| 摘要 |
1,127,083. Magnetometers. FORD MOTOR CO. Feb.15, 1967 [March 9, 1966], No.7155/67. Heading G1N. A magnetometer using superconducting material operates on the principle that, in a known magnetic field, the superconductivity of the material is destroyed when current flowing through the material is increased to a known value. The magnetometer comprises two semicylindrical members 11, 12, Fig.2 of superconducting material, e.g. vanadium, joined together by insulating separators 13, through which screws 15, 16 of superconducting material, e.g. niobium, are screwed to provide a weak electrically conducting link between the two members. The value of the current at which the superconductivity of the weak link is destroyed can be regulated by adjustment of the screws. A variable A.C. or D.C. current, Fig. 3 (not shown), is applied to the two members and a galvanometer (G) or oscilloscope is connected across one of the screws. In a modification several weak links could be held enclosing a plurality of superconducting elements. In use the current is increased until a voltage is first detected by the galvanometer or oscilloscope at which point the value of the current flowing through the members is indicative of the intensity of the magnetic field in which the magnetometer is situated, for a particular adjustment of the screw. The whole apparatus is maintained at a temperature of about 40‹K at which vanadium and niobium are normally superconducting.
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