Positive displacement flowmeter

Claim 1

A POSITIVE DISPLACEMENT FLOWMETER FOR MEASURING THE FLOW RATE OF A FLOWING FLUID COMPRISING: (A) CONDUIT MEANS MOUNTED IN A SUBSTANTIALLY VERTICAL POSITION, SAID CONDUIT MEANS HAVING A PASSAGEWAY OF A KNOWN VOLUME FORMED THROUGH AT LEAST A PORTION THEREOF; (B) TUBULAR INLET MEANS CONNECTED AT ONE END TO THE LOWER END OF SAID CONDUIT MEANS; (1) THE FREE END OF SAID INLET MEANS BEING LOCATED AT A LEVEL ABOVE SAID LOWER END OF SAID CONDUIT MEANS; (2) SAID FREE END BEING ADAPTED TO BE CONNECTED TO THE SOURCE OF SAID FLOWING FLUID; (C) RESERVOIR MEANS FOR RECEIVING AND HOLDING A MEASURING FLUID HAVING A HIGH SURFACE TENSION; (D) DISPENSER MEANS CONNECTED BETWEEN THE OUTLET OF SAID RESERVOIR MEANS AND SAID TUBULAR INLET MEANS FOR RELEASING WHEN ACTUATED A PRECISELY MEASURED QUANTITY OF SAID MEASURING FLUID INTO SAID INLET MEANS SO THAT SAID RELEASED FLUID FORMS A LIQUID SLUG WHICH SEALS SAID CONDUIT MEANS THUS RESULTING IN SAID SLUG BEING MOVED THROUGH SAID PASSAGEWAY IN A GIVEN TIME BY SAID FLOWING FLUID THEREBY GIVING AN INDICATION OF THE FLOW RATE OF SAID FLOWING FLUID; (E) RETURN MEANS OPERATIVELY CONNECTED BETWEEN THE UPPER END OF SAID CONDUIT MEANS AND SAID RESERVOIR MEANS FOR AUTOMATICALLY RETURNING SAID LIQUID SLUG TO SAID RESERVOIR AFTER SAID SLUG HAS PASSED THROUGH SAID PASSAGEWAY; (1) SAID RETURN MEANS COMPRISING A TUBE OPERATIVELY CONNECTED AT ONE END TO THE UPPER END OF SAID CONDUIT MEANS AND AT THE OTHER END TO SAID RESERVOIR MEANS; (F) SAID RESERVOIR MEANS BEING LOCATED AT A LOWER LEVEL THAN THE UPPER END OF SAID CONDUIT WHEREBY SAID LIQUID SLUG FLOWS THROUGH SAID TUBE UNDER THE INFLUENCE OF GRAVITY; (G) SAID OTHER END OF SAID TUBE PROJECTING BELOW THE SURFACE OF SAID MEASURING FLUID IN SAID RESERVOIR MEANS THEREBY PREVENTING ESCAPEMENT OF ANY OF SAID FLOWING FLUID THROUGH SAID TUBE.