SpudFiles

Hey guys,
like some of you know I'm more into pneumatics but while thinking over some issues about my gun i had the following idea...



The pushbutton is based upon a pneumatic pilot valve and BtB already tested it at very high pressure.

The thread of BtB: http://www.spudfiles.com/forums/i-gotz- ... 18317.html

How it works:
The piston in the fueling chamber has got a little equalization hole so the gas can pass by, while the spring keeps it in place. When the button on the release valve is pushed the piston forces the metered fuel into the chamber. Release the button and the spring pushes the piston back into the first position.


I don't think that i will ever build this but I thought it's a quite elegant way to fuel a combustion.

I'm afraid it's all a bit unclear.

Care to explain further?

It works basically like a pneumatic. When the pushbutton valve is closed the pressure at both sides of the piston are the same.
Push the valve and you provide a negative pressure. The piston is pushed forward by the higher pressure in the butane reservoir (or what what ever you use).

The metered fuel is pushed into the chamber of you combustion.

What keeps the fuel from flowing back through the piston? If the equalization hole is that small, then the amount of time to re-fill the meter volume will be as long or longer than it would take to operate a traditional fuel meter, discounting the advantage.

If you're looking into a one-touch metering design, it's been done before with a three way valve. It can be as simple as a three-way ball valve or as ergonomic as a three-way pushbutton or lever valve.

EDIT: like the type used here.

How I said before, I'm not that much into combustions and didn't really studied all possible ways of fueling.

The fact that these pushbutton valves are a quite new concept in pneumatics made me think that it hasn't been done on a combustion before.

Besides, the time scale between fueling, firing, venting the chamber and reloading should be enough to equalize the pressure in the fueling chamber and set the piston back into "ready" position.

Even if this idea isn't fully sophisticated ... it's something new and maybe there is someone interested in it.

Have a look here. It is the maker of the launcher with the one-touch meter I linked to. It just shows how quickly the meter works in conjunction with the rest of the launcher.

Also, jagerbond has an impressive fuel metering device as well.

How about attaching a Q.E.V. with the meter pipe in the cylinder port, the combustion chamber on the exhaust port, and use this pushbutton valve you've come up with as a pilot for the Q.E.V.? Same operation as the meter you propose, just quicker to reset (although a little overly complicated compared to a three-way).

Again, not riding all over your idea, just saying that there are simpler ways to do the same thing.

There might be easier ways to fuel a launcher but maybe something totaly different develop from this idea.

I just wanted to share some thoughts.

You had your own ideas to this concept already...

Ha ha, I've actually used a Q.E.V. for fuel injection before on a failed piston hybrid. Ergonomic to use, remote controlled, but I wouldn't do it again...

Looks interesting.
I am wondering if the spring could be replaced by the fuel pressure, and where the diagram has "fuel" would be air or oxydizer.
The Push button could maybe somehow be "T"'d to both.(???)
No time to dream it up right now though, I got to go pick up my lady.
She'll probably ask me what I'm thinking about, " are you thinking of another woman...or beer?", "No honey, just machine parts"... 8)

I got to go pick up my lady.
She'll probably ask me what I'm thinking about, " are you thinking of another woman...or beer?", "No honey, just machine parts"... Laughing Cool

lol I know it might sound strange but I acctually had a situation like this


a 3 way valve seems to be a much better idea... just think that you could hook it up to the same switch that acts as a trigger voila you (almost) have a semiauto combustion

POLAND_SPUD wrote:...lol I know it might sound strange but I acctually had a situation like this...

It happens to me all the time...One way to explain it is tell her something like, "The time we most connect is when we Aren't talking..."
Other than that it's, "Sorry honey, just machine parts I might one day make money off" [/romantic spudding]...

I'm back!!! And in a good mood. (TMI 2 reasons)
I just solved the riddle to this design problem I've been thinking of since JSR's Mini hammer valve post (abstract thought)...:

OK, one side has oxydizer (higher pressure), other side has fuel (lower pressure), How do you combine the two without a bulky pressure regulator???:
I THINK I GOT IT TODAY!!! :
Diameter differences in the pipe and piston!(so simple,D*mn I'm stupid)
Any how, one side has fuel with large ID on pipe.
Other side has air/oxydizer with smaller diameter ID same pipe.
The piston in middle has two diameters (stepped).

