Quote:
Originally Posted by Cody Burd
hi we are team 3607 asnd we have no idea of how to set up the pnematic system can anyone help
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The standard pneumatic system contains two main parts, a high pressure side and low pressure side. The high pressure side of a pneumatic system contains:
-a compressor (you can do without it, but we'll get to that later)
-automatic relief valve
-pressure switch
-pressure gauge
-accumulators
-vent valve
The compressor is what builds pressure in the system by forcing air into the accumulators (air storage tanks), without letting air escape. The automatic relief valve is used to automatically release pressure once it builds to a certain point (for FIRST competition it must be calibrated to 125psi, which can be done simply with a wrench). You must include a pressure switch to shut the compressor off once the pressure on the high pressure side of the pneumatic system reaches 120 psi. The pressure gauge is self explanitory and the vent valve is used to vent all pressure outside of the system. These are all connected to each other using brass fittings and in order to ensure a good seal, and prevent air leaks, you should wrap teflon tape around all of the threads. Start two threads down from the beginning of the threads and wrap twice around the bolt. Also make sure that you wrap counter clockwise (looking from the bolt head with the end facing away from you) this is so that when you tighten the bolt you tighten the teflon tape instead of unraveling it.
Next you need to step the pressure down from 120 psi to 60 psi (or lower) you do this with a regulator. When you connect the regulator that the high pressure side is connected to the port at the tail end of the arrow (you should see an engraved arrow on the bottom of the regulator). Connect the low pressure side to the port at the head of the arrow and the remaining port should be connected to a pressure gauge to denote the pressure on the low pressure side. To change the pressure of the regulator charge up the accumulators and then pull back the lock ring on the regulator and turn the dial until the pressure is where you want it.
From here you can start adding solenoids. Solenoids are the devices you use to actuate pistons, there are two types (used in FIRST). First is single acting solenoids which switch a cylinder between two positions depending on a low or high voltage signal. When you take away the signal they will switch back to one setting (these are usually the Festo valves provided by FIRST). Single acting solenoids are usually 4 ported one port is for pressure, one for exhaust, and the other ports are connected two either end of the cylinder, or rotary actuator. Double acting solenoids are pretty much the same except the lock into position once they are switched and they have 5 ports, an extra for another exhaust port (these are usually the SMC solenoids that FIRST provides).
That's pretty much all I feel like typing now, but hey I was bored. I should have just told you to look at the pneumatics manuals, search "pneumatics" in the papers section of chiefdelphi media, and look up pneumatics in usfirst workshops section.
So go do that...now