Air-tight Single Piece Pump - Shkolnikov Pump

thingiverse

Well, one printed part anyway. You still need to put in some tubing. After having some trouble with the first peristaltic pump I tried, I did some Google-ing and came across this:http://microfluidics.stanford.edu/Publications/Micropumps_Cooling/Shkolnikov-selfpriming-rollerfree-minature-peristaltic-pump.pdf It is basically a diaphragm pump with the check valves and diaphragm integrated into a single piece of plastic. The best performing version so far can be viewed here: http://youtu.be/fRKeDQPz7xw With some more tweaking I'm sure it can be made better. The nice thing about it is that it requires very little plastic, and is very compact. In the paper they drive it with an eccentric cam. Naturally I want to make some computer-controlled colored-water tubing thing with a bunch of these now. Also, real 3d-printed squirt guns. Update: There is currently a problem with this pump that doesn't arise until a few days after assembly. Presumably due to creep, the downstream valve slowly loses its ability to seal completely, resulting in greater backflow and then failure. I will experiment but I may not be able to solve this problem without adding pieces (thinking of a set screw plunger sort of deal). Version History: V2 (11/1/2011): Improved stroke volume and reduced backflow. Instructions (1) Print the part. (2) Thread tubing that is soft enough to be pressed into an airtight seal. I used the following: McMaster Part Number 5236K835 (Disclaimer: Make sure liquid you are pumping is chemically compatible with tubing you use.) (3) Complete circuit of some sort with couplings or whatever. McMaster sells the plastic ones in the video for reasonably cheap.