Fluid metering device with conduit flushing by-pass

Claim 1

A LIQUID MEASURING DEVICE COMPRISING A CYLINDER, A PISTON SLIDABLE IN SAID CYLINDER DIVIDING IT INTO A MEASURING CHAMBER AND A PRESSURE CHAMBER, MEANS BIASING SAID PISTON TO A NORMAL POSITION TO ENLARGE SAID MEASURING CHAMBER AND REDUCE THE PRESSURE CHAMBER, A CHECK VALVE CONTROLLED INLET LINE TO SAID MEASURING CHAMBER ADAPTED TO BE CONNECTED TO A SUPPLY OF LIQUID TO BE DISPENSED IN MEASURED QUANTITIES FROM SAID MEASURING CHAMBER, A CHECK VALVE CONTROLLED OUTLET LINE FROM SAID MEASURING CHAMBER, A VALVE CONTROLLED INLET LINE TO SAID PRESSURE CHAMBER ADAPTED TO BE CONNECTED TO A WATER LINE UNDER PRESSURE, A BY PASS FOR SAID CYLINDER HAVING AN INLET IN THE WALL OF SAID CYLINDER IN A POSITION LOCATED IN THE MEASUREING CVHAMBER IN THE NORMAL POSITION OF THE PISTON BUT IN THE PRESSURE CHAMBER WHEN THE PISTON IS NEAR THE END OF ITS STROKE TO DIMINISH THE VOLUME OF THE MEASURING CHAMBER AND AN OUTLET ALWAYS IN SAID MEASURING CHAMBER, SAID BY PASS CONSTITUTING AN OUTLET FROM SAID PRESSURE CHAMBER THROUGH SAID MEASURING CHAMBER, AND A BLEEDER LINE CONNECTING THE PRESSURE CHAMBER WITH THE OUTLET LINE FROM SAID MEASURING CHAMBER DOWNSTREAM OF THE CHECK VALVE THEREIN.