The design is based on that ubiquitous Gear Bearing test print that you often see displayed at 3D printing shows, but a maker and blogger has converted it into a functional peristaltic pump that can be used for any sort of build where you need to precisely move liquid from one place to another automatically.
(…weiter auf 3dprintingindustry.com)
3D Printed Peristaltic Pump
This is a simple peristaltic pump design that is 3D-printed in a single piece, with captive rollers and no rotary wearing surfaces. The only non-printed part, and assembly required, is to add a piece of surgical tubing. This sort of pump is ideal for dispensing known amounts of fluids, or where corrosion or contamination is a problem (e.g. medical applications), for slurries or viscous materials, or where significant elevation gains are required. You can see more information at http://tim.cexx.org/?p=1282