Hall probe for measuring the intensity of a changing magnetic field in a mass spectrometer

Claim 1

MASS SPECTROMETRIC APPARATUS FOR DETERMINING THE MASS NUMBER FROM THE MAGNETIC FIELD STRENGTH IN THE GAP OF THE SEPARATION MAGNET OF A MASS SPECTROMETER IN WHICH MASS SEPARATION IS EFFECTED BY DEFLECTION IN SAID MAGNETIC FIELD AND THE MASS RANGING BY CONTINUOUS ALTERATION OF SAID MAGNETIC FIELD COMPRISING, SAID MASS SEPARATION MAGNET, MEANS DEFINING A HALL PROBE IN SAID MAGNETIC FIELD, A SOURCE OF AN A-C SIGNAL, MEANS COUPLED TO SAID SOURCE FOR APPLYING AN A-C SIGNAL OF PREDETERMINED AMPLITUDE PROVIDED BY SAID SOURCE TO SAID HALL PROBE TO ESTABLISH A CURRENT THEREIN FOR COACTING WITH SAID MAGNETIC FIELD TO DEVELOP A HALL A-C POTENTIAL REPRESENTATIVE OF SAID MAGNETIC FIELD STRENGTH IN SYNCHRONISM WITH SAID A-C SIGNAL FROM SAID SOURCE, STEPPABLE ATTENUATING MEANS COUPLED TO SAID A-C SIGNAL SOURCE FOR PROVIDING A COMPARISON A-C SIGNAL WITH MAGNITUDE SELECTIVELY CHANGEABLE IN STEPWISE INCREMENTS, MEANS FOR COMPARING SAID COMPARISON SIGNAL WITH SAID HALL A-C POTENTIAL WHICH POTENTIAL IS REPRESENTATIVE OF THE MASS NUMBER THEN DETERMINABLE TO PROVIDE A TRIGGER SIGNAL WHEN THE MAGNITUDES OF SAID COMPARISON A-C SIGNAL AND SAID HALL A-C POTENTIAL BEAR A PREDETERMINED RELATIONSHIP, AND STEPPING MEANS RESPONSIVE TO THE OCCURRENCE OF EACH OF SAID TRIGGER SIGNALS FOR CHANGING THE ATTENUATION IMPARTED BY SAID STEPPABLE ATTENUATING MEANS TO CHANGE SAID COMPARISON SIGNAL BY ONE OF SAID STEPWISE INCREMENTS.