Pneumatic Claw Question

VEX V5 General Discussion General Forum
#1

Hi guys,
This is a question for those of you who have a pneumatic claw actuated by 2 double acting cylinders with 2 air tanks:
About how many times are you able to open and close the claw before you run out of air. I have heard that a cylinder can be actuated about 20 times before running low, but this doesn’t sound very reasonable for a full length match.

I also have another generic pneumatics question:
Are the double acting cylinders just as powerful in both directions? From YouTube videos that I’ve seen it seems like they retract slower than they extend.

Thanks!

#2

Back when we used double acting pneumatics, we only got about 15 opens and closes. I can’t really see you getting more than 20.

#3

I’m using two tanks with two double acting pistons and I get about 30 - 40 pumps. Going through a full match is never a problem for me. Just remember to use the dial thingy to control the amount of air that goes through.

#4

You will not have the same force in both directions with a double acting cylinder. When calculating extension force you have the piston area * PSI and with retraction force you have (piston area - rod area) * PSI.

#5

From my knowledge of pneumatics the way you have the pressure set changes the amount of times you can use it significantly. Obviously the more times you get out of it the lower the pressure will have to be. Also I have noticed that with the double action it leaks tons of air when it is held extending out which is why we like to use the spring retractable one, this one tends to not lose mass amounts of air like the other.

#6

Ah that’s what I thought, thanks.

Has anyone else experienced this? That doesn’t seem like something that should happen, maybe yours is defective?

#7

As the piston moves out the solenoid expels the air inside the piston as it has to go somewhere.
If your piston is leaking then you should try to find the leak. It could be a problem with your tubing

#8