first act volunteering and now starting a home haunt of my own im now starting to use pneumatic cylinders. Im doing this project that uses a cylinder to push something about 90 degrees. Going up is simple enough but how would i make it come down by a hand opperated devise/valve from a different area by the hose?
not sure what you mean... you must be powering it up by air and I'm not sure what you meant by bringing it down.
the air used to extend the cylinder must escape after being extended to allow the gravity to push it down no?
Originally Posted by Dreamreaper
Sounds like youre using a single acting cylinder, meaning air forces it to extend, but the gravity will reset it. You will need a 3 way valve for this type of cylinder. If you use a double acting cylinder, you will need a 4 way valve which allows air to extend and return the rod. Google some basic pneumatics and you will see what Im talking about. Its not all as complicated as people make it out to be.
Hey Biohazard, hopefully this gives you some good insight to how it works.
Here is a Single Acting Cylinder setup.
Your airline connects to the "quick connect" silver colored piece (usually 1/4" dia.).
When the valve get turned on either by motion sensor/pressure mat, or simply plugging it in, it will send air down the single air line for as long as its on. Once the valve gets turned off, it automatically returns the air thru the little exhaust piece, but this is where gravity comes in. It will need to be mounted so that the weight of the prop lowers the cylinder.
And this is a setup for a dual-acting cylinder.
In this case, there is always air flow thru the valve, wether its plugged in or not. Once you connect an air pressure line to the valve via the "quick connect", it will send air down thru the #1 line I have marked.
Once the valve recieves power via a motion sensor/pressure mat, it will reverse airflow from the #1 line and push air thru the #2 line. At the same time, the air that was in the #1 line goes out thru the exhaust.
When power is cut off from the valve it reverses the air flow again, and sends air back into the #1 line, while releasing the air that was just in the #2 line thru the exhaust.
Typically, when the valve is in the off position(and hearing how you want your prop to work), you want the piston itself to be down(or inside the cyliner). If so, then you want to connect your air lines in the opposite order as this diagram shows.
In other words, the way this diagram shows, when the valve is off, the piston is in the out position because air is always in the #1 line. All you have to do is connect your #1 line to the front/top of cylinder rather than at the bottom like this diagram shows.
This is just what i was looking for, thanx and hope you dont mind if i add ya to my buddies list for any future questions i have since it seems you know what your talking about...
Originally Posted by brad