Apparatus for determining electrical properties of metal, such as its resistivity and utilizing measurements made at high and at low temperatures

Claim 1

APPARATUS COMPRISING A POWER SUPPLY, FIRST CIRCUIT CONNECTED TO SAID POWER SUPPLY, MEANS TO ACTUATE SAID FIRST CIRCUIT THEREBY GENERATING A MAGNETIC FIELD IN SAID FIRST CIRCUIT WITH RESULTING FLUX PENETRATION OF A METAL MEMBER ADAPTED TO BE POSITIONED WITHIN A MAGNETIC FIELD AND ADAPTED TO BE TESTED, A SECOND CIRCUIT POSITIONED WITHIN THE MAGNETIC FIELD GENERATED BY SAID FIRST CIRCUIT THEREBY RECEIVING AN INDUCED VOLTAGE FROM THE METAL MEMBER ADAPTED TO BE POSITIONED WITHIN SAID MAGNETIC FIELD AND MAGNETICALLY COUPLED WITH SAID METAL MEMBER, MEANS TO REDUCED THE TEMPERATURE OF SAID FIRST AND SECOND CIRCUITS TO A TEMPERATURE SUBSTANTIALLY BELOW 273* K., MEANS TO ACTUATE SAID SECOND CIRCUIT; ONE SET OF DEFLECTION PLATES TO A RECORDER CONNECTED TO SAID SECOND CIRCUIT; A FIRST VARIABLE RESISTANCE DEVICE CONNECTED TO SAID POWER SUPPLY, A VARIABLE ENERGY STORAGE DEVICE ADPATED TO BE CONNECTED ACROSS SAID RESISTANCE DEVICE, A SECOND VARIABLE RESISTANCE DEVICE CALIBRATED IN TERMS OF THE ELECTRICAL PROPERTIES OF SAID METAL MEMBER AND ADAPTED TO BE CONNECTED TO SAID ENERGY STORAGE DEVICE, ACTUATION MEANS ALTERNATELY CONNECTING SAID ENERGY STORAGE DEVICE TO SAID FIRST VARIABLE RESISTANCE DEVICE AND TO SAID SECOND VARIABLE RESISTANCE DEVICE TO ALTERNATELY CHARGE AND DISCHARGE SAID ENERGY STORAGE DEVICE, SAID LAST MEANS COUPLED WITH SAID MEANS TO ACTUATE SAID FIRST CIRCUIT, A THIRD CIRCUIT CONNECTING THE OTHER SET OF DEFLECTION PLATES OF SAID RECORDER TO SAID SECOND RESISTANCE DEVICE, MEANS TO ACTUATE SAID THIRD CIRCUIT; A DELAY CIRCUIT COUPLED TO SAID SECOND CIRCUIT ACTUATION MEANS AND SAID THIRD CIRCUIT ACTUATION MEANS, AND MEANS TO ACTUATE SAID DELAY CIRCUIT, SAID LAST MEANS COUPLED TO SAID FIRST CIRCUIT ACTUATION MEANS AND TO SAID ENERGY STORAGE DEVICE ACTUATION MEANS.