On 29 April 2010 16:05, yann jautard <[email protected]> wrote: >> A rotary valve (either a plug valve or a ball valve) should counteract >> this problem. >> http://en.wikipedia.org/wiki/Ball_valve
> You're rigth, but not easy to drive with a pneumatic cylinder. I have seen rotary pneumatic actuators. > I'm thinking in making something like a 2-2 spool valve, with one end of > the sheath connected to the output, so when the drawer goes back to > close the flow, it acts like a piston to produce the suction required to > cleanly shut off the flow. I did a search earlier for "constant volume valve" and found this product (very clear drawing on page 5) which looks very much like what you are describing. http://www.vindum.com/Vindum%20Valve%20Manual0306.pdf -- atp ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
