Thread: Pneumatic speed
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Unread 10-01-2014, 12:50
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Re: Pneumatic speed

Quote:
Originally Posted by Jibri Wright View Post
Actually the piston is receiving 60psi the instant the solenoid switches. The reason it shoots slower in normal function is because the air on the other side of the cylinder has to be pushed out by the new air coming in. It takes time to do this and force. If you stall the piston's extension in the manner you're talking about then this allows for the air on the other side of the cylinder to be released. Pressure does build up on the other side, but all the air technically doesn't go into the piston. After the shaft is released does the remaining air enter the cylinder.
no, the cylinder receives only 'flow' from a 60 psi reservior. the pressure in the cylinder will only be what is required to move the piston forward until the piston becomes either obstructed or fully extended. This pressure may be as low as one psi delta.

What I'm saying is that if you just hold the piston in place for a short bit, the pressure will be able to build up. The business about the air getting out of the back side of the cylinder is so not-important. If you build-up 60 psi on one side and have effectively zero on the other side, it will move very fast. Our prototype can shoot across the room. But accuracy and repeatibility are still in question.