That way, the pressure applied to the fuel side of piston, would be equal to the pressure on the oxydizer side of piston and the valve "T"'d to both could open and niether would overpower the other.

Just designed a compact propane carberator or a hybrid fueling device with no need for a regulator.
Maybe for personal use I will call it a "ThunderReg." 8) 8) 8)

maybe post a pic of this design as your expelnation doesn't tell me much... (sorry... it might be my fault though.. it's late and I am quite tired)

Hmm interesting food for thought.

Very curious for a diagram of your idea. Trying to picture it, but don't see how a stepped piston would regulate volume or pressure?

I need to settle on a fueling method soon so I can build that component and am having trouble seeing how to fit a regulator let alone two. If there's a more compact way I'm all ears!

daccel wrote:Hmm interesting food for thought.

Very curious for a diagram of your idea. Trying to picture it, but don't see how a stepped piston would regulate volume or pressure?

I need to settle on a fueling method soon so I can build that component and am having trouble seeing how to fit a regulator let alone two. If there's a more compact way I'm all ears!

The two volumes for fuel and for air is a good track. Lose the piston, spring, etc and simply use proportional metering volumes. To get them to the same pressure, a differential pressure guage or pair of matched guages can be used to fill each meter to the same pressure, then combine them and deliver through a single mixed outlet to the chamber.

I toyed with someting earlier so instead of measuring two pressures, only one would be measured and the other would have a tracking regulator and fill the propane meter to the same pressure as the air automaticaly so on delivery, they had the proper proportion and proper volumes. On pressure drop they would both dispense in proper proportion.

I was kicking the idea for fueling a full auto gumball machine gun combustion launcher with a goal of writing my name in plywood with gumballs machine gun style. Due to budget and other obligations, I'm not building it for the contest. I'm working on my primary project instead. Current goal is breaking the sound barrier on less than 200 PSI with solid proof.

POLAND_SPUD wrote:maybe post a pic of this design as your expelnation doesn't tell me much... (sorry... it might be my fault though.. it's late and I am quite tired)

Still working out the design. I think I got overexcited last night, when I tried to draw out what I seemed to visualize so well, it just didn't come together well (Yet).

Here's an explaination of what I came up with:
I was thinking the fuel side would be larger diameter.(imagine one half of the pipe length).
When the fuel enters (through check valve), it presses a piston which has a small diameter rod extruding into (other half of pipe) the smaller diameter of the pipe.
The smaller rod presses a check valve on the air/oxydizer tank and the air/oxydizer enters into the smaller ID/ smaller volume half.
seems like the two would equalize and could somehow(? hose from each side "T"'d to the push button valve OP???) Or be triggered based on piston position.

It's sort of like, imagine the spring from the stick type tyre gauges (the one's that have a spring inside) and made the surface area of the plunger say twice as large, when it read 100psi, you'd actually only have 50 psi, because twice the surface area is pressing on the spring than normally.
(Pretty simple but it got me excited so far) 8)

The idea started when I was looking at JSR's mini-hammer valve, imagining a check valve on each side, and the hammer spring could release the hammer the fuel check valve, The fuel pressure would shot it back at the oxydizer valve, and they both would vent into the firing chamber. It would require fiddling, but heck a lot of good mechanics don't like carb work even.

I was also imagining a cylinder where the fuel enters (through check valve), and presses a piston forward,
as the piston moves forward a port hole is exposed in the cylinder wall and the oxydizer enters through port (w/Check or one-way valve),
Giving it the necessary pressure to press or activate a pilot valve,
to cause the (proper) mixture to dump into the firing chamber.
edit: Or it takes place in the firing chamber and the piston is a BFB, and when the pressure moves it far enough (also loading shot), it switches the spark on.

Had another I haven't woked out, and not sure if it makes sense, where the hose on one side of chamber enters into the other side of chamber as well, pressing a piston center, ...still trying to figure if it's scientifically possible though... 8)

Anyway not to "hijack" It's still on topic due to the valve and similarities IMO So any thoughts on that?