Apparatus for sensing and controlling fluid flow in the form of discrete free-falling drops

Claim 1

IN APPARATUS FOR SENSING AND CONTROLLING THE DROP RATE OF A FLUID MATERIAL, THE COMBINATION COMPRISING MEANS DEFINING A FLUID FLOW CHANNEL HAVING A VERTICALLY DISPOSED CHAMBER SECTION, MEANS FOR VARIABLY RESTRICTING THE FLOW OF FLUID IN SAID FLOW CHANNEL TO PRODUCE FREEFALLING DROPS IN SAID CHAMBER SECTION, SENSING MEANS ASSOCIATED WITH SAID CHAMBER SECTION FOR PRODUCING ELECTRICAL PULSES AT A RATE DIRECTLY PROPORTIONAL TO THE DROP RATE IN SAID SECTION, CIRCUIT MEANS COUPLED TO THE SENSING MEANS FOR PRODUCING AN OUTPUT VOLTAGE WHICH VARIES IN ACCORDANCE WITH THE RATE OF RECEIPT OF THE ELECTRICAL PULSES, AND ELECTROMAGNETIC MEANS RESPONSIVE TO SAID OUTPUT VOLTAGE AND OPERATIVELY CONNECTED TO SAID FLOW RESTRICTOR MEANS FOR CORRECTIVELY VARYING THE SETTING THEREOF FOR MAINTENANCE OF A PREDETERMINED DROP RATE.