mass_flow_differential_gear_box

grabcad

This is another entry for the Grundfos Challenge 2019, featuring a hydraulic gearbox with theoretically zero backlash. The concept behind this gear is straightforward: two gear pumps are used, where pump one has a mass flow rate 1/1500 times greater than the second pump at the same RPM in a closed circuit. As a result, they are constrained to have the same mass flow, meaning gear pump two will turn 1500 times slower than pump one. Both gears in the pumps are subjected to the same pressure, but the gear area exposed to this pressure is much larger on the second gear, similar to a car jack. A CFD simulation would be an excellent way to validate the theory, but unfortunately, my current hardware does not have the necessary power for such calculations.