Pneumatic Valve Question?

[homefab13]

Hi, My name is Jesse and I am new to the forum. I am not an engineer by trade just a metal fabricator. I am hoping you guys could give me some advice on a project I am working on. I am looking for a pneumatic valve similar to the attached picture that has a spring return for the valve. Basically when I push the button in it will inflate an object and when I let go it will return to a neutral position where it will stop inflating and when I pull the button it will force air out the other valve and when I let go it will return to a neutral position. I have bought springs and cut them to a proper length to get the valves to work in this fashion but from a quality and safety stand point I will not be able to use my, "homemade valves" in the real world. Any advice were to purchase valves that work in that manner would be greatly appreciated. Thanks in Advance!

 

[homefab13]

For some reason the html tag for pic did not work so here is a link to the picture
free screen capture

 

[zdas04]

You are describing the function of a 3-way valve with one of the inlets connected to source and the other to vent. Generally three-way valves have a lever instead of a push-pull switch because the pull-to-vent function is ergonomically awkward.

David Simpson, PE
MuleShoe Engineering

"Belief" is the acceptance of an hypotheses in the absence of data.
"Prejudice" is having an opinion not supported by the preponderance of the data.
"Knowledge" is only found through the accumulation and analysis of data.
The plural of anecdote is not "data"

 

[gerhardl]

Hi!

The one you are searching for is a 5/3 manual valve with spring return. See symbol and example of one supplier (several wellknown exists worldwide) .

http://catalog.airtec-usa.com/browser?&plpver=10&prodid=1007&itemid=1159&assetid=1595

Explanation of symbol: 5/3 : five ports, three operating positions. Mid square shows neutral position and all ports(1 to 5) blocked, left square shows flow when lever (lever symbol far left) pushed left. Returns to mid position by spring when lever is not held (far left spring symbol, no hatched symbol showing detent). When lever is pushed right: flow as shown in far right square, with spring return as shown by far right spring symbol.

Contact supplier and discuss necessary flow at given pressures. Flow /cv not to be mixed with port size capacity, real flow opening may differ.

If you can accept two levers (one in, one out) two pieces 2/2 way with spring return might be cheaper.

Good luck!