New pilot valve idea

High guys!
Now that Eurospudguns is up again, I'd like to introduce a new idea of mine, that I had at work.

You all might know these polyurethane foam guns....



So I thought of the parts that I have and made a rough sketch.
Differently from BtB's design of a high pressure push button valve, this valve is pulled to open.
The fittings would be 1/4". The I.D. of the nipples are 7.5mm (I already drilled one up to 8mm).
I have a 8mm bolt laying around that needs some o-ring grooves and a hole in the middle with a screw to catch the spring.

[/img]

The advantage of this design is the massive flow because the exit hole will be fully open without a bolt in the middle.
It also acts like a check valve if you decide to pressurize into the release hole.

Another idea would be, to make the hole of the left fitting a little bigger, add a little surface and catch the bolt with a trigger.
After the valve piloted, the bolt returns into closed position, forced by the spring.

I thought of the same thing.
The ones we sell have a 1/4" fitting on top!

I would try to make the nose shorter.
It would be perfect in combo with a modded solenoid valve.
That would make a sweet and clean inline launcher.

The problems I had were, I couldn't take a used one because of the foam residue..and a new one was way too expensive.Also the long nose bothered me.
The valve is the same as the one in my pressure washer handle.Also a pull back thingy..

But I'm curious what you'll make of it!

I've already looked out for foam guns on ebay and different shops.
Damn, those are expensive ,especially the good ones with screwable parts.

Anyways, tomorrow I will give it a try. We will see how good it works.

How I said, I took the time today and build the pilot I was thinking of and that's what I came up with.



View of the internal parts.


The o-ring grooves took a little time because I made them on a poor mans lathe (aka drill press ). I had to grind the head of the screw and the nut a little down to fit into the 1/4" tee.


After I hooked it up to the compressor it worked extremely well, without any air leaks. The flow is great and the bolt pulls absolutely the same with or without pressure.

Amazing!!

That's even better than the original foamgun!

With a lever attached to it it could even be hammered!
Very well made too.

Thanks !

But I think I will do some minor changes.
I think that there is not enough space between the bolt and the tee fitting which restricts the flow a little.
I'm going to use a 3/8" or 1/2" tee and some reducing fittings with the same setup to increase flow.

that's quite interesting... I think you could probably even use it as the main valve if you could find something that can open it fast enough... e.g. an air cylinder

you could also plug the exhaust and use a pipe instead of a rod... so that air would flow through the pipe after being released... it would be like QDV but turned inside out

of course the pipe itself could possibly load ammo and close off ammo port as it moves forward...

I think that could be combined with an air cylinder to build a fullauto valve... something that I suggested to use with the QDV

I think I could get it to cycle by using a 3/8" tee, nipple, bolt and stronger spring, sealing a 1/4" hole.

I thought of many things to use it for, including a 20 bar water gun.

with or without an air cylinder ??

you could probably get it to cycle without an air cylinder by using area differential.. so it would be like a homemade pop-off valve..

By area differential.

How I said before. Using a bigger bolt in a 3/8" tee, grinding one side down and add a o-ring to seal a 1/4" hole, et voilà.

I thought of taking the spring out of the tee and make it adjustable to set a certain release point.

yeah I know I just wanted you to clarify that...

a pressure spirng might be a good idea... the design will require some tinkering to find the right pressure...

I wonder what will happend as soon as the valve open... would it open a little bit more or would it shut ?
I think you know that JSR has been experimenting with a similar design... but his was farting instead of cycling