Electrical device for measuring the rate of an occurrence of an event

Claim 1

IN COMBINATION, MEANS FOR PRODUCING A TRAIN OF VOLTAGE PULSES THE FREQUENCY OF WHICH IS VARIABLE OVER A PREDETERMINED RANGE, METER MEANS CONNECTED TO RECEIVE THE PULSE TRAIN AND TO PRODUCE A RESULTANT MAGNETIC FIELD THE ANGULAR DISPLACEMENT OF WHICH IS RELATED TO THE FREQUENCY OF THE PULSE TRAIN, THE METER MEANS COMPRISING FIRST AND SECOND PARALLEL CONNECTED COIL MEANS FOR PRODUCING FIRST AND SECOND MAGNETIC FIELDS ALONG FIRST AND SECOND AXES RESPECTIVELY, MEANS FOR PRODUCING A THIRD MAGNETIC FIELD ALONG A THIRD MAGNETIC AXIS AND HAVING A SUBSTANTIALLY CONSTANT MAGNITUDE, THE FIRST AND SECOND COIL MEANS BEING DISPOSED SUCH THAT THE THIRD MAGNETIC FIELD IS OPPOSING THE FIRST MAGNETIC FIELD AND THE SECOND MAGNETIC AXIS INTERSECTS THE FIRST AXIS AT A PREDETERMINED ANGLE, CAPACITOR MEANS CONNECTED IN SERIES CIRCUIT WITH THE PULSE PRODUCING MEANS AND THE PARALLEL-CONNECTED COIL MEANS THEREBY TO VARY THE MAGNITUDES OF THE FIRST AND SECOND MAGNETIC FIELDS IN THE SAME SENSE AS A FUNCTION OF THE FREQUENCY OF THE PULSE TRAIN, AND ROTATABLY SUPPORTED ARMATURE MEANS RESPONSIVE TO THE MAGNETIC FIELDS TO BE ALIGNED WITH THE RESULTANT THEREOF.