Electrical apparatus responsive to particle motion through guard and detecting electric energy fields

Claim 1

ELECTRICAL APPARATUS COMPRISING, MEANS DEFINING A PASSAGE FOR RECEIVING A PARTICLE BEARING FLUID MEDIUM ENTERING AT ONE END OF SAID PASSAGE AND LEASVING AT THE OTHER, SAID MEDIUM AND PARTICLES HAVING DIFFERENT ENERGY FIELD ALTERATION PROPERTIES, FIRST MERANS FOR ESTABLISHING A SUBSTANTIALLY CONSTANT GUARD ENERGY FIELD IN A FIRST REGION OF SAID PASSAGE ADJACENT TO SAID ONE END, SECOND MEANS FOR ESTABLISHING A DETECTING ENERGY FIELD IN A SECOND REGION IN SAID PASSAGE ADJACENT TO SAID FIRST REGION, SAID MEANS FOR ESTABLISHING A DETECTING FIELD HAVING MEANS FOR ESTABLISHING A STATIC COMPONENT SUBSTANTIALLY EQUAL TO SAID GUARD FIELD AND MEANS FOR ESTABLISHING A TRANSIENT COMPONENT WHEN ONE OF SAID PARTICLES CROSSES THE BOUNDARY BETWEEN SAID FIRST AND SECOND REGIONS, AND MEANS RESPONSIVE TO THE OCCURRENCE OF SAID TRANSIENT COMPONENT FOR PROVIDING AN OUTPUT SIGNAL CHARACTERISTIC OF SAID PARTICLES CROSSING SAID BOUNDARY, SAID MEANS RESPONSIVE TO THE OCCURRENCE OF SAID TRANSIENT COMPONENT INCLUDING POLARITY SENSITIVE MEANS FOR PROVIDING AN OUTPUT SIGNAL ONLY WHEN SAID TRANSIENT COMPONENT IS OF A PREDETERMINED POLARITY.