I have been thinking to mount an automatic titrator. The most important parts are the liquid pump and the flow meter. I wanted something cheap and easy to buy. But, it is not a easy task.
Once, I was in a cosmetics shop, not for me, and I saw a Dettol No Touch Hand Wash System for R$ 27,40, here in Brazil. I bought one to umount and remove the liquid pump.
I took some photos the unmount process. This is the link to the PicasaWeb album.
I am really impressed about the quality of the parts and the design of the project. All parts are labeled with the recycle code. The black parts and the external case (white and gray) are ABS and the translucent parts are PP.
The pump is a plunger pump with two valves. When one is open, the other is closed. It works well when it is filled with liquid.
In a next post I will show the pump controlled by a switch to deliver volumes.