F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
F04B43/00—Machines, pumps, or pumping installations having flexible working members
F04B43/12—Machines, pumps, or pumping installations having flexible working members having peristaltic action
F04B43/1253—Machines, pumps, or pumping installations having flexible working members having peristaltic action by using two or more rollers as squeezing elements, the rollers moving on an arc of a circle during squeezing