OK, I'll be AFK the next couple of days (hiking in and near the Dutch mountains) and maybe my water pump puzzle was too specific, or water pumps are generally considered less sexy compared to ships, cars and planes. The closest guess came from Jim, so I would like to ask him to step in.
Anyway, take a look at this little beauty:
It's a Lambach pump, a special flavor of a hydraulic ram (Impulse pump). It is driven by the works water (from a river with sufficient slope), but not by the current (= kinetic energy) but by the hydrostatic pressure (=potential energy). In case of the pump near Vossenack (A small village in the beautiful Eifel region) the works water was branched off from River Kall 28 meters above the pump.
It was used to transport drinking water from a deep well to a storage tank 180 meters above the pump. More than 208 liters per minute of works water were needed to transport 27.7 liters of drinking water per minute.
The Lambach pump, an outstanding example of hydraulic engineering, was invented in Marienheide near Cologne. Some 100 units were built. They were famous for their low-maintenance and reliability and reached a degree of efficiency of up to 90%.
And this is how it works:
Some remarks:
- In reality both gears are on the same level but the lower one (in the schematic) is not connected to the axle, the small eccentric bolt (the red triangle thingy) is.
- The fast movement of the "hammer" ensures that the inlet/outlet valves (A E E A) for the works water open/close rapidly. Otherwise the pump would come to a halt.
- The four valves in the drinking water piping are simple back-pressure valves.
- The transport pistons (Förder-Kolben) have to be much smaller than the driving pistons (Trieb-Kolben) and this ratio had to be calculated individually for each pump (hydrostatic pressure, transport hight etc.).