I would like suggestions on the best way to design a pnuematic circuit for a 3 -position cylinder. The cylinder is made by TRD/Bimba. Has 4 ports - 2 for each piston.
The cylinder is installed vertically with the weight of the tooling (Vacuum Puller)pulling down. In this application with a 2-position cylinder, I plumb the cylinder to Un-dumped air so it remains up when the machine is stopped. Now I need to use a 3-position cylinder in order to place a support under the tooling to support the product before transfer.
Operation would be - full retract on shutdown and startup, Cycle - Cylinder goes full down to retrieve the product and returns to the full up position, once up the support goes under the product and then the cylinder moves to Mid-Position and a transfer will transfer the product. Once the product is transfered and the support is retracted the cylinder would go full down from the mid-position and repeat the cycle.
Hope this isn't confusing!
Last time I did this it worked but not as well as I wanted. I used 3 Valves and a regulator. See Attachment
UO - Un-Dumped Air/Oiled, DO - Dumped Air/Oiled