Oval Gear Meters are a member of the Positive displacement flow meter family. They operate by repeatedly filling and emptying compartments of a known volume with a liquid. The flow rate is then calculated based on the number of times these compartments are filled and emptied.
The design of the oval gear flow meter is relatively simple; oval shaped gear-toothed rotors rotate within a chamber of specified geometry. As these rotors turn, they sweep out and trap a very precise volume of fluid between the outer oval shape of the gears and the inner chamber walls with none of the fluid actually passing through the gear teeth