Vacuum Valve

[Ben Piecuch]

I hate to burst your bubble here guys, but those "Direct Acting Valves" are not legal for 2007 FIRST robots. <R46>, as well as this question in the Q&A pretty much cover the use of non-air operated solenoid valves.

A non-air operated solenoid valve uses an electronic solenoid, which is considered to be a motor in the eyes of the GDC. What Keith has suggested is to make your own non-air operated solenoid valve using kit parts/motors. His solution of adapting a servo to rotate a manual shut-off valve is the perfect solution to this problem. Other motors could be used (globe, window) but they would also require a spike, limit switches, etc... The servo trumps all of that in terms of weight and simplicity.

We had a hard time dissecting the rules to determine which solenoid valves were legal and which were not. Through a few online searches, we were unable to find low-cost, low-weight, pressure rated air-operated solenoid valves. More than likely, we'll be using the servo solution.

BEN

[Mike Betts]

Originally Posted by Ben Piecuch

I hate to burst your bubble here guys, but those "Direct Acting Valves" are not legal for 2007 FIRST robots. <R46>, as well as this question in the Q&A pretty much cover the use of non-air operated solenoid valves...

Ben,

My interpretation of <R46> is somewhat different than yours. I believe that the intent of the rule is to prevent electro-mechanical actuators. An example is the solenoid in an old fashioned door bell.

I would argue that "pneumatic solenoid valves" come in two flavors, air-piloted and direct acting, both of which would be legal.

This would be legal while this would not.

JMHO.

Mike

P.S.: Someone should post this to the FIRST Q&A to get a definitive answer.

[Andrew Blair]

I did. Kinda.

Direct Acting Valve?


01-18-2007, 03:00 PM
FRC306 vbmenu_register("postmenu_3519", true);
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Direct Acting Valve in Vacuum?
We have a direct acting solenoid valve rated for 100 psi that we wish to use expressly in our vacuum loop.Though not rated for 125 psi, it is more than adequate for the vacuum it will be operating in. Is it acceptable to use?

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01-19-2007, 09:52 AM
GDC vbmenu_register("postmenu_3656", true);
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Re: Direct Acting Valve in Vacuum?
No. Under Rule <R105>, all "off the shelf" pneumatic devices must be rated for at least 125 psi. There is no exception for devices that are used for vacuum applications.


What this implies is that any off the shelf pneumatic solenoid valve (meaning used to control the flow of air in a mechanical system, not provide mechanical actuation directly), may be used so long as it is rated to 125 psi. A direct acting valve serves the same role as a piloted valve, just with more power draw.

Too bad we can't use the one we have laying around though...

[lilbowser]

Did any one ever find one that would be alowed becuse we could realy use one.