They patented Archimedes Screw Pump? That almost feels like impossible.,(reply>), It's not an archimedean screw pump for 2 reasons - 1. the auger is stationary - this is straightforward enough, but mainly 2. the screw does not need to be a close fit in the surround - this is a crucial difference and improves manufacturability and maintainability.,(reply>), A <i>reverse</i> Archimedes screw pump. The only reason it seems impossible is that Archimedes should have thought of it.<br>...Okay, maybe not Archimedes; it wouldn't be much use while muscle-power was basically the only source of power around. But da Vinci or a contemporary, maybe?,(reply>), It's inverse Archimedes Screw Pump. Rotating the housing instead of the screw. That's why, maybe? 🤔