electronic piston valves

[us sniper]

has anyone on this site ever tried to build a homemade piston valve that was triggered electronically. I just looked at how solenoids are triggered and it seems pretty easy with an bumper hooked up to an electromagnet. This is what I am thinking, but I think the electronics could be improved to increase the charge delivered to the electromagnet.

http://s153.photobucket.com/albums/s240 ... t=new1.jpg

[pizlo]

Why, pneumatic actuation is faster?

[us sniper]

I like the trigger system where is is mor realistic and hopefully this way it could look more like the commercial guns. I also want this to work because I am trying to build something that looks like either the daystate rifle that JSR has or the new daystate hunter.

[MaxuS the 2nd]

I don't really see any improvement over pneumatic actuation of the piston valve. The electromagnetic would have to be fairly strong in order to pull back a piston faster than it can be piloted normally. It's like reinventing the wheel. But go for it anyway and tell us how it worked out.

[judgment_arms]

Sorry friend, it’s not going to work to as you drew it; the air will just push the piston back.
You’re going to have to use the electromagnet to hold the piston shut; in which case, if the electromagnet failed the gun would go off prematurely, possibly resulting in damage to person, place, or thing.

No, I think the answer to your problem is the use of a sear mechanism to hold the piston shut, it would be much more reliable, more compact, and wouldn’t require a battery.
That’s my two cents ($0.02u.s.).

[clide]

I haven't seen an electromagnetic valve on a homemade gun, but there is a pneumatic pitching machine (Zooka I believe) that uses an electromagnetic valve. I've posted a link to the patent somewhere on this site, but I'm too lazy to look it up right now, you can probably find it by searching if you are interested.

[jackssmirkingrevenge]

I am trying to build something that looks like either the daystate rifle that JSR has or the new daystate hunter.

Have a look here - the Daystate works just like most PCPs, using a hammer valve, but instead of a spring loaded hammer there's a capacitor which discharges through a solenoid which strikes the valve, allowing enough air to escape to fire one shot.

[Hotwired]

It would be nice to have a simple electronic trigger that didn't care less about pressures but the only practical things we've known of are solenoid triggered diaphragm valves which tend to have a rather moderate pressure rating.

Of course if you're not planning on going above say 150-200psi they can be used to trigger a piston valve quite well and with a very light button trigger instead of a fairly large and/or stiff blowgun lever.

[bugsingelyn]

Has anybody ever used a solenoid to push (or pull?) the piston back? It seems simple, but I don't know how powerful solenoid's can get, and how much battery it would use.
I thought of this a while back, and had a solenoid from a sprinkler valve, but they aren't strong enough I don't think. I am now on a constant search for a stronger one.

[THUNDERLORD]

I saw a really cheaply made electric staple gun at home depot(like 40$ now). It probably uses a spring and some kind of solenoid.It would be easy to take apart. It got me thinking about attaching a piston like a spring piston type air gun has to the part that normally drives the staple.

[jackssmirkingrevenge]

It got me thinking about attaching a piston like a spring piston type air gun has to the part that normally drives the staple.

You'd get performance similar to an AEG, it's not really worth the bother.

Has anybody ever used a solenoid to push (or pull?) the piston back?

It's possible theoretically, but in practice even with small calibres the force required is considerable (for example with a 6mm barrel at 100 psi, you'd need almost 4.5 lbs of force to pop the piston open) and would require a substantial solenoid and battery setup.