SpudFiles

well this is a pull valve which im currently designing, it works by, well... pulling it!, its bassically a sealed end which you pull apart whith your fingers (a trigger) when its pulled apart air can pass through, on i used silicon gaskets from hose guns and stainless steel pull rod to get it to seal air tight, all im left to do now is build the trigger assembly, air can be added on either side, doesnt matter really, the green is the seals two are stationary and one is attched to the rod, its stops air from passing very well,, then at the back theres a huge spring which keeps everything shut. this valve is meant to be fast opening and fast closing, without the need to for a piston valve, which needs to be pumped extra and isnt quite usefull for something where you have a very limited air supply, also as i said its meant to only release air quickly, and close quickly without exhausting all its supply like a piston valve does.



heres the acutal working model

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New stuff

thats the seal face, the little rod in the second pic seals up against it, ive tried it at 20-30 psi and it seems to work fine, i need to buy a new pump.

Looks interesting, woud be good to see some more pics of the actual thing, and maybe a video. I'm surprised that it stays shut with pressure pushing on the rod.

sorry but it's just a piston valve... but not actuated by pilot vavle but by your hand... it's nothing new

POLAND_SPUD wrote:sorry but it's just a piston valve... but not actuated by pilot vavle but by your hand... it's nothing new

I was pretty damn sure that was it, I thought I was missing something so I didn't post.

I presume it would improve power though, because there would be no pilot volume.

I suppose that you could have this cycle if you had a gear system like you do in an AEG. It would just push and pull the piston creating a pulsed air supply.

You could just attach a trigger to it with a string spring behind the trigger, so that it works semi auto, but like that paintball trigger, I cant remember what its called now, thats has pressure behind the trigger to allow you to pull it rapidly.

acutally troll hammer thats what im planning to do, my trigger will have a ratchet on top of it which will pull back the valve to its full opening, (about 1.5cm back) then the ratchet will go down imediately closing the valve, release trigger and repeat, its air conservation at its best.

whats a string spring tho?

oh ya about this

I'm surprised that it stays shut with pressure pushing on the rod.

well im just currently testing it like this, because none of my parts are glued toghether yet, meaning it would blow up. if i filled it from the non rod part it would blow. also the rod is backed by a pretty big spring and pressure on it would be good, making it oh so easier to open. AAAANNNNNDDDD as i said you could fill it from either side without leaks, but i rather not as it might throw the gasket out of the valve and get it lost in my messy workspace lol. those gaskets were ripped off 2 hose guns. im using this trigger as a semi auto trig for some high powered paintball or airsoft gun. depending on what barrel i use, probably some electrical conduit sleaved in a aluminum pipe from a ski-pole.

POLAND_SPUD wrote:sorry but it's just a piston valve... but not actuated by pilot vavle but by your hand... it's nothing new

acually after doing some research i realise this is a push pull valve, similar to those used in some nerf guns. saw something similar at nerfhaven while browsing, calling it a piston valve is not really "correct" because this doesnt work like one, its not equalising the chamber with a pilot, then dumping the pilot, its simply pressurized and releases air into the barrel.calling this a piston valve would be like calling a butterfly valve a ballvalve, similar but not exactly the same. im surprised no one has adapted this design yet, nerf haven has a tut on something similar, although my valve uses sealing gaskets instead of a chamber sealing piston like this. whatever pretty similar, i guess i havnt invented anything new http://nerfhaven.com/homemade/zero_basicvalve/

and i found thishttp://nerfhaven.com/homemade/zero_semiautovalve/
which is pretty interesting too, although im using a mech system for air management based on how you pull the trigger, itll work better since it doesnt rely on a temp air resevoir, and can be calibrated.

as QuaziGNRLnose its kinda like a "pull valve" and a piston valve combined
nice design and everything but it isnt really that new

newbmatic wrote:as QuaziGNRLnose its kinda like a "pull valve" and a piston valve combined
nice design and everything but it isnt really that new

yes i just posted something along that lines, but its still new to this site from what ive seen

Your guess on what a string spring is, is as good as mine, I meant to write strong

It certainly seems that you have thoroughly researched this, and I think its a very interesting concept, that has potential for a semi auto.

I have thought about doing something like this before when I accidentally pressed my ramrod too far on a piston cannon and it let out a quick burst of air.

yea, this isnt meant to be a (dump valve) meaning its not supposed to have high flow like a piston valve, but it releases air quickly and can close in a snap so its very well suited for semi auto use, or anything where youd wanna be able to fire and close the valve before you exaust your air supply. i made it simply because ball valve piss me off with their low flow, and slow opening. this valve only needs to move back 1 cm or a bit more to release its air and the heavy spring closes it even faster than you can open it, if it were any bigger like a normal piston valve it would be useless for a semi auto application

i suggest anyone whos contemplating building a piston valve for some semi auto type use should contemplate using this method or the semi auto method shown on nerf haven, which can handle higher flows due to its temp air resevoir, meaning it wont waste your air tank in one shot. its especially usefull if u want a revolver type large barrel patatoe gun.

no sorry but it is a piston vavle... a piston valve can be acctuated using pilot valve or you can move the piston using your muscles or electric motor... whatever...

the fact that someone has called something does not mean that it is a push pull valve or whatever... it just means that some guy from some site has called it like that...



I can call my sister 'JSR'.. but she is still my sister not JSR... (thx god)