIN, THE COMBINATION OF A PLURALITY OF ULTRASONIC SEARCH UNITS PERIPHERALLY DISPOSED ABOUT THE EXTERNAL SURFACE OF SAID SPECIMEN IN SPACED RELATION ONE TO ANOTHER, EACH OF SAID SEARCH UNITS CAPABLE OF BOTH TRANSMITTING AND RECEIVING ULTRASONIC VIBRATIONS, MEANS FOR MOVING SAID SPECIMEN LENGTHWISE PAST SAID SEARCH UNITS, AN ULTRASONIC FLAW DETECTION INSTRUMENT INCLUDING AN ULTRASONIC GENERATOR AND AN ULTRASONIC RECEIVER AND MEANS TO ALTERNATELY CONNECT SAID GENERATOR AND SAID RECEIVER WITH SAID SEARCH UNTIS, SEQUENCE SWITCHING MEANS INTERPOSED BETWEEN SAID INSTRUMENT AND SAID PLURALITY OF SEARCH UNITS, SAID SWITCHING MEANS ADAPTED TO CONNECT SAID INSTRUMENT WITH EACH OF SAID SEARCH UNITS ONE AT A TIME IN SEQUENTIAL AND CYCLICALLY REPEATING ORDER WHEREBY SAID INSTRUMENT TRANSMITS TO AND RECEIVES FROM ONLY ONE OF SAID SEARCH UNITS AT A TIME BUT DOES SO FOR EACH OF SAID SEARCH UNITS.