After successful testing of my prototype pneumatic pinch valve with a 3/8″ bore, I proceeded to design an improved version with a full 1/2″ bore. This version uses silicone tubing instead of latex, which I believe will not contribute any off-flavours, and will not break down eventually as latex tubing is prone to do. In addition, it also has pipe-thread connections for inlet and outlet so it can be plumbed into a system easily, but can be removed if necessary.
See my page here on how it was constructed.
O found your entry from a Google search. I was wondering how the fatigue life is holding up for this valve? I think I can modify this design for animatronics applications. Thanks for the postings! Regards, Peter Crisp, Surrey, BC.
I haven’t actually built the system around that valve design yet.
The silicone tubing I used is just a fairly generic one. I just figured it would last longer than latex tubing from Home Depot, which will grow brittle just sitting there.
If long life is desired, I expect you might do well with the special tubings designed for peristaltic pumps. They’re extremely resilient, designed specifically for this kind of constant flexing.