Creating no pressure with double solenoid?

[Combat Chuck]

Hey. I was wondering if it's possible to have no air coming out of the double solenoid during competition. Right now we have it where the solenoid will act both ways, but until we pulse the solenoids, the pistons are retracting, which causes stress on our frame. Is there a way to have it where both of the solenoids can be off at the same time? Thanks.

[greencactus3]

Originally Posted by Combat Chuck

Hey. I was wondering if it's possible to have no air coming out of the double solenoid during competition. Right now we have it where the solenoid will act both ways, but until we pulse the solenoids, the pistons are retracting, which causes stress on our frame. Is there a way to have it where both of the solenoids can be off at the same time? Thanks.

one way is to use another solenoid inline before the solenoid you are using now.
ex) use a single before your double and plug the B and have a tube go from A to the double solenoid. have the tank connect to P.
so when there is no signal to the single, air will not go to the double resulting in no movement in your cylinders.

or,

use the configuration of being able to stop your cylinders at any point..
by just connecting a 3 way splitter to both exhausts of your double, and connecting another tube from that splitter to the P of another single solenoid. plug the B of the single and leave A open.
that way, you can stop the exhaust of your double by controlling the single. stopping exhaust of the double=no movement in your cylinders.

if you didn't understand or have any questions, i'll be happy to answer!
just pm or Email me.

[Jeffrafa]

there is a much easier way....

you can simply use a three-position valve, it works just like a dual solenoid (and looks almost identical), but when you aren't sending electricity to either of the solenoids then it springs to center. This engages "all ports blocked" which basically means no air can flow through the valve at all

we are using two of these on ours, the only thing is you can't pulse power unless you have it give power just long enough for the cylinder to extend.

the advantage is that if you loose air pressure in you're entire system, then that device will still stay wherever you had it assuming it was in the center-off position. the only problem with this is that it takes air to actuate the solenoid (since the solenoid is like a mini-cylinder) so until you regain pressure on the incoming line you will not be able to release the cylinder from the position it was in.

[Jeffrafa]

Since it sounds like you are trying to not send pressure you could also use a three position valve that is "all ports open" in center position.

This means that it works just like the dual except if you don't send a signal to one of the solenoids then it will open up both cylinder ports to exhaust, therefore releasing all pressure in the cylinder and allowing it to freely move.

[ngreen]

Originally Posted by Combat Chuck

Hey. I was wondering if it's possible to have no air coming out of the double solenoid during competition. Right now we have it where the solenoid will act both ways, but until we pulse the solenoids, the pistons are retracting, which causes stress on our frame. Is there a way to have it where both of the solenoids can be off at the same time? Thanks.

Do you mean that you want to stop the cyclinder at a certain position and not have it fully retract and extend?

If that is it check here: http://www.chiefdelphi.com/forums/sh...ighlight=multi

[Biff]

Originally Posted by Jeffrafa

there is a much easier way....

you can simply use a three-position valve, it works just like a dual solenoid (and looks almost identical), but when you aren't sending electricity to either of the solenoids then it springs to center. This engages "all ports blocked" which basically means no air can flow through the valve at all

we are using two of these on ours, the only thing is you can't pulse power unless you have it give power just long enough for the cylinder to extend.

the advantage is that if you loose air pressure in you're entire system, then that device will still stay wherever you had it assuming it was in the center-off position. the only problem with this is that it takes air to actuate the solenoid (since the solenoid is like a mini-cylinder) so until you regain pressure on the incoming line you will not be able to release the cylinder from the position it was in.

Where did you get these valves? It's to late for us to get them this year... but this would be a big help in the future.
Thanks Tom Cooper

[Jeffrafa]

Most any Pneumatics distributer would have them.


Norgren, SMC, Festo, and Parker all make and carry three position solenoid valves.

[greencactus3]

WHAT!!!!?!???
we were allowed to use 3 position ones!?!?!?!
i never knew that!! oh, well... if only i knew... would have saved about 2lbs...
(our double solenoids are about 1.5lbs each. oh, so if any one has any spare lighter ones, we'd really appreciate it if you can exchange them for our heavy ones even just for the 3 days